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Restore hair and scalp equilibrium for holistic beauty!

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments


For years, hair care products have been focused on addressing damage by providing solutions to repair, prevent and maintain hair health. With increased awareness, consumers now recognize that healthy scalp is also a fundamental foundation for healthy hair. Holistic care means to restore the hair at its core while maintaining a healthy scalp. With personalization and self-care at the forefront, consumers are looking for solutions that are inspired from skin care with an emphasis on natural and clean ingredients. In this article, we will discuss factors that affect scalp and hair health and provide an overview of the innovative technologies including specialized product treatments that help restore hair and scalp equilibrium.

Stressors that impact hair and scalp equilibrium

Hair and scalp are affected by several factors such as UV exposure, pollution, humidity, mechanical, chemical, physical stressors, and occlusion such as hats and head protectors (like wigs, protective styles etc.) [1]. Sebum on the scalp diffuses along the hair shaft and can attract product build-up and dust from air which can affect the scalp’s overall health. Additionally, the bacterial and yeast proliferation on the scalp is commonly associated with enhanced desquamation, itching, scratching and redness [1]. Some hair products may leave deposits on the scalp, while others can strip hair’s natural oils to the point that it begins to over-produce sebum [2].

Oxidative stress, i.e., free radicals from sources like UV and pollution, can weaken scalp skin health and cause aging [3]. Sensitive scalp syndrome has been reported to arise from increasing levels of air pollution. Symptoms of sensitive scalp include itching, prickling in the scalp, dandruff, oily scalp, and pain in the hair roots. Pollutants also can migrate into the dermis and through the hair follicle (HF), leading to oxidative stress and hair fall [3]. Hormonal changes, medical conditions, heredity, and aging are cited as common causes of hair fall, but there has been a lot of searches for hair loss associated after COVID-19 (+250%) and how to stop hair fall post COVID increased by a whopping 1,250% [4].

The skin surface and follicular openings are recognized sites of rich microbial colonization and intense immune citation, with crosstalk across the skin barrier [5]. A disrupted microbiome may cause infections and inflammation to the scalp [6]. This disruption may aggravate scalp disorders that can lead to acne, eczema, alopecia, scalp psoriasis, seborrheic dermatitis/dandruff, etc. The aforementioned diseases of the skin and the hair follicles [HFs] are all due to the dysfunction of dysbiosis – the imbalance of the skin microbiome [5]. Scalp conditions also impact the quality of hair causing the resultant cuticular cells to be less flexible than normal, which may impair both anchorage and subsequent fiber surface integrity due to an oxidative stress environment [7]. Hair fibers become more brittle and chip off. This results in a rougher cuticle that is also less functionally effective [7].

Cleansing of hair and scalp is also vital. How often you should cleanse your hair is determined based on your overall scalp health and can be attributed to hair texture. Some cleansers can be harsh and overly stripping, removing all natural oils, which disturbs the bacterial environment and can lead to irritation, redness, and flaking [8], while others may have a high oil load that can have a detrimental effect on oily scalp.

As scalp and hair go hand-in-hand, there is also tremendous focus on the damage hair sustains from the environment, washing, bleaching, coloring, and the use of different styling regiments. Hair damage affects all types of cross-linking bonds, including disulfide bonds, and can negatively affect the overall structure and ordering of hair lipids and CMC lipids [9]. Bleaching and coloring leads to dry, brittle-feeling hair and fiber breakage. Repeated washing results in lifted cuticles, while heat damage from drying, straightening, or curling leads to a loss of moisture, frizzy hair, and split ends [10].

Market drivers and trends

Over the past five years, scalp-focused searches have increased by 270% which is tied to the fact that one in two people suffer from a scalp issue [11]. Reportlinker projects the global hair and scalp care market will reach $121.4 billion by 2027 and will grow at an estimated 6.5% CAGR over the next five years [12]. Based on the latest data, Spate recommends that brands offer hair and scalp solutions that support skin barrier repair, moisturization and conditioning of damaged locks [12]. There has also been a rise in complex hair and scalp routines among millennials [4]. Need for different scalp products has increased globally, which aligns with consumers’ desire for benefits that address their individual scalp and hair needs. Consumers are also demanding transparency from brands and want to learn more about the ingredients used in their products and their mechanism of action. They also place a growing emphasis on the use of natural, organic, and clean alternative ingredients.

Advances in technology targeting hair and scalp concerns.

There have been many advancements in technology that provide holistic solutions to help protect, prevent, and restore hair and scalp equilibrium.

Sebum Control:

An ingredient that leverages a novel encapsulation technology*, ensures targeted delivery and controlled release of actives onto the scalp and hair to deliver instant sebum reduction [12]. This ingredient allows consumers to leave more time between washes, leading to water conservation [12]. A naturally occurring amino acid (INCI: Glycerin (and) Water (and) Sarcosine) effectively aids in the reduction of an oily scalp. It helps to reduce flakes on the scalp and assists in rebalancing the microbiome. Additionally, this ingredient also helps fight against stress, pollution, and product build-up [2]. Another ingredient, based on lamellar body-inspired delivery system (INCI: Aqua, Lecithin, Niacinamide, Lysolecithin, Phenethyl Alcohol, Caprylhydroxamic Acid, Tocopheryl Acetate, Caprylyl Glycol, Phytic Acid), has been designed to target hair follicles where it delivers actives to regulate sebum and the microbiome [6].

Oxidative Stress:

Antioxidants are very well known and can be added to any kind of hair product due to their water-based molecular structure. They help to prevent the formation of oxidative stress and provide a wide range of benefits to both hair and scalp. A blend of three natural and powerful antioxidants, an extract of a medicinal plant forms a non-occlusive shield against urban pollution and protects hair and scalp against environmental stress [13]. A fermented extract of organically grown yerba mate leaves (INCI: water (aqua) (and) glycerin (and) Ilex paraguariensis leaf extract) is designed to help protect hair from oxidative stress-induced damage and help maintain healthy hair roots for optimal growth after only one shampoo treatment [12]. Brands like Keep It Anchored (P&G owned) are developing formulas that are powered by a combination of antioxidant salts that relieve oxidative stress, a zinc compound to improve scalp condition and B vitamins known for skin barrier health [8].


* INCI: Aqua (and) Cetyl Palmitate (and) Cucurbita pepo seed extract (and) Disodium EDTA (and) Ethylhexylglycerin (and) Helianthus annuus seed oil (and) Lauryl Glucoside (and) Melaleuca alternifolia leaf oil (and) Phenoxyethanol (and) Rosmarinus officinalis leaf extract (and) Sorbitan Stearate (and) Tocopheryl Acetate



With zinc pyrithiones (ZPT’s) ban in Europe in cosmetic applications, formulators are now scouting for new active ingredients. A biomarine ingredient derived via biotechnology (INCI: Water (aqua) (and) Pseudoalteromonas Ferment Extract (and) Sodium Salicylate) has been shown to reduce sebum, itchiness, and flakes on the scalp, while also preventing their recurrence in both rinse-off and leave-on applications [4]. An algae oil (INCI: Triolein), containing more than 90% of the beneficial omega-9 helps hydrate, rejuvenate, and repair the scalp. It also nourishes hair follicles and protects against hair fiber lipid degradation upon UV exposure [4]. In addition, another ingredient positioned as an emollient with antimicrobial properties (INCI: decylene glycol), helps protect the skin from scalp to toe. Among other functions, this ingredient supports dandruff control concepts. It also provides a China-compliant alternative to the antidandruff active zinc pyrithione [12].

Hair Loss:

Broccoli and pumpkin seed seem like unexpected choices for formulators developing anti-hair loss products. Sulforaphane, which is an isothiocyanate isolated from broccoli, increased the expression of an enzyme in the liver that accelerated DHT degradation and consequently inhibited hair loss, as shown in an animal model [14]. Clinical efficacy of pumpkin seed oil (PSO) versus 5% minoxidil foam in subjects with female pattern hair loss (FPHL)after three months of treatment showed the pumpkin oil significantly decreased hair shaft diversity and the number of vellus hairs with results comparable to the minoxidil foam [14]. Another ingredient, a protein and peptide combination (INCI: Keratin (and) Hydrolyzed Keratin (and) Oxidized Keratin (and) Water) stimulates skin cells to proliferate by up to 160% faster than a placebo while simultaneously stimulating human keratinocyte migration and the expression of collagens IV and VII, thus improving the anchoring of follicles. The ingredient’s anti-inflammatory agent reduced the PGE2 response in cells undergoing inflammatory stress by up to 70%, reducing scalp inflammation, itching and premature hair follicle death [15].

Balancing the Biome:

Inhibition of the growth of harmful bacteria can lead to a better balance in oil secretion; this can be achieved using a unique probiotic fermentation technology rich in amino acids, polysaccharides, protein, and other biologically active substances [16]. A natural prebiotic (INCI: Inulin) can also help rebalance the skin’s microbiota and offer skin hydration that outperforms hyaluronic acid. The prebiotic is based on inulin extracted from chicory root and agave and works by selectively supporting protective organisms to help restore the microbiota layer [6]. Since 2020, We have witnessed a burgeoning of scalp products with Cannabidiol (CBD) boasting microbiome benefits [5] and recently we also have seen use of Cannabigerol (CBG) that helps to rebalance the scalp microbiome and promotes hair growth. Lastly, an ingredient (INCI: Lactobacillus Ferment Lysate) that utilizes the properties of prebiotic oligosaccharides as an approach to postbiotic bacteriocin procurement can deliver scalp moisturization and redness reduction [4].

Protecting hair, beyond the scalp,

Hair, after it rises from the scalp surface, also goes through damage from consumers’ grooming practices and external stimuli. Cleansing, conditioning, and strengthening solutions have been extensively discussed in the past. Currently, the use of bond builders is trending and growing in hair care. They are promoted as being able to penetrate into the hair to improve or restore the internal structure, giving rise to an improvement in mechanical properties [9]. According to this definition, bond builders include a broad range of actives, including organic acids, proteins, and lipids [9]. Brands are employing patented peptide technologies and amino acid complexes in multiple product formats that can help prevent and protect hair from the inside-out against all forms of damage.

What’s new and what’s next.

