Microalgae are organisms found in marine or freshwater environments. They are considered photosynthetic organisms: in other words, they use light sun and CO2 from the environment to produce their “food”. In fact, for their metabolic properties, microalgae could be considered a rich source of proteins, lipids, carbohydrates, vitamins, and minerals. Therefore, these organisms have been used as "superfoods" 1. But, besides being a superfood, microalgae are rich in essential healthy fatty acids (omega 3) and high-value antioxidants such as carotenoids2. These latter are an important aid to fight oxidative stress and are very beneficial for skin, eyesight and cellular health 3,4.
Among all the carotenoids found in microalgae, astaxanthin is a peculiar carotenoid-pigment with a deep red color biosynthesized by Haematococcus pluvialis5. Astaxanthin is responsible for the red pigmentation of animals such as flamingos, prawns, salmons, and trouts because all of them have a high intake of H. pluvialis microalgae containing Astaxanthin 3.
The accumulation of astaxanthin in the microalgae H. pluvialis is a very interesting process. In normal and suitable conditions, the microalgae stay in a green or vegetative phase; however, as soon as they are exposed to harsh conditions (UV-light, nutrient inhibition or high salinity), they start to produce astaxanthin, thus becoming red, as a way to protect themselves from the environmental stress2.
But why does H. pluvialis produce astaxanthin to protect itself? Well, astaxanthin is considered to have a potent antioxidant effect that neutralize the free radical action on cells, preventing diseases and aging. The unique structure of astaxanthin allows it to cross biological membranes and tissues to reduce and stabilize free radicals4.
The combination of the high antioxidant power and the anti-inflammatory properties of astaxanthin improve gastrointestinal health, can prevent and fight age-related neurodegenerative illnesses such as Alzheimer’s or Parkinson’s disease, other liver, eye or joint pathologies and also prevent or inhibit cancer cell growth in tissues (breast, colon, prostate)4.
It seems astaxanthin prevents and fights many diseases, right? Just wait until you know how it works for skin health. It is well known that sun exposure, and thus UV-light exposure, induces skin damages like DNA alterations, collagen reduction (aging) and melanin production (dark skin spots)6–8. And yes! You are right! Astaxanthin has been reported to help fight all of these skin problems.
In fact, an in vitro assay (culture of human cells in artificial conditions) was performed to evaluate a natural astaxanthin algal extract potential as cell protection against UV-A. This radiation is the major contributor to malignant melanoma formation in the skin dermis because of its ability to penetrate more deeply into it. In the study, astaxanthin showed a protective effect by reducing DNA damage and promoting the cellular antioxidant status maintenance (up-regulation of skin antioxidant defense enzymes) 8.
Other studies evaluated the topical treatment and the oral supplementation of astaxanthin to assess its effects on UV-induced skin damage. One of them concludes that the topical application of astaxanthin inhibits the reduction of collagen (Figure 2) and reduces hyperpigmentation of dark spots by preventing melanin production. In addition, the combination of both topical treatment and oral supplementation can improve skin condition, elasticity and luminosity in all layers (stratum corneum, epidermis, and dermis) 6,7.
After all this information, I am certain that you are thinking of how to incorporate astaxanthin in your skincare routine. The easiest way to incorporate it is through cosmetics as serums or creams with astaxanthin extract, but you can always complement your skincare routine with vitamin-based oral supplements, especially because astaxanthin, in general, is an ally against oxidative stress for your entire body3
References
1. Gould, W. The Klog. The Benefits Algae Bring To Your Skin (2016). Available at: https://theklog.co/algae-benefits-skin-care/. (Accessed: 7th November 2019)
2. Shah, M. M. R., Liang, Y., Cheng, J. J. & Daroch, M. Astaxanthin-Producing Green Microalga Haematococcus pluvialis: From Single