Arginine: A closer look at this amino acid widely used in cosmetology.

Arginine, an amino acid that constitutes many proteins in the body, plays a crucial role in various biological processes. It is particularly involved in the production of nitric oxide NO, a compound whose vasodilatory effect helps to stabilise blood pressure. Arginine is also attributed with properties ergogenic, due to its role in the synthesis of creatine. Naturally present in muscles, studies have shown that creatine can increase muscle strength as well as the size of muscle fibres. This is why there are many dietary supplements based on creatine and arginine intended for athletes.

First isolated in 1886 by the German chemist Ernst SCHULZE and his assistant Ernst STEIGER, arginine is found in various foods: legumes, cereals, meats, dairy products, fish, eggs... It can also be incorporated into cosmetic products and is indeed one of the most commonly used amino acids in the formulation of skin and hair care products.

The arginine found in cosmetic products is obtained through the fermentation of plant sugars by microorganisms. The most commonly used strains are Corynebacterium, Bacillus and Escherichia coli. A fermentation medium is prepared to provide the microorganisms with all the nutrients necessary for their growth and the production of arginine. This must be rich in glucose and ammonium sulphate. Ammonium sulphate provides a nitrogen source, necessary for the synthesis of arginine, an amino acid composed of 32% nitrogen. The fermentation takes place at a neutral pH, in the presence of oxygen.

Once the fermentation is complete, bacterial cells and proteins are removed using a membrane and impurities are eliminated through a ion exchange resin. This purification phase is necessary to isolate arginine. At the end of this process, very pure arginine crystals can be obtained by concentration. Their white colour is the origin of the name arginine, derived from the Greek árgyros meaning "silver".

Arginine exhibits a range of skin and hair properties that make it an interesting ingredient for formulating cosmetic care products.

• Arginine promotes the proper functioning of the skin barrier.

  It appears that arginine may contribute to the maintenance of the skin barrier by increasing the production of collagen and elastin. In doing so, this amino acid could also enhance the suppleness and elasticity of the skin and slow down skin ageing. It should be noted that this effect of arginine is currently under study and has not yet been confirmed.

• Arginine acts as an antioxidant.

  Several studies have shown that oral intake of arginine can stimulate the production of glutathione, an antioxidant molecule present in the human body. By protecting the body and skin from oxidative stress, arginine prevents skin disorders caused by free radicals such as hyperpigmentation or skin sagging. However, these effects of arginine are only proven with oral intake, further studies are needed to demonstrate them following topical application.

• Arginine has healing properties.

  Arginine plays a significant role in wound healing, from the inflammatory phase through to skin remodelling. By contributing to the production of nitric oxide, it helps regulate the proliferation and differentiation of epithelial cells and modulate angiogenesis, the process of blood vessel formation.

• Arginine stimulates hair growth while reducing hair loss.

  The arginine is also used to formulate hair and eyelash products. Several studies have shown that it can act on the hair/follicle cycle to stimulate growth and prevent hair/eyelash loss. This amino acid works particularly by protecting the fibres from the effects of dihydrotestosterone, a hormone that shortens their lifespan.

• Arginine has an alkalinising effect.

  Compatible with the majority of cosmetic ingredients, arginine has an alkaline pH, which means it can help balance the pH of formulations. It is important to control the pH of cosmetic care products to ensure they are compatible with the skin's natural acidity and do not disrupt the skin barrier.

To date, no side effects have been reported after using arginine for cosmetic purposes. This ingredient is considered safe and is not subject to a concentration limit by European cosmetic regulations, although it is generally incorporated into skincare products at concentrations ranging from 0.5 to 5%. Furthermore, arginine is well tolerated by individuals with sensitive skin and its use is not restricted for pregnant or breastfeeding women and young children.

Note : we are only discussing here the topical use of arginine. The oral intake of dietary supplements containing arginine involves taking other precautions and we advise you to discuss with your doctor before starting a course.

For its strengthening and densifying properties, we have decided to incorporate arginine into our mascara serum. This treatment also contains pea peptides, a sequence of amino acids known for their redensifying properties, and castor oil, a vegetable oil renowned for promoting hair and eyelash growth. These active ingredients work in synergy to nourish and provide resilience to the eyelashes. Formulated from 95% natural origin ingredients, the Typology mascara serum offers a natural effect while promoting a gradual lengthening of the lashes. Its light texture and its concentration in active ingredients allow it to stand out from traditional mascaras.

You can also find arginine in our resurfacing conditioner. Suitable for all hair types, even the most difficult to style, this silicone-free treatment helps to seal the cuticle scales to smooth the hair fibre and facilitate detangling. It also incorporates squalane, a natural emollient of squalene, known for its moisturising and protective virtues.

• UTAGAWA T. Production of arginine through fermentation. The Journal of Nutrition (2004).

• GAD M. Z. Anti-ageing effects of l-arginine. Journal of Advanced Research (2010).

• MESHRAM A. & SRIVASTAVA N. Diverse potential and pharmacological studies of arginine. Journal of Proteins and Proteomics (2015).

• WU G. & al. Safety and Efficacy of Arginine in Adults. The Journal of Nutrition (2016).

• SAHIN K. & al. Effects of a Combination of Arginine Silicate Inositol Complex and a Novel Form of Biotin on Hair and Nail Growth in a Rodent Model. Biological Trace Element Research (2023).