What should you know about the use of green algae in cosmetics?

In cosmetics, we typically use green algae of the type Chlorella. Appearing 2.5 billion years ago, these are freshwater micro-algae (lakes, ponds, and marshes), invisible to the naked eye. Their name comes from their very high concentration of chlorophyll compared to other micro-algae. Also known as the "green gem," green algae is prized by Asians for its nutritional and therapeutic properties, as it has significant nutritional capabilities due to its richness in plant proteins.

Since its discovery, a large number of studies have been conducted on chlorella, and it is currently being cultivated. The main varieties exploited are Chlorella vulgaris and Chlorella pyrenoidosa. At present, the majority of the crops are found in Asia, with a large portion of the global production coming from Japan and China. However, it is important to note that there are numerous "algae farms" in Europe that cultivate chlorella, notably in Germany, Spain, Portugal, and France.

The numerous benefits of green algae are made possible by the bioactive compounds they contain.

Note : The biochemical composition of green algae can vary depending on the cultivation method and extraction process.

Green algae can be used in topical applications or hair care, found in skincare products such as creams, masks, or serums. Due to its chlorophyll content, it can also be used in tinted cosmetic products. It offers various benefits for the skin and hair.

• Slowing down skin aging.

  Indeed, green algae could potentially slow down skin aging. By reducing the expression of matrix metalloproteinase-1 (MMP-1), which is responsible for collagen degradation, green algae could therefore improve skin elasticity.

  Furthermore, chlorella inhibits lipid peroxidation, thus preventing their degradation through resistance to oxidative stress. Free radicals are produced by this stress (pollution, tobacco, UV, etc.), which accelerates skin aging.

  The antioxidants found in chlorella, including carotenoids, astaxanthin, canthaxanthin, and flavoxanthin, will capture these free radicals by trapping single oxygen, which can prevent the damage caused by oxidation on the skin and slow down skin aging.

• Reducing vascular imperfections.

  Through the reduction of angiogenesis, green algae could potentially decrease the redness associated with dilated blood vessels (telangiectasias), as seen in conditions such as rosacea for example. It may also lead to the formation of a "sheath" of collagen around the dilated blood vessels to lessen their appearance and thus the associated redness.

  However, these results have only been demonstrated once. Further studies are necessary to confirm these hypotheses.

  Green algae can also promote the reduction of redness through the neutralization of the color red. Indeed, green algae is rich in chlorophyll, a green pigment. According to the color wheel, red and green are complementary colors, and when mixed, their hues cancel each other out. Green algae in green color correctors, for example, could "cancel out" the red color of redness.

• Promote and accelerate the healing process.

  The topical application of chlorella on lesions increases the number of fibroblasts, likely through the stimulation of the fibroblast growth factor (FGF), which in turn boosts the production of collagen fibers by the fibroblasts. This action facilitates the formation of connective tissue, enabling the wound to heal quickly and properly.

• Increasing skin hydration.

  Green algae in cream form can increase the skin's water content, allowing for better skin hydration. No mechanism has been determined yet. However, we can hypothesize that the omega-3s found in chlorella may contribute to this. They are essential for regulating skin lipids, such as ceramides, which keep the skin barrier healthy. Omega-3s promote the formation of a protective lipid barrier on the skin, which maintains hydration and increases its suppleness.

• Slowing down the appearance of white hair.

  No study has demonstrated any effect of green algae on hair. However, we can hypothesize that the antioxidant properties of green algae may play a role in hair health. Drying and stiffening of the hair fiber, related to lipid oxidation, are part of photo-aggravation (UV-related oxidation) of hair aging, according to studies. Hair proteins, like keratin, are photochemically protected by hair pigments.

  However, when pigments act to protect these proteins, they themselves can be degraded or discolored, resulting in white hair. It can be hypothesized that green algae, through its antioxidant effect and by preventing lipoperoxidation, can protect the hair from oxidative stress. It may help to preserve hair pigments by limiting or slowing the onset of white or gray hair.

These organisms are generally safe to use. However, due to the lack of scientific evidence on the subject, we cannot assert whether the application of green algae could pose problems. Nevertheless, their potential comedogenicity could raise concerns. Indeed, algae in general could present a risk of comedogenicity. They would penetrate the pores and accelerate the growth of micro-comedones.

However, this concept is debatable: no study has shown a comedogenic effect of green algae. Most green algae on the market are in the form of extracts, too small to "clog" pores; what is "comedogenic" for one person is not necessarily so for another, and the fact that an ingredient is "comedogenic" does not mean that the product containing it necessarily is.

To maximize the benefits of green algae, it is crucial to use it correctly. Ensure you strictly follow the usage instructions of skincare products containing green algae. Although its use generally poses no issues, you can perform a skin test by applying a product containing green algae in the crook of your elbow, on the inside of your wrist, or behind your ear to observe any potential skin reactions.

Do not hesitate to consult your doctor at the slightest doubt.

Suitable for all skin types, especially sensitive skin, our anti-redness corrector is a great ally for skin prone to localized redness. Upon application, its characteristic green color, combined with the presence ofgreen algae extract (INCI: Chlorella Vulgaris Extract), diminishes the appearance of redness by neutralizing red, according to the color wheel. This shade is light and natural, providing flexible coverage, without the need to apply foundation afterwards.

In the long run, the corrector reduces vascular imperfections : the green algae extract prevents the formation of new blood vessels and visibly diminishes the appearance of redness, while the niacinamide, present at 2%, soothes inflammations and restores the skin's membrane through the synthesis of intercellular lipids.

We recommend applying small dabs with the applicator to the red areas of the face, and using the tip of your finger or a brush to blend. This product can be easily removed with makeup remover oil or micellar water.

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• LEE W. S. Photoaggravation of hair aging. International Journal of Trichology (2009).

• VACA-GARCIA C. & al. Morphology, composition, production, processing and applications of Chlorella vulgaris: A review. Renewable and Sustainable Energy Reviews (2014).

• ACHMAD H. & al. Effect of the application of Chlorella vulgaris ointment to the number of fibroblast cells as an indicator of wound healing in the soft tissue of pig ears. Pesquisa Brasileira em Odontopediatria e Clínica Integrada (2020).

• MORADI A. M. & al. Effect of microalga Chlorella vulgaris extract compared to vitamin C on collagen І and MMP-1 genes expression in human skin fibroblast cells. Journal of Animal Environment (2020).

• NAYARANAN V. Holistic skin care and selection of skin care products in acne. Archives of Clinical & Experimental Dermatology (2020).

• RAYA I. & al. The effectiveness of Chlorella vulgaris cream applied to male and female rats. National Journal of Physiology, Pharmacy and Pharmacology (2020).