Ingestible hair care products, such as Nutrafol are gaining popularity for promoting hair and scalp health which has helped fuel further ingredient innovation. The introduction of Keranat in food supplements for hair (soft gels, capsules, beauty drinks/shots and cosmetics is said to offer a natural, vegan solution to effectively fight against hair loss while restoring beauty and brightness [12]. The design of neurocosmetic ingredients that modulate neuronal response to improve scalp care and hair quality could be a promising approach for the development of new hair and scalp care routines [17].

Finally, brands like L’Oréal are fostering partnerships with health tech companies to better understand the biological, clinical, and environmental factors that contribute to skin and hair health over time. This comprehensive understanding contributes to the development of a more precise and inclusive skincare approach that cater to the diverse needs of individuals worldwide [18].


The beauty and personal care industry has made great advancements in understanding the role of microbiome that impacts scalp and hair health. New research and findings help steer brands and ingredient suppliers to develop natural, organic, and sustainable solutions that will be a key focus area for future innovation. Furthermore, ingredients inspired by skin care, traditional ingredients, and biotech will continue to drive the growth of the hair and scalp care category.  It is imperative that brands continue their efforts in developing inclusive and personalized solutions to address consumers specific scalp and hair care needs. Finally, educating consumers on choosing the right products and regime that address their specific needs is crucial, in addition to providing guidance on how to use the products effectively to achieve the desired benefit.


  1. Luigi Rigano, Ph.D., Rigano Laboratories S.r.l., Milan, Italy, “Hair and Scalp Care Go Hand-in-Hand,” Global Cosmetic Industry, 2016
  2. BASF Corporation, “Rebalance the scalp microbiome with Scalposine,” Cosmetics & Toiletries (March 2020)
  3. D. Roddick-Lanzilotta, Ph.D., R.J. Kelly, Ph.D., and P.R. Sapsford, “Keratin Blend Anchors Follicles and Prevents Pollution-induced Hair Fall,” Cosmetics & Toiletries (September 2019)
  4. Ashlee Cannady, Aprinnova Juliana Gomiero, Stephanie Neplaz, Raphaelle Tron, “Hair and Scalp Cleansing and Care Skinification, ZPT Ban, Fermentation and Damage Repair Self-care,” Cosmetics & Toiletries (June 2022)
  5. Sharleen Surin-Lord, Dermatologist, “The ‘Skinification’ of Hair Care” Happi (June 2021)
  6. Laura Lam-Phaure, “Formulating on Trend: Skinification of Hair,” Cosmetics & Toiletries (June 2022)
  7. “Effect of Scalp Health on Hair Growth,” MedEsthetics (December,2021)
  8. Christine Esposito, “Natural Ingredients in Shampoos & Conditioners Benefit Scalp & Hair” Happi (December ,2021)
  9. Paul Cornwell, Ph.D., TRI Princeton, Princeton, NJ; and Jennifer Marsh, Ph.D., Procter & Gamble, “How Bond Builders ‘Repair’ Hair,” Cosmetics & Toiletries (February 2023)
  10. Rachel Grabenhofer, “Patent Pick: Binding Agreement for Hair Repair,” Global Cosmetic Industry (October 2019)
  11. Julia Wray, “Why applicators are the secret ingredients for scalp care,” Cosmetic Business (April 2023)
  12. Lisa Doyle, “Hair & Scalp Care: Targeted and Premiumized,” Global Cosmetic Industry (September 2022)
  13. Rahn Ag, “Radicare®-Eco: The Urban Antidote for Hair and Scalp,” Cosmetics & Toiletries (April 2022)
  14. Mohamed l. Elsaie, Lee Reuveni, Stephanie Neplaz, Sebastien Massard, “Restoring and Reviving Hair: Scalp Health, Laser Treatments, Natural/Sustainable and Deep Repair,” Cosmetics & Toiletries (February 2022)
  15. Michele Behrens, “FK Scalp from Keraplast Prevents Hair and Scalp Health Pollution,” Cosmetics & Toiletries (February 2020)
  16. Peter Smedley, “Bloomage Highlights Hair Shield, Scalp Care and Fermented Anti-aging at SCC76”, Cosmetics & Toiletries (December 2022)
  17. Maria Jose Lopez-Gonzalez, Nuria García and Isabel Devesa, AntalGenics S.L., Elche, Spain, “Neuro-cosmetic Targets for Scalp and Hair Care,” Cosmetics & Toiletries (June 2022)
  18. Julia Wray, “L’Oréal embarks on world’s ‘largest and most diverse’ skin and hair study”, Cosmetic Business (July 2023)




The Use of Natural Oils to Treat the Skin

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments

The Use of Natural Oils to Treat the Skin

Roger L. McMullen

Fairleigh Dickinson University and Ashland Inc.


The term natural oil refers to a fixed (nonvolatile) oil of animal or plant origin. These types of oils—in contrast to essential (volatile) oils, which are obtained by steam distillation methods of plant matter—are typically obtained from plant seeds and nuts by a mechanical pressing technique or solvent extraction. Natural oils have been used to treat the skin for millennia. For example, evidence suggests that the ancient Egyptians used almond (Prunus amygdalus), balanos (Balanos aegyptiaca), castor (Ricinus communis), moringa (Moringa oleifera), olive (Olea europea), and sesame oil (Sesamum indicum) in cosmetic preparations (1). The natural movement in cosmetics of the twenty first century has led to renewed interest in formulating skin care products with botanical ingredients. In this article, I highlight the use of natural oils in skin care and their benefits for skin health.


Benefits of Natural Oil Treatment

Natural oils nourish, smoothen, sooth, and clean the skin. Skin nourishment is provided by biologically active ingredients in natural oils such as antioxidants and essential fatty acids (2). As an example, the antioxidant activity and health benefits of grape seed oil (Vitis vinifera) mostly stems from the presence of tocopherol, linolenic acid, resveratrol, quercetin, procyanidins, carotenoids, and phytosterols in the oil (3). Essential fatty acids, obtained through the diet or applied topically, are important for maintaining skin health (essential fatty acid deficiently leads to dermatitis) and preventing trans-epidermal water loss (4, 5).


Dry skin is typically rough due to ineffective desquamation. Plant oils can smoothen the surface of skin by providing a lubrication effect and by helping the skin maintain a healthy level of hydration through fortification of the skin barrier. Natural oils can also have a soothing effect on the skin. Anti-inflammatory compounds in the oils can help to reduce skin redness and irritation. Studies have shown that olive, sunflower seed (Helianthus annuus), coconut (Cocos nucifera), safflower seed (Carthamus tinctorius), argan (Argania spinosa), soybean (Glycine max), sesame, jojoba (Simmondsia chinensis), and oat (Avena sativa) oil provide an anti-inflammatory effect in skin (6).


Natural oil-based cleaners are used to remove sebum and makeup from the skin. While conventional surfactants can be very efficacious at cleaning the skin, they can also disrupt the barrier function of skin and remove lipid components important for barrier integrity. A good example of a natural oil-based cleaner was provided by researchers at Mae Fah Luang University in Thailand who demonstrated the effectiveness of tea seed oil (Camellia sinensis) at removing foundation and eyeliner (7).


Composition of Natural Oils

The chief components of natural oils are triglycerides. They usually represent greater than 95% of the composition of natural oils. Triglycerides are formed by the esterification of free fatty acids to glycerol resulting in a molecule with a polar headgroup and three hydrophobic tails (see Figure 1). Triglycerides are synthesized by animals and plants as energy reserves and contain various proportions of saturated, polyunsaturated, and monounsaturated fatty acids. In animals, the fatty acid constituents of triglycerides have greater levels of saturated fats (relative to polyunsaturated and monounsaturated fats), whereas in plants there are greater amounts of polyunsaturated and monounsaturated fats. For this reason, most plant oils are in the liquid state at room temperature.

Figure 1: Molecular structure of a triglyceride. In this example, that fatty acid moieties of the triglyceride contain three distinct entities. The three fatty acid chains in triglycerides can be the same or they can be a mixture. Starting from top to bottom, this triglyceride is composed of palmitic acid (16:0), oleic acid (18:1), and alpha-linolenic acid (18:3).


The fatty acid components of triglycerides can vary in chain length—they can be short (≤ 6 carbons), medium (≤ 12 carbons), or long (12 – 22 carbons)—which effects their physicochemical behavior. In some cases, triglycerides may contain omega-3, omega-6, and omega-9 essential fatty acids. The overall composition of the triglycerides (the types of fatty acids, their length, and the degree of saturation/unsaturation) is unique for each natural oil. For example, coconut oil has higher levels of saturated fats than most plant oils, which is why it exists in the solid state at room temperature.


Natural Oils in Wound Healing

Wound healing consists of the regeneration and tissue repair processes after the development of a chronic (pathological condition) or acute (trauma) lesion in the skin. There are three principal stages in wound healing, which include the inflammatory, proliferative, and remodeling stage. Essentially, these stages are characterized by a series of biochemical and cellular events that involve cytokines, growth factors, and other important bioactive molecules that eventually lead to fibroblast proliferation, collagen synthesis, and epithelialization.


In recent years, it has been established that bioactive fatty acids play an important role in the inflammatory stage of wound healing (8, 9). Essential polyunsaturated fatty acids and their metabolic products are believed to play an integral role in modulating wound healing. Omega-3 (e.g., alpha-linolenic acid) and omega-6 (e.g., linoleic acid) fatty acids metabolize to a number of different molecules including leukotrienes, lipoxins, prostaglandins, and thromboxanes—twenty-carbon chain length bioactive compounds known as eicosanoids (10). In addition to alpha-linolenic acid and linoleic acid, omega-9 fatty acids (oleic acid and erucic acid) were also reported to provide positive anti-inflammatory effects during wound healing (11). In summary, anti-inflammatory and wound healing properties have been demonstrated for various botanical oils including olive oil, grape seed oil, coconut oil, argan oil, jojoba oil, and numerous other oils (6, 12-15).


Natural Oils and Diseases of the Skin

A brief survey of the scientific literature reveals a number of studies investigating the effects of oils on various diseases encountered in dermatology (16). In addition to fatty acids and other lipids in the oils, there are numerous biologically important molecules such as monoterpenes, sesquiterpenes, diterpines (e.g., cannabinoids, tocopherols), triterpenoids (e.g., squalene, sterols), carotenoids, and polyphenols (17). These phytochemicals have been shown to efficaciously alleviate the symptoms of inflammatory skin diseases, such as contact dermatitis, atopic dermatitis, and psoriasis. In addition, dietary supplementation with essential fatty acids has shown beneficial effects in the treatment of acne, atopic dermatitis, pruritis, psoriasis, and skin ulcers (18-20).  Furthermore, supplementation with an omega-3 fatty acid was shown to reduce the risk of skin cancer in organ transplant recipients (patients who undergo transplant procedures have a very high risk of developing skin cancer) (21). There has also been considerable interest in utilizing natural oils produced by the plant Cannabis sativa for the treatment of skin inflammatory diseases. Hemp seed and cannabidiol (CBD) oil have been found to be the most efficacious oils from Cannabis sativa for treating skin inflammatory conditions (22).


Therapeutic Benefits of Natural Oils

One of the principal benefits of treating skin with natural oils is to alleviate dry skin by enhancing its barrier function. Due to compositional differences, each natural oil interacts uniquely with the skin. Some of the most commonly used oils for skin therapy are almond, argan, coconut, evening primrose (Oenothera biennis), jojoba, oat, and olive oil (23, 24). It is noteworthy that while olive oil has a number of reported benefits for skin—mostly for treatment of skin aging, pruritis, and xerosis—there are concerns that it negatively affects skin barrier function (25). Regardless, natural oils help form a physical barrier on the skin surface and function as a source of lipids to fortify the skin’s barrier. Future research could help identify specific oils that should be used for a particular skin treatment modality (26).


Aroma massage therapy consists of the use of essential oils in conjunction with massage techniques. Natural oils are used as carrier oils for the essential oils. In addition to diluting the essential oil, the carrier oil lubricates the skin surface facilitating the massage procedure. Some common carrier oils are almond, coconut, grapeseed, jojoba, and sunflower oil. In general, carrier oils should have a pleasant scent and be aesthetically pleasing when applied to the skin. When choosing a carrier oil, it is best to find an oil that is absorbed well by the skin that does not result in an oleaginous (greasy) sensation.


Neonatal Skin Care

Newborn infants are especially prone to developing dry skin conditions as their skin adapts to life outside of the uterus. From a physiological perspective, infant skin is quite different from adult skin. In infant skin the stratum corneum and epidermis are thinner and there is significant risk of trans-epidermal water loss due to less barrier lipids and natural moisturizing factor. In addition, there is an accelerated breakdown of corneodesmosomes due to the higher surface pH (which affects desquamation) (27). Several studies highlight the possible benefits of treating neonatal skin with botanical oils, such as sunflower, coconut, almond, olive, palm (Elaeis guineensis), and mustard oil (Brassica juncea); however, there seems to be a consensus that further study is warranted to determine efficacy and any proposed mechanisms (28-30). For example, researchers at the University of Sheffield in the UK found that treatment of neonatal skin with olive oil compromised skin barrier integrity and induced mild erythema in patients (31). Furthermore, researchers at Columbia University in New York City reported that olive oil can exacerbate atopic dermatitis and xerosis in pediatric subjects (32).


The Paradoxical Behavior of Natural Oils in Relation to Epidermal Barrier Function

The stratum corneum of skin contains corneocyte cells embedded in a matrix of endogenous lipids consisting of long-chain ceramides, cholesterol, and free fatty acids, organized into multilamellar structures. Sebum is found on the surface of the skin and contains a mixture of triglycerides, wax esters, free fatty acids, squalene, and cholesterol esters. One would expect that treatment of skin with natural oils could help maintain the moisture levels of skin by enhancing its epidermal barrier function via the formation of an occlusive lipid layer on the surface thereby preventing trans-epidermal water loss. However, in recent years it has been discovered that some natural oils may disrupt the skin’s structural lipids thereby compromising stratum corneum barrier function.


Treatment with some oils can fluidize stratum corneum lipids and compromise epidermal barrier function. In fact, natural oils have been used as penetration enhancers in the transdermal delivery of active pharmaceutical ingredients (33, 34). More than likely, the triglycerides in oils that are applied to the skin will be hydrolyzed by resident lipases resulting in the formation of free fatty acids, which can disrupt the ordered structure of lipid lamellae in the stratum corneum (35). In general, the paradoxical effect produced by some oils is thought to be more prevalent in patients suffering from atopic dermatitis and other skin conditions.


Concluding Remarks

Natural lipids are employed in several applications in skin care. In this article, we introduce some of the traditional treatment modalities and highlight some of the most recent studies published in the scientific literature which find health benefits to the skin. The available data suggest an important role for natural oils in treating skin inflammatory disorders, wound healing, skin therapy, and neonatal skin care. Despite the widespread use of natural oils in cosmetic formulations, there is considerable need to conduct further research in this area to better elucidate the mechanisms responsible for the efficacious nature of the oils. Looking ahead to the future, such action will require us to proactively investigate the bioactivity of the components of a broad range of natural oils in a systematic manner. In addition, a better understanding of the detrimental effects of certain oils to epidermal barrier function in specific types of skin needs to be elucidated in future studies.



The author expresses his sincere gratitude to Drs. Gopinathan Menon and David J. Moore for revising the text and offering useful suggestions.



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  29. Pupala S, Rao S, Strunk T, Patole S. Topical application of coconut oil to the skin of preterm infants: a systematic review. Eur J Pediatr. 2019;178(9):1317-24.
  30. Chiabi A, Kenmogne M, Nguefack S, Obadeyi B, Mah E, Meka F, et al. The empiric use of palm kernel oil in neonatal skin care: justifiable or not? Chin J Integr Med. 2011;17(12):950-4.
  31. Danby S, AlEnezi T, Sultan A, Lavender T, Chittock J, Brown K, et al. Effect of olive and sunflower seed oil on the adult skin barrier: implications for neonatal skin care. Pediatr Dermatol. 2013;30(1):42-50.
  32. Karagounis T, Gittler J, Rotemberg V, Morel K. Use of “natural” oils for moisturization: review of olive, coconut, and sunflower seed oil. Pediatr Dermatol. 2019;36(1):9-15.
  33. Viljoen J, Cowley A, du Preez J, Gerber M, du Plessis J. Penetration enhancing effects of selected natural oils utilized in topical dosage forms. Drug Dev Ind Pharm. 2015;41(12):2045-54.
  34. van Zyl L, du Preez J, Gerber M, du Plessis J, Viljoen J. Essential fatty acids as transdermal penetration enhancers. J Pharm Sci. 2016;105(1):188-93.
  35. Leung D, Elias P, Nadeau K, Berdyshev E. Olive oil is for eating and not skin moisturization. J Allergy Clin Immunol. 2021;148(2):652.







Biodegradability considerations for cosmetic ingredients

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments

The topic of “biodegradability” has become extremely important over recent years, but still may not be fully understood. The following is a basic overview for formulators and anyone wishing to know more about this critical issue. (Note that regulations, definitions, and practical guidelines on biodegradability are continually changing, and the comments in this blog are intended to offer general insights, not legal definitions or advice.)

Simply put, biodegradation is the breakdown of organic matter by microorganisms, such as bacteria and fungi[1], and once broken down, the byproducts are carbon dioxide and water vapor. “Bio” is the key prefix here; the difference between “degradable” and “biodegradable” is that while “degradable” products can be broken down by chemical or biological processes, “biodegradable” materials can only be broken down by biological processes.

The concern for biodegradable products began with the issue of microplastics, first detected in the 1970s in the ocean as plastic residue, but not termed “microplastics” until the mid-2000s. (A good and comprehensive article on this by Napper and Thompson was published online in 2020[2].) Many multinational companies have stopped using microplastics (microbeads) in their formulations and other brands are following, but let’s clearly define what are, and are NOT, microplastics! To qualify as a microplastic, four criteria must be met:

  1. It must be a polymer
  2. It must be solid (at RT)
  3. It must be in particulate form
  4. It must be under 5mm in size

All four criteria must be met – if even a single one of these four is not present, the substance is NOT considered a microplastic. And to complicate matters further, there are many exclusions even if these four criteria are met, including the following:

  1. The material is natural
  2. The material is degradable
  3. Its solubility is > 2 g/liter
  4. No carbon atoms in its chemical structure
  5. Its release to the environment is prevented when used
  6. Its physical properties are permanently modified during end use
  7. It is permanently incorporated into a solid matrix during end use
  8. And likely more…

Just because your products may be “natural” does not mean they are “biodegradable” – measurement is key! As mentioned by Dr. Martin Perry, Advanced Development Safety Laboratories, at SCS Formulate in 2021: “Although natural content is good to know, and there is a perception that natural ingredients are more biodegradable than synthetic ones, knowing the biodegradability is important. The natural content of your product or your organic content is not going to be sufficient for you to substantiate anything on biodegradability.”[3]

To be precise, most companies adhere to the standard of “readily biodegradable”, defined as the ability of a product to biodegrade quickly and completely (≥ 60% by OECD 301A-F/ASTM D7373 testing) within 28 days. You might also hear the term “inherently biodegradable,” defined as between 20% and 60% biodegradability as measured by OECD 301A-F testing, but “readily biodegradable” is stricter and preferable.

From the OECD iLibrary: “The OECD Guidelines for the Testing of Chemicals is a collection of about 150 of the most relevant internationally agreed testing methods used by government, industry and independent laboratories to identify and characterize potential hazards of chemicals. They are a set of tools for professionals, used primarily in regulatory safety testing and subsequent chemical and chemical product notification, chemical registration and in chemical evaluation. They can also be used for the selection and ranking of candidate chemicals during the development of new chemicals and products and in toxicology research. This group of tests covers environmental fate and behaviour. In 2017, the section 3 “Degradation and Accumulation” was renamed to “Environmental fate and behaviour” to take into account Test Guidelines measuring endpoints such as dispersion, aggregation.”[4]

As a final note, microplastics and biodegradability concerns are part of a larger issue of minimizing environmental pollution. Some may equate this trend with the apparent discovery of reef damage caused by certain organic sun filters, specifically octinoxate and oxybenzone. There are bans in place on octinoxate and oxybenzone in many countries, including the US (Hawaii, Florida, US Virgin Islands), Aruba, Bonaire (off the coast of Venezuela), Palau and parts of Mexico. However, this is not a biodegradability issue as much as it is a toxicity issue, and the science is still unclear as to the actual effect of residual organic sunscreens on coral reefs.


[1] Focht DD. “Biodegradation”. AccessScience. doi:10.1036/1097-8542.422025.

[2] Napper & Thompson, “Plastic Debris in the Marine Environment: History and Future Challenges”. Global Challenges. doi: 10.1002/gch2.201900081.

[3] https://www.cosmeticsdesign.com/Article/2021/11/18/Biodegradable-beauty-focus-needed-in-natural-and-organics-before-regulatory-change-says-expert#

[4] https://www.oecd-ilibrary.org/environment/test-no-301-ready-biodegradability_9789264070349-en


Ben Blinder is the Executive Director, Business Operations at Gattefossé USA, with P/L responsibility for the personal care and pharmaceutical business units in the US and Mexico. He is also a founding member of the Advisory Committee on Diversity & Inclusion for Gattefossé in North America. Ben holds a BS in chemical engineering from Lehigh University.

Sunscreen formulations – emphasis on inorganic sunscreens

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments

Ever since the FDA published their proposed monograph ruling in February 2019 recognizing titanium dioxide and zinc oxide as the only Category I (Safe and Effective) sunscreens, a cascade of reformulations of most sunscreens products on the US market took place.  Inorganic sunscreen formulations are now center-stage and are slowly replacing organic sunscreen formulations.  In fact, the trend started in 2018 when the state of Hawaii proposed a ban on Octinoxate and Oxybenzone stating that these two sunscreens have a negative effect on coral reefs.  Now that the ban is in effect, another bill is proposing to ban sunscreens containing Octocrylene and Avobenzone for the same reasons.  It is true that many regulatory bodies including the FDA did not support the Hawaiian ban, and the Personal Care Product Council (PCPC) is addressing the proposed monograph rulings. All these actions might lead to uncertain outcomes.  In fact, in a few years the US consumers might be limited to the use of products containing inorganic sunscreens only (with the exception of Ensulizole and Ecamsule).  There is some hope that certain Time and Extent (T&E) molecules are being reviewed by the FDA and may be approved for launch.  Bemotrizinol is a front-runner and its use in formulation is quite good as it protects both in the UVB and UVA areas.

Selecting the right inorganic sunscreen

Zinc oxide and titanium dioxide not only refract light but also absorb it.  The refractive index of titanium dioxide is 2.8 whereas that of zinc oxide is only 2.0.  This makes titanium dioxide much more effective at scattering light in a formulation.  From and absorption point of view, zinc oxide and titanium dioxide have conductance bands around 3.4 and 3.1 eV, respectively.  This makes zinc oxide a bit more efficient in protecting against UVA rays and titanium dioxide more efficient at shielding UVB rays.  As particle size decreases you get much more pronounced blue shift due to a change in the band-gap width.  For example, a 0.15 eV blue shift has been reported for 4.7 nm titanium dioxide compared to bulk.

Keep in mind, when particles become smaller than their optimal light scattering size (typically half their wavelength) they become much more transparent.  For example, zinc oxide becomes transparent at below 200 nm whereas titanium dioxide becomes transparent at sizes around 10-20 nm.  This makes formulating with zinc oxide much easier to achieve transparent formulations but harder to reach high SPF due to its performance in the UVB region.

Sometimes the so-called “boosters” can help many formulators resort to using salicylates as UVB boosters in their formulations.  Butyl octyl salicylate is not an approved sunscreen in the US but many formulators use it to boost their inorganic sunscreen SPF while claiming no organic sunscreens added.

Dispersion versus powder

The choice to use inorganic sunscreens as powder or dispersions in formulations is a very polarizing decision and many formulators prefer to use one type over the other.  In general, dispersions claim to have a smaller primary particle size which results in better dispersion of the pigment into the emulsion and leads to higher SPF and less whitening on the skin.  However, dispersions come at about 50% w/w solvent/pigment which limits the flexibility the formulator to tweak the formulation.  In addition, when working with w/o or w/Si formulations, it is harder to control the viscosity of such emulsions when using dispersions.  In these types of emulsions, the viscosity is built by the internal phase (water).  Using dispersions  ultimately increases the amount of external phase and reduces the amount of water used which will make such emulsions less viscous and less stable.

The use of powders, on the on the other hand, gives the formulator a lot of flexibility and reduces the cost of the formulation.  Although, when using powders, it is important to have manufacturing capability to grind the pigments at the factory scale to reduce agglomeration and produce formulations with good aesthetics.

Selecting emulsion type

Most inorganic sunscreen formulations on the market are w/o or w/Si emulsions.  These types of emulsions are much easier to preserve, as you only preserve the internal phase, and their pH does not fluctuate since they are anhydrous.  These types of emulsions inherently have very good water resistance as well.  Some of the drawbacks of w/o emulsions are their greasy feel mainly imparted by the surfactants and co-surfactants used. They tend to be more whitening on the skin and harder to spread.  W/Si emulsion have a superior end-feel, but they are not particularly biodegradable or earth-friendly by today’s standards.  They share the same characteristics as w/o emulsions when it comes to preservation, pH and water resistance.  In general w/Si emulsions are harder to stabilize and require the use of more than one surfactant to obtain stable emulsions.

It is very rare to see o/w emulsion formulations on the market, since they are harder to preserve and stabilize.  The presence of zinc oxide ultimately shifts pH towards 7.5 which renders most preservatives less effective.  In addition, at that pH very few polymers work well at stabilizing such emulsions especially naturally derived polymers.  On the other hand, these emulsions typically have a nicer feel on the skin and could be cost effective.

Adding a film former or SPF booster

Selecting a film-former or SPF booster for the emulsion is a critical step and one that should not be avoided.  The selection of the appropriate polymer depends mostly on the experience of the formulator and the in vivo results previously obtained with such polymer.  Many polymers are marketed to the formulators and some of them could work in one formulation or another.  However, it is crucial that the film former works across many formulations and especially in vivo since such tests are quite costly and hard to schedule.  As scientists, we should always test the formulations in vitro for water resistance and SPF to ensure that the addition of the polymer will give the desired results.  This will enable the formulator to refine the level of polymer in the emulsion as well.

In conclusion, I hope I shed some light on formulating inorganic sunscreen emulsions and I leave it up to the creativity of formulators to create excellent formulations with great aesthetics and high SPF.


Dr. Fares started his career in personal care studying the effect of solvents on sunscreen chemicals.  His interest in skin drug delivery especially from polymeric matrices grew during his graduate work at Rutgers, where he received his Ph. D.

Dr. Fares worked at Block Drug and GlaxoSmithKline where he held positions in research and development in the areas of skincare and oral care.  After that, he joined L’Oréal where he held several positions of increasing responsibility leading to AVP of skincare.  He is currently the Senior Director of skincare and oral care at Ashland Specialty Ingredients.  Dr. Fares is the author of many publications, and patents and made many presentations in national and international meetings in the areas of suncare, skincare, and oral care.  Dr Fares chairs the NYSCC scientific committee and has won multiple awards in the areas of sun care and polymer chemistry.

Supplements in the beauty industry – not just vitamins and minerals

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments

The recent introduction of holistic wellness as a major component of “I feel better and I look better” is not new to the beauty and cosmetic market. However, the explosion of nutritional formulations in the space of beauty from within is today associated with more robust and convincing scientific evidence than in the past. Supplement formulations appear more complex and not limited to collagen, vitamins and minerals to cite some of the most popular ingredients. The introduction of phytochemicals, sometime in the form of standardized plant extracts, along with vitamin and minerals, is providing an increased targeting and holistic approach to inner mechanisms associated with stress, diet, metabolism, aging, etc. that eventually influence our external look. This is not surprising as our cosmetic targets such as skin, hair, nail are part of our body and therefore react to our body unbalance. The connection between our gut and our skin, when a diverse gut environment is associated with skin conditions such as acne, psoriasis, atopic dermatitis, etc.1 and the influence of hormonal and stress-induced changes that can trigger hair conditions such as androgenetic alopecia and telogen effluvium.2 are some examples.

Modern formulations would use a wide range of ingredients that, when ingested, specifically target biological mechanisms associated with our health and wellness as well as our look (and I underline the specificity). It is possible then to create formulation that when tested deliver real efficacy and stand up to the claims.

Natural ingredients are taking center stage in these formulations, also inspired by the use of naturals in traditional medicine, with the possibility to merge knowledge from the western and eastern world.

When having a closer look at the applications and studies of supplements targeting wellness and beauty, recent reviews have highlighted their use as adjuvants and/or treatment for different dermatology or cosmetic conditions such as hair loss, acne, skin aging3-5. Since supplements are not FDA regulated, large, peer-reviewed clinical studies are necessary to determine the efficacy and safety of these supplements, especially since most of them haven’t been clinically tested. To avoid running lengthy and sometime expensive clinical trial, product manufacturers often rely on supplier’s data and/or academic literature about the ingredients in the final supplement composition. However, it is necessary to test the finish product since ingredient’s dosage and ingredients interaction and/or synergy can determine the outcome both from a safety and efficacy point of view. The quality of the clinical study is also important (number of subjects, inclusion/exclusion criteria, end points measures, data significance). Finally, Institutional Review Boards (IRB) approval is becoming increasingly in demand prior to the clinical study especially if dealing with compositions that are new to the market and carry some safety risk, and is often requested by scientific journals when trying to publish the data.

In conclusion, the cosmetic and the nutrition (supplements) industry are getting closer, with beauty as a shared target. Innovative supplement formulations carrying high end natural ingredients are becoming popular and demanded by the market. Rigorous science and testing is mandatory to make sure the formulation can survive scrutiny by the consumers and the FDA. Combination of topical and ingestible treatments in the beauty market will continue to grow in the following years.


  1. Ellis SR, Nguyen M, Vaughn AR, Notay M, Burney WA, Sandhu S, Sivamani RK. The Skin and Gut Microbiome and Its Role in Common Dermatologic Conditions. Microorganisms 7(11):550, 2019
  2. Hadshiew IM, Foitzik K, Arck PC, Paus R. Burden of hair loss: stress and the underestimated psychosocial impact of telogen effluvium and androgenetic alopecia. J Invest Dermatol. 123(3):455-7, 2004
  3. Adelman MJ, Bedford LM, Potts GA. Clinical efficacy of popular oral hair growth supplement ingredients. Int J Dermatol 60(10):1199-1210, 2021
  4. Clark AK, Haas KN, Sivamani RK. Edible Plants and Their Influence on the Gut Microbiome and Acne. Int J Mol Sci 17;18(5):1070, 2017
  5. Sardana K, Sachdeva S. Role of nutritional supplements in selected dermatological disorders: A review. J Cosmet Dermatol 21(1):85-98, 2022

Giorgio Dell’Acqua

Giorgio Dell’Acqua is Nutrafol’s Chief Scientific Officer. Part of the Leadership team, Giorgio spearheads the brand innovation, product formulation and scientific communication. After obtaining his PhD in Cell Biology in 1989, Giorgio worked in Academia for 15 years as an investigator in applied medical research. Moving to the private sector in 2000, he has spent the last 22 years as an executive and cosmetic scientist in the personal care industry. During his career, he directed R&D, Innovation, Science, and Product Development at multiple companies, including La Prairie and Kiehl’s. He has helped bringing more than 200 successful active ingredients and finished products to market, has authored more than 80 publications in medicine and cosmetic science, he holds 2 patents and has been a keynote speaker on clean beauty and natural ingredients. Giorgio serves on the NYSCC board as advisor.

The Dermal-Epidermal Junction

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments

The skin barrier function has recently dominated the cosmetic media and consumer market segment. The dermal-epidermal junction (DEJ) is a region within the skin which does not get a lot of face time relative to its high-profile neighbor (epidermis / stratum corneum). The DEJ is the birthplace of the epidermis so it seems reasonable to shed some light on light on this structure, and to ask some questions on why this skincare target may be under promoted for anti-age benefits. For this blog post we will use a marketing style “fact sheet” format to guide us through our chat on “The Dermal-Epidermal Junction”

What it is:

Many are aware of the well-known “brick and mortar” model of the epidermis. That structure (house) needs a foundation for stability and functionality. The DEJ is the foundation of the brick and mortar “house”. The DEJ is composed of four component areas:  the basal cell plasma membrane with its specialized attachment devices or hemidesmosomes,  an electron-lucent area, the lamina lucida,  the basal lamina, and the sub-basal lamina fibrous components, including anchoring fibrils, dermal microfibril bundles, and collagen fibers (1).  Hemidesmosomes (HDs) are highly specialized integrin-mediated epithelial attachment structures that make cells firmly adhere to the extracellular matrix by establishing a link between the underlying basement membrane (BM) and the internal mechanical stress-resilient keratin intermediate filament (IF) network (2). The next region progressing downward in the skin is the lamina lucida (LL), it is approximately 30–40 nm in width. This region is directly subjacent to the plasma membranes of basal keratinocytes. The layer underneath the LL is called the lamina densa (LD). This layer of the DEJ is 30-50 nm wide and has biochemical/physical interactions with the extracellular matrix (ECM) of the upper dermis (3).

Image Source Here


What It does:

The dermal-epidermal junction has several functions This area anchors the epidermis to the dermis and is responsible for the exchange of oxygen, nutrients and waste products between the vascularized dermis and the avascular epidermis. This connectivity between the epidermis and the dermis allows for a strong resistance against a possible physical stress (4). The DEJ provides both a structural support to keratinocytes and a specific niche that mediates signals influencing their behavior. The DEJ is also a highly interactive zone acting as a substrate for melanocyte/keratinocyte interactions for melanin distribution as well as a selective permeable barrier for epidermal and dermal cross talk in both directions.

Why isn’t the DEJ a more consistent focus of cosmeceutical product development:

The DEJ forms a fine line between the epidermis and dermis. It is known that the undulating rete ridge area becomes flatter with aging skin. This event lowers the surface area thereby decreasing cellular cross talk and nutrition movement in this region. The dermal capillary structures near the DEJ are a link to the human body and its systemic circulatory network. Could this be a cause of concern for cosmetic products? What if systemic absorption reduces a portion of the active from its sight of action? Another concern may be the potential for a portion of the cosmetic ingredients being moved in the body’s circulatory system. That is a “line in the sand” many companies may not want to cross. The DEJ is complicated, maybe the ability to produce some anti-age benefits in this region is outweighed by the complexity of the task.

Image Source: Kynan T. Lawlor, Pritinder Kaur: International Journal of Molecular Sciences 16 (12):28098-28107


How can the DEJ be evaluated or monitored?

If the DEJ is so important, how can we evaluate this area in a noninvasive fashion. One way is to look for a particular protein (Laminin 322) using immunofluorescence (5). Another option to evaluate the DEJ is to use Raman spectroscopy. This technique has been used to evaluate melanin distribution in vivo (6).

What are some DEJ biomarkers of interest for cosmetics?

The dermal-epidermal junction consists of a network of several interacting structural proteins that strengthen adhesion and mediate signaling events (7). Collagen VII stimulates renewal and improves cohesion of the DEJ. Collagen IV is a major constituent in basement membranes. It is involved in maintaining a functional interface between the epidermis and the dermis. Laminin 322 is a key target for DEJ anchoring and cohesion. Peptides have also been identified as opportunities to target to DEJ (8). With this said, there aren’t a lot of cosmetic brands positioning towards the DEJ.  The same can be said for raw materials suppliers, I didn’t find a lot of cosmetic materials targeting the DEJ.

In summary, targeting the DEJ can be challenging due to its location in the skin.  Caution should be taken as any intended influence of the DEJ from a topical strategy may become systemic due to the proximity of the circulatory/lymphatic vessels.  However, that disadvantage may be an opportunity to “feed” the DEJ from a targeted nutritional point of view from within.




R A Briggaman, C E Wheeler Jr : The Epidermal-Dermal Junction, J Invest Dermatol, 1975 Jul;65 (1):71-84

Gernot Walko et al. Molecular architecture and function of the hemidesmosome, Cell and Tissue Research 2015; 360(3): 529–544.

Eduardo Calonje , The structure and function of skin : McKee’s Pathology of the Skin, Chapter 1, 1-34.e3

Zhizhong Shen, Rete ridges: Morphogenesis, function, regulation, and reconstruction, Acta Biomaterialia Volume 155, 1 January 2023, Pages 19-34

Lincoln et al. : Gentamicin induces LAMB3 nonsense mutation readthrough and restores functional laminin 332 in junctional epidermolysis bullosa, National Academy of Sciences, PNAS | vol. 115 | no. 28 |

P . Yakimov et al. Melanin distribution from the dermal–epidermal junction to the stratum corneum: non‑invasive in vivo assessment by fluorescence and Raman microspectroscopy, Scientific Reports | (2020) 10:14374

Stephanie Goletz et al. Structural proteins of the dermal-epidermal junction targeted by autoantibodies in pemphigoid diseases, Exp Dermatolactions Dec;26(12):1154-1162. doi: 10.1111/exd.13446.

Sekyoo Jeong et al. Anti-Wrinkle Benefits of Peptides Complex Stimulating Skin Basement Membrane Proteins Expression, Int. J. Mol. Sci. 2020, 21, 73;

About the Author

Marc Cornell, BS. is a consultant at Mar-key Consulting LLC where he services the consumer product industry with innovative product development concepts.








Nanomaterial safety and regulations in personal care product development

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments


  1. Brief history of nanomaterial regulations

 According to Wikipedia, the word “nanotechnology” was first coined by Professor Norio Taniguchi of Tokyo University in 1974. He used it to describe semiconductor processes such as thin film deposition and ion beam milling, which exhibit characteristic control on the order of a nanometer.  Since the 1980s, the term nanotechnology has been referring to the fabrication, use/manipulation, control and characterization of structures devices or materials with a least one dimension in the size range of 1–100 nm. 1,2

Nanotechnologies represent a fast-growing market, bringing with them a combination of benefits, promises, risks, and uncertainties.  It is synonymous with high technology and high efficacy. It has often been used as a buzzword in advertisements and label claims of many consumer products, including personal care products, to gain attention.  Various physical and chemical properties of a material can be affected by its particle size. Nanomaterials have been engineered to have enhanced properties and performance that are beyond their non-nano counterparts. However, these much enhanced properties also raises questions about their safety.

In June 2007, the safety of nanomaterials such as nano TiO2 in sunscreen and fulluerene was raised in the article, Nanotechnology, the untold promise, and unknown risk, in Consumer Reports.  In August 2007, Friend of Earth (FOE) published Technology and Sunscreens, raising the particular concern over nano TiO2 and ZnO in sunscreens and calling for labeling and regulation of nanomaterials in consumer products. Earlier in 2006, a coalition of environmental and consumer groups, including the International Center for Technology Assessment, Friends of the Earth, and Our Bodies, Ourselves, filed a legal petition with the Food and Drug Administration (FDA) asking FDA to regulate nanotechnology.

The first regulatory move was made by European Commission (EC).   EC acknowledged the safety concerns considering that nanomaterials could have very different physical and chemical properties over their non-nano counterparts, potentially resulting in different toxicological profiles. In 2005, the EU Scientific Committee on Consumer Products was requested by EC to provide a scientific opinion on the safety of nanomaterials in cosmetic products, in particular, the appropriateness of existing methodologies to assess the potential risk associated. This created public fear regarding nanomaterials in consumer products, especially in personal care products. In the meantime, the uncertainty of the future regulatory landscape made it extremely difficult for cosmetic formulators to incorporate nanomaterials in any formulation.

In 2009, REGULATION (EC) No 1223/2009 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 30 November 2009 on cosmetic products stated the purpose and need of a definition of nanomaterial, which has been evolving since. Most recently, COMMISSION RECOMMENDATION of 10 June 2022 on the definition of nanomaterial, C 229/1, defines nanomaterial as follows:

Nanomaterial means a natural, incidental, or manufactured material consisting of solid particles that are present, either on their own or as identifiable constituent particles in aggregates or agglomerates, and where 50 % or more of these particles in the number-based size distribution fulfill at least one of the following conditions:

– one or more external dimensions of the particle are in the size range 1 nm to 100 nm;
– the particle has an elongated shape, such as a rod, fibre or tube, where two external dimensions are smaller than 1 nm and the other dimension is larger than 100 nm.
– the particle has a plate-like shape, where one external dimension is smaller than 1 nm and the other dimensions are larger than 100 nm

Moreover, Article 16 of Regulation (EC) No 1223/2009 on cosmetic products requires that, in addition to the notification under Article 13, cosmetic products containing nanomaterials shall be notified to the Commission by the Responsible Person using electronic means six months prior to being placed on the market. Notification should be done on Cosmetic Products Notification Portal (CPNP).


  1. Interpretation of nanomaterial definition:

The interpretation of the nanomaterial definition depends to a large extent on the size measurement method. Because of the structural complexity of nanomaterials, no single test method is capable of measuring all nanomaterials precisely and properly. EC recommends determining nanomaterial by its primary particle size or internal structure while allowing sectoral interpretation according to the actual use conditions, which may vary drastically from industry to industry.

In 2011, Cosmetic Europe issued their own interpretation of EC definition of nanomaterial, and then an update in 2019, stating that “materials with constitutive elements having a dimension in the nano-range (e.g. aggregates, agglomerates, composites) but that are themselves greater than 100 nm in size should not be considered as nanomaterials unless they release nano-objects or aggregates of less than 100 nm in size in cosmetic products under normal use conditions”.  Accordingly, the size of aggregates or agglomerates is used to determine the nanomaterial for labeling cosmetic products. This interpretation has been followed by many cosmetic companies.


  1. Commercial use of nanomaterials

According to a EC’s report, Sub-working group of on nanomaterial definition, published on January 28, 2021, 37,647 cosmetic products were notified with nanomaterials in EU market, (via Art.13 procedure), which corresponds to about 1.5% of all notifications. According to 2015 – 2020 data, on average, about 10 new cosmetic products containing nanomaterials are placed on the EU market every day.

Most common product categories with nanomaterials: (64% of all nanomaterials notifications):

  1. Sun protection
  2. Nail varnish/nail make up
  3. Oxidative hair care
  4. Foundation
  5. Lip care products and lipsticks

The most used cosmetic ingredients are reported below (4 ingredients accounts for over 70% of all CPNP notifications):

  1. Titanium Dioxide
  2. Silica Dimethyl Silylate, Silane, dichlorodimethyl-, reaction products with silica
  3. Carbon Black nano (CI77266)
  4. Silica

Scientific Committee for Consumer Safety (SCCS) under European Commission is requested by EC to evaluate the safety of the listed nanomaterials via a process that was based on the scientific literature available at the time and SCCS’ expert judgment. In early 2021, SCCS published an advice on the safety of nanomaterials in cosmetics, in which nanomaterials of concern were separated into two groups. 3

     — 16(4) of the Cosmetics Regulation

28 substances including silica, Titanium dioxide, Zinc oxide, Methylene Bis Benzotriazolyl Tetramethylbutylphenol were listed in the appendix 1 in an order of priority according to risk potential (based on a number of criteria).

     — 16(6) of the Cosmetics Regulation

SCCS reviewed three previous inclusive opinions on colloid silver, nano styrene/acrylate polymer and nano silica, and identified certain aspects relating to each of these nanomateirals that raised safety concern.


  1. Nano TiO2 /ZnO in sunscreens

For personal care products, nano TiO2 and ZnO are perhaps the two most concerning ingredients due to their wide use as sunscreen actives. Because of their very small primary particle size, nano TiO2 and ZnO are much more transparent on the skin and much more potent in UV protection than their non-nano or pigmentary counterparts. For instance, pigmentary TiO2 is known to be completely opaque and cannot be used in any skin care product for effective UV protection.  Nano TiO2, with a primary size of 10 – 20 nm, is not only highly transparent but also provides 5 – 6 times higher SPF.   For this reason, nano TiO2 and ZnO have been used widely in sunscreen products in Japan and Australia since 1980s.  They have been popular among those having sensitive skin and allergic to organic sunscreens.

Up to now, and after the use by hundreds of millions of consumers, there have been no reports of any adverse health effects for nano TiO2 and ZnO. However, they were still put under great scrutiny due to the general concerns and fear that were raised for nanomaterials in early 2000s.  Many customers, especially in EU, became somewhat nanophobic at the time as the future of regulatory landscape remained uncertain.

For topical application, the major concern is transdermal adsorption or penetration.  After years of study, SCCS issued in 2012 OPINION ON Zinc oxide (nano form) COLIPA S76 stating thatThere is no evidence for the absorption of ZnO nanoparticles through skin and via the oral route. Even if there was any dermal and/or oral absorption of ZnO nanoparticles, continuous dissolution of zinc ions would lead to complete solubilization of the particles in the biological environment.” 4 Two years later, the SCCS issued the OPINION ON 22 on Titanium Dioxide (nano form), stating “the main consideration in the current assessment is the apparent lack of penetration of TiO2 nanoparticles through skin.” 5

Another concern is photo-catalytic activity of nano TiO2 that lead to generation of free radicals and ensuing oxidation.  Surface treatment of nano TiO2 had been quite common, and the data collected by SCCSs on commercial grades confirmed that the photo-catalytic activity could be much suppressed by surface treatment.

Finally, EU revised the nano TiO2 monograph for use as UV filters in 2016. The key updates included a list of allowed surface treatments and a limit on the photocatalytic activity. In the same year, ZnO was officially approved as an UV filter, and a list of surface treatments and solubility specification were included in the monograph. 6

After years of investigation, EC finally concluded that nano TiO2 and ZnO were safe for personal care use as long as:

  1. They comply with the specifications in the EU monographs.
  2. The final product will not lead to exposure of the end-user’s lungs by inhalation.

For other nanomaterials under review, the SCCS has yet to establish final opinions. The future regulatory status remains uncertain.


  1. Regulations in other regions

Nanomaterial is generally defined as a material with internal or external dimensions in the range of 1 – 100 nm in other regions.   Many regulatory agencies share similar concerns to EC’s, but they have not acted as swiftly as EC.  Although there are guidelines for considering the safety of nanomaterials, there are few laws enacted to regulate them.  To the author’s knowledge, there are two regulations outside EU:

A) Canada – If a sunscreen product contains only inorganic UV filters, nano TiO2 and/or ZnO, it is considered a Natural Health Product, for which the premarket approval is not needed. However, if any of the two is used with organic UV filters, the sunscreen is a drug product. Safety of nano TiO2/ZnO needs to be addressed and approved, which can be painstaking. Further, there is no official test method and threshold for classifying nanomaterials.

B) China – “Regulations on the Supervision and Administration of Children’s Cosmetics” issued by the State Food and Drug Administration (2021 No. 123), was issued in 2021. Section 7.1 states that:

“….. New raw materials that are still in the monitoring period should not be used, and raw materials prepared by new technologies such as genetic technology and nanotechnology should not be used. If there is no alternative raw material that must be used, the reason should be explained, and evaluate the safety of children’s cosmetics”.

Since nano TiO2 and ZnO are not new technologies, they could be exempted from this regulation. However, the ambiguity in interpreting the regulatory language and difficulty in effective communication with Chinese officials have made many company shy away from nano TiO2 or ZnO, and instead turning to the non-nano grades.


  1. Summary

Nanomaterial safety and regulations are important to personal care product development. Many nanomateterials used in our industry are under safety review and their future is uncertain. As far as nano TiO2 and ZnO are concerned, it is official that they are safe as long as they are not exposed to end-users’ lung in application. Due to the complex structures of nanomaterials, their size analysis method, data interpretation and regulatory classification have been constantly investigated and are still evolving. Formulators are highly advised to consult with their regulatory experts as well as the suppliers when choosing nano or non-nanomaterials.



  1. (2007a) Opinion on: the Scientific Aspects of the Existing Proposed Definition Relating to Products of Nanoscience Nanotechnologies. Brussels: European Commission Health Consumer Protection Directorate General.
    SCENHIR. (2007b) Opinion on: the Appropriateness of the Risk Assessment Methodology in Accordance with the Technical Guidance Documents for the New and Existing Substances for Assessing the Risk of Nanomaterials. Brussels.
  1. ISO/TS 27687. (2008). Nanotechnologies – Terminology and Definitions for Nano-objects – Nanoparticle, Nanofibre and Nanoplate.
  2. SCCS/1618/2020 Scientific Advice; https://health.ec.europa.eu/system/files/2022-08/sccs_o_239.pdf
  3. SCCS/1489/12; https://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_103.pdf
  4. SCCS/1516/13 Revision of 22 April 2014; https://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_136.pdf
  5. COMMISSION REGULATION (EU) 2016/1143 of 13 July 2016, amending Annex VI to Regulation (EC) No 1223/2009 of the European Parliament and of the Council on cosmetic products

A stem-cell based approach against photoaging

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments

We have all heard the term “photoaging” and can agree on its definition, succinctly described by the Canadian Dermatology Association: “Photoaging is premature aging of the skin caused by repeated exposure to ultraviolet radiation (UV), primarily from the sun but also from artificial UV sources. Photoaging differs from chronologic aging: the damaging effects of UV rays – from the sun or artificial tanning sources – alter normal skin structures.”(1) As a result, this UV light causes DNA changes at a cellular level, and because photodamage happens in the deepest layers of the skin – the dermis – it can take years before the damage surfaces and becomes visible(2). (As we all know, UVA radiation is highly damaging, penetrating much deeper than UVB radiation; while UVB causes sunburn, UVA results in premature skin aging and wrinkle formation – and both, of course, can cause skin cancers(3).) Historically speaking, our industry has long focused on protection against UV radiation via the use of sunscreens (which remain on the surface of the skin), but later scientific advances have produced ingredients and formulations intended to penetrate the skin and act to protect cells in the dermal and epidermal layers. And the most recent efforts have been concentrated on the protection of keratinocyte stem cells in the epidermis against UVA-induced DNA lesions, along with boosting the cells’ endogenous DNA-repair system.

It must be mentioned that the concept of “stem cells” commonly brings to mind embryonic stem cells, which can form new cells of any kind, but here we are referring to epidermal stem cells, which can only differentiate into keratinocytes. And as we know from basic skin biology, keratinocytes – if healthy – can potentially renew indefinitely, providing a continuous supply of new cells to the epidermis as part of the essential renewal process of the skin.

But back to the topic of UVA protection: It has been shown that epidermal stem cells have a greater capacity to fight against UVA aggression than their “daughter”, or differentiated, cells, due to more efficient repair mechanisms(4). By the same token, epidermal stem cells are highly sensitive to UVA-induced damage and lose their “stemness” potential when exposed to excessive UVA radiation, which is why it is of utmost importance to protect these stem cells so that they remain robust and productive. It has recently been discovered that an extract from the fruit sechium edule can provide significant biological protection to these stem cells against UVA-induced epidermal damage(5).

The protective effect of sechium edule fruit extract on the epidermis can be observed through its protection against UVA-induced DNA damage, boosting of DNA repair capacities, and maintenance of the stemness potential of keratinocytes.

It was found that exposure to UVA induces the formation of oxidative DNA lesions, specifically 8-oxoG lesions, in keratinocyte cells and causes extensive damage to DNA in the form of fragmentation. A study conducted with the comet assay showcases the severity of UVA-induced damage on DNA as visualized in the samples exposed to UVA with the fragmented DNA forming a tail behind intact DNA. Treatment with sechium edule fruit extract helps to protect keratinocytes by significantly reducing the number of oxidative lesions thereby helping to keep the DNA intact (see Figure 1).

Figure 1. Protection against UVA-induced DNA damage (***p<0.001) (6)

As mentioned earlier, the human body is equipped with its own endogenous repair mechanisms that can repair DNA, but these mechanisms can often be affected by UV and become less effective. The next study looked at the enzymes involved in the repair of 8-oxoG lesions, OGG1 & MYH. The treatment of keratinocytes with the extract brought about a significant increase in the mRNA expression of both OOG1 and MYH suggesting an increase in the DNA repair capacities (see Figure 2).

Figure 2. Increase in enzymes associated with DNA repair capacities of 8oxo-G lesions (***: p<0.001; *: p<0.05) (6)

The most important aspect of protection against photoaging is the preservation of the stemness potential of keratinocytes to ensure proper epidermal homeostasis. The last study observed the ability of keratinocyte stem cells to multiply and form new keratinocytes. In the graph below, holoclones refer to cells capable of extensive proliferation and meroclones are cells with limited proliferation capacity. You can think of holoclones as keratinocyte stem cells and meroclones as daughter cells.

When exposed to UVA, the holoclones change into meroclones and the number of colonies drastically decreases, showcasing that the stemness potential has been negatively impacted by UV exposure and the self-renewal capacity lost. In comparison, holoclones treated with the extract of sechium edule fruit and exposed to UVA present a significant increase in number of colonies and the stemness potential of keratinocytes preserved (see Figure 3).


Figure 3. The preservation of stemness potential in keratinocytes (6)

In conclusion, when the “stemness” potential of the keratinocytes is preserved it results in proper skin homeostasis and can lead to improved skin appearance (smoother skin, reduced wrinkles, more even skin tone, etc.). In addition to the use of broad-spectrum sunscreens (always recommended!), an active such as the one described above derived from the fruit of sechium edule is another tool in the arsenal of the formulating chemist in the ongoing fight against the effects of photoaging and UV-damage.


  1. dermatology.ca
  2. yalemedicine.org
  3. uihc.org
  4. Metral, Elodie, et al., “Keratinocyte stem cells are more resistant to UVA radiation than their direct progeny.” PLOS ONE, 2018 Sept, vol. 13, n° 9, https://doi.org/10.1371/journal.pone.0203863
  5. Metral, Elodie, et al., “Long-term Genoprotection Effect of Sechium edule Fruit Extract Against UVA Irradiation in Keratinocytes.”, Photochemistry and Photobiology, 2018 Mar; 94(2): 343-350, https://doi.org/10.1111/php.12854
  6. Metral, Elodie, et al. “Long-Term Genoprotection Effect of Sechium Edule Fruit Extract against UVA Irradiation in Keratinocytes.” Photochemistry and Photobiology, 2018 Mar; 94(2): 343-350, https://doi.org/10.1111/php.12854



Ben Blinder is the Executive Director, Business Operations at Gattefossé USA, with P/L responsibility for the personal care and pharmaceutical business units in the US and Mexico. He is also a founding member of the Advisory Committee on Diversity & Inclusion for Gattefossé in North America. Ben holds a BS in chemical engineering from Lehigh University.


Christina Philips is the Technical Marketing Leader at Gattefossé USA, responsible for providing information on trends and customer insights and technical marketing support for the sales team. She works closely with formulation chemists at the North American Technical Center to provide customers with informative lab sessions and conceptualize sensorial prototypes that highlight the company’s ingredients. She also volunteers as the Director of Empowerment for FOREFRONT Charity. Christina holds a BS in cellular and molecular biology from the University of Connecticut.

Silicone Alternative Solutions for Hair Care

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments



Silicones have been widely used in the cosmetic industry for decades. They are exceptionally versatile and impart multifaceted benefits across a wide range of beauty and personal care products. Not all silicones have been created equal, however, and some of these materials are now limited by regulatory restrictions on their use. Due to an increasing focus on their toxicological and environmental impact, consumers are now gravitating towards natural, safe, and sustainable alternatives. This article provides an overview on how silicones have shaped the hair care industry and the continuous research necessary to find innovative and environmentally friendly alternatives to silicones.

Influence of Silicones in the Hair Care Industry

Silicones have been important ingredients in hair care products since the 1950’s. Silicones or silicone derivatives are widely used in shampoos, conditioners, colorants, or styling products where they act as either emollients, humectants, film formers, antifoaming, anti-static, or binding agents [1]. These materials range from basic cyclic or linear polydimethylsiloxane (PDMS) to polyether-and amino-based fluids and silicone resins [2]. All silicones have a natural origin (silica), but synthetic processes are used to create the plethora of silicone ingredients used in cosmetics [3].

Linear PDMS, also known as dimethicone, is available in a range of molecular weights and viscosities and is most used in hair care applications. They provide excellent conditioning and performance which increases with higher viscosity. Use of dimethicone reduces combing forces, provides great sensory benefits like gliding, and adds suppleness to hair.

Phenyl trimethicone is also based on linear PDMS with the addition of phenyl groups [4]. This combination results in a higher refractive index that effectively coats the hair enhancing its shine and leaving hair soft. PDMS polymers are also highly water resistant which makes them effective agents in reducing tackiness of the formulations.

Cyclic polydimethylsiloxane (cyclic PDMS) or cyclomethicones fluids are characterized by ring structures typically containing three to six groups per ring [2]. These fluids decrease combing forces by reducing friction and surface energy [4]. Due to their volatility and fast spreading properties, they provide transient gloss to hair, leaving hair weightless and without any build-up. Cyclomethicones are more compatible with a wider range of ingredients versus linear PDMS.

Silicone gum/fluid blends provide a high level of substantive conditioning and frizz control while imparting a soft and lubricious feel [4]. There are silicones that are modified, like amodimethicones (amine-functionalized silicones) or alkylmethicones (replacing methyl groups on PDMs with alkyl chains) which are widely used in hair care applications as well. Amodimethicones impart specific benefits like color protection, heat protection, repair, reduced flyways, and deep conditioning.

The above-mentioned silicones are non-water soluble, whereas silicone polyethers are a family of water and/or alcohol soluble materials commonly used in shampoo formulations. They provide light to medium conditioning. In addition to acting as emulsifiers or co-emulsifiers, they can be used as resin modifiers to aid curl retention [2].

Moving Away from Silicones

While silicones have been highly effective hair care ingredients providing both functional and enhanced sensorial benefits, there is a movement away from their use due to a variety of reasons. There are long-term effects of silicone such as causing build-up, greasiness, and scalp accumulation [5]. Furthermore, concerns have been raised about their toxicity and effects on the environment.

The Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) assessed the potential environmental effect of cyclic silicones: cyclotetrasiloxane (D4) and cyclopentasiloxane (D5). Based on the evaluation, D4 meets the criteria for identification as a persistent, bio accumulative and toxic (PBT), very persistent, very bioaccumulative (vPvB) substance and D5 meets the criteria for a vPvB substance [6]. After January 31st, 2020, the concentration of D4/D5 in rinse-off cosmetic products placed on the market should be less than 0.1% by weight of either substance. This has now been amended to include cyclohexasiloxane (D6) and is expected to be further restricted to include leave-on products [7].

Linear silicones are also not completely in the clear. They are suspected to be an environmental toxin and to be bioaccumulative. Dimethicone, Dimethicone Copolymer, Polysilicone-15 and other silicones are commonly considered to be microplastics [8,9]. In addition to being non-biodegradable, silicone oils also have an impact on the environment due to their industrial production process which has a high carbon footprint [10].

High performance, Natural and Sustainable Solutions

According to Mintel’s GNPD, between 2016 and 2021 the incidence of “silicone-free” claims for hair care products increased by over 200%. With regulations to control the usage of silicones in hair care products and a growing emphasis on naturality and sustainability, companies are looking for ingredients that serve as silicone alternatives. There is a huge focus on developing efficient and innovative ingredients that offer similar or better functional performance and with a better sensorial profile than silicones. A few ingredient solutions currently offered are highlighted below:

C13-C15 Alkane (plant-derived) is a sustainable natural silicone replacement developed via the fermentation of renewable sugar and grown sustainably without irrigation. This ingredient meets the performance of dimethicone in frizz reduction and color protection. It also matches the performance of amodimethicone in terms of wet/dry combability and provides an excellent sensorial profile. Ethyl Macadamiate is another silicone alternative of macadamia esters. It is biodegradable and provides the same silky, smooth after feel as cyclopentasiloxane [8]. A highly viscous, hydrogenated polyfarnesene presents interesting properties to replace Dimethiconol-based blends [11].

A prime function of silicones is to act as emollients. A vegetable emollient that is readily biodegradable and reduces significant carbon footprint is a perfect ally to protect hair from repeated mechanical stress and perform superior to cyclopentasiloxane [10]. An example is Hydrogenated Olive Oil which is an unsaponifiable squalene from olive oil and hydrogenated castor oil. It is yet another emollient offering to replace silicone and mineral oils that has great application in anti-frizz haircare products [12].

Reduced Silicone Solutions

It is not necessary to exclude all silicone products; cyclic free or synthetic silicones that meet REACH requirements can still be used as alternative solutions. Using low viscosity dimethicone and a mixture of C13-C14 isoparaffin can be considered as a replacement for cyclomethicones delivering a similar sensory profile [7]. Use of terminal hydroxy amino-modified silicone (THA) chemistry provides long-lasting conditioning and protects hair against breakage [13]. As for synthetic offerings, combining quaternary conditioning properties of cetrimonium chloride with a carboxylated silicone provides thermal protection and enhances the manageability of hair, while a complex of cetrimonium chloride with a water-soluble silicone provides great hair care benefits in different formats [7]. A combination of natural oils and a synthetic polymer can enhance and extend the benefits of natural oils to smooth and restore damaged hair and protect and reduce hair damage from different grooming regimens [12].

The industry also offers some unique solutions like quat-free polymeric conditioning additives that can provide multi-functional benefits to hair which are ideal for amodimethicone free formulations. Lastly, to reduce the carbon footprint, manufacturers are cutting down the high use of energy to produce dimethicones of various viscosities by using methanol obtained from biomass instead of fossil fuels [7].

Using Digital Tools to Source Ingredients

In the quest for clean and sustainable ingredients, Artificial Intelligence (AI) is playing a critical role in research and development. Machine learning is a powerful tool that can collect large amounts of data and provide detailed information about ingredient sourcing [11].  AI will be further integrated to explore unmet needs and help screen and identify innovative ingredients for various applications. Companies are also developing apps, using QR codes to trace ingredients, and promote ingredient transparency by providing origin and sustainable properties [11].


Over the last decade, there has been a strong shift in consumer product preferences with emphasis on personal wellbeing and the environment. The cosmetic industry has made great progress in offering many eco-friendly, clean, and sustainable solutions not only to replace silicones but also other ingredients that are currently being challenged. Companies are tasked to continue their efforts in developing eco-friendly and sustainable products that are highly effective in functional and sensorial performance to meet consumer needs.


  1. Kostic A, “Silicones in cosmetics and their impact on the environment”, Cos ACTIVE J. 2021;1:34–39
  2. Katie Schaefer, “Silicones in Hair Care: Making Innovative Solutions Possible”, Cosmetics & Toiletries (November,2008)
  3. Megan McIntyre, “Do Silicones Deserve Their Bad Rap? “, Beauty Independent, June 2019
  4. Bethany Johnson, Kevin Murphy and Feifei Lin, “How Silicones Shape the Hair Care Industry: A Review”, Cosmetics & Toiletries (June,2015)
  5. Solvay.com, “How Sulfate and silicone Alternatives Improve the Hair care Industry and Benefit Consumers”
  6. Mojgan Moddaresi, “Regulation Update: Cyclosiloxanes in the EU”, UL Prospector (February ,2018)
  7. Smooth closer: The latest in silicones and silicone alternatives”, Cosmetics Business (November,2021)
  8. SuperZero.com, “What are silicones and why are silicones used in the beauty industry? (April,2021)
  9. Plastic-TheHiddenBeautyIngredients.pdf (beatthemicrobead.org)
  10. “An alternate to silicone for hair care”, Personal Care Magazine (March,2019)
  11. “New generation of emollient showing promising results as a sustainable alternative to viscous silicones in hair care formulations: Seppic”, Cosmetics & Toiletries, Vol.137, No.6 (June 2022)
  12. John Woodruff, “Silicones and Alternatives 2018”, published by SPC2018
  13. Nisaraporn Suthiwangcharoen, Bethany Prime, Beth Johnson, and Dawn Carsten, “Simple and Sensorial Amino-modified silicone protects and revives hair”, Cosmetics & Toiletries, Vol.136, No.2 (February 2021)


Mythili Nori has worked in the Personal Care industry for over a decade. Her expertise is in Product Claim Substantiation and Data Science. In her current role at BASF, she is responsible for Physical Claim Substantiation & Sensory testing for Hair & Skin Care. Prior to joining BASF, she spent 5 years at TRI/Princeton as a Senior Research Associate, supporting claim substantiation and fundamental research activities for textile and hair surfaces. She earned a Bachelor of Technology in Chemical Engineering from India and received Master of Science in Chemical Engineering at North Carolina Agriculture & Technical State University focusing on purification of drinking water.

PPARs reemerging as a skin wellness target in cosmetics

by james.runkle@drummondst.com james.runkle@drummondst.com No Comments

PPARs reemerging as a skin wellness target in cosmetics

Written by Marc Cornell, Mar-Key Consulting LLC

Cosmetics are continuing their marvelous evolution with new scientific findings and breakthrough innovations. Sometimes we need to look back to find the genesis of a current marketing or positioning trend. Take a step back with me to the late 20th century, where a young researcher (MC) was being educated in the biology of wound healing. During this time, I became aware of Peroxisome proliferator-activated receptors (PPARs). PPAR-alpha expression plays a role in the inflammatory stage of wound healing. Later I learned wound healing shares many biologic pathways with anti-age biology.  Peroxisome proliferator-activated receptors is a mouthful, right? Let’s dial it back bit and keep the PPAR focus on our body’s largest organ, the skin.

PPAR’s are ligand inducible transcription factors belonging to the nuclear hormone receptor superfamily. The key isoforms of PPARs are notated as (alpha), (beta/delta) and (gamma). These forms can up regulate or down regulate many cellular and metabolic processes (cellular differentiation, proliferation, lipid homeostasis and energy metabolism). These functions are critical to our body and its skin’s immune system, epidermal barrier function and development of pro-inflammatory signals. Peroxisome proliferator-activated receptors (PPARs) are also involved in regulating glucose, lipid homeostasis and modulate mitochondrial function. (1)  It is obvious that regulation of PPAR signaling to various biological systems is an opportunity for medicine and cosmetic science

In some publications, regulation of PPAR signaling have been linked to disease pathogenesis. These ailments have complex causes involving genetic, environmental, and nutritional factors, PPARS are just a part of the pathway. (2) In cosmetic science we are careful to draw the line between drug and cosmetic claims. With that said, there are numerous scientific studies elucidating shared connections between drug and cosmetic active biologic modes of action.

Now we take a partial deep dive on the FAQ’s for PPARS.  From there we will highlight how targeting PPAR’s has been around for some time in cosmetics. More recently these chemistries are trending in a big way as clinical branded cosmetics remerge as part of the wellness positioning.

How can cosmetic science leverage PPARS to facilitate skin wellness? We start our PPAR discussion by looking at the skin barrier function. This area of skin biology is also part of a recent trend towards positioning and the minimization of environmental stressors on the exposome. The exposome is defined as the measure of all the exposures of an individual in a lifetime and how those exposures relate to health.  PPAR activation has been shown to have an important role in skin barrier function by regulating differentiation and lipid synthesis in keratinocytes. (3) This fact fits nicely into homeostasis wellness positioning.

PPAR activation takes place through heterodimerization.  Simply put, you need 2 ligands to come together on the DNA to initiate gene regulation.  PPAR activators are already being used in areas of cosmetic science application.  Botanical extracts have been shown to activate PPAR in the stimulation of collagen in skin (4). There is also evidence that PPARs may be used as an alternative to retinoids in skin care. (5) PPARs have an important effect in keratinocyte homeostasis, suggesting a role in diseases such as psoriasis. (6)   PPAR acts directly to negatively regulate gene expression of proinflammatory genes in a ligand-dependent manner by antagonizing the activities of transcription factors such as members of the NF-kB and AP-1 families. (7).  One very popular cosmetic application is the use of omega 3 fatty acids.  These are popular natural ligands for PPARα receptors and are key to preventing/reducing inflammation.

One critical factor in attempting to utilize pathways linked to PPARs is in the understanding of the up or down regulation of these biochemicals. Typical of any biologic system there is potential for biofeedback, so understanding the pathways and assay methodologies are important. Good news is gene expression and cell culture models now allow the high throughput analysis of materials which may take part in PPAR regulation. This fact and the numerous peer review publications give the cosmetic chemist a boost in the study of PPARs.

In closing I provide just a few key words for continued education on PPARs.

Links between PPAR and:

a) Endocannabinoid receptor system
b) Hyaluronic acid
c) Wound healing
d) Retinoid receptor system
e) UV modulated inflammation
f) Inflamaging
g) Mitochondrial function
h) and MORE!

  1. Ting-Wei Lee, Kuan-Jen Bai, Ting-I Lee, Tze-Fan Chao, Yu-Hsun Kao & Yi-Jen Chen : PPARs modulate cardiac metabolism and mitochondrial function in diabetes Journal of Biomedical Science volume 24, Article number: 5 (2017)
  2. Kersten S, Desvergne B, Wahli W. : Roles of PPARs in health and disease. Nature. 2000; 405: 421–4. NATURE
  3. Su-Hyoun Chon , Ruth Tannahill, Xiang Yao, Michael D Southall, Apostolos Pappas. Keratinocyte differentiation and upregulation of ceramide synthesis induced by an oat lipid extract via the activation of PPAR pathways , Exp Dermatol. 2015 Apr;24 (4):290-5
  4. George P. Majewski1 | Smrita Singh2 | Krzysztof Bojanowski :Olive leaf-derived PPAR agonist complex induces collagen IV synthesis in human skin models, Int J Cosmet Sci. 2021;43:662–676
  5. John Simon Craw, George Majewski: Coding Skin for Care: PPAR Ligands as Retinoid Alternatives and Adjuvants—Cosmetic and Toiletries, Jan 6th, 2022
  6. Emerson de Andrade Lima1 et al : Peroxisome proliferator-activated receptor agonists (PPARs): a promising prospect in the treatment of psoriasis and psoriatic arthritis* An Bras Dermatol. 2013;88(6):1029-35.
  7. Yuval Ramot et al, The role of PPAR-mediated signaling in skin biology and pathology: new targets and opportunities for clinical dermatology : Experimental Dermatology, 2015, 24, 245–251


Written by Marc Cornell, Mar-Key Consulting LLC

Marc Cornell, BS. is a consultant at Mar-key Consulting LLC where he services the consumer product industry with innovative formulation concepts.  During his thirty-year career he has worked in an R&D role for large (Merck, L’Oreal, Bristol Meyers Squibb, Union Carbide) and medium sized companies (Neostrata, ChemAid Labs, KV Pharmaceutical). For the last ­20 years he has worked primarily on the research and formulation development of “Cosmeceuticals” for various brands (Skinceuticals, Neostrata, Dr. Perricone, Biomedic, Strivectin, and La Roche Posay). In this role he collaborated with researchers in skin biology and clinical testing to design, formulate and test novel cosmetic active delivery vehicles. Marc’s work has been patented and published in peer review journals and trade publications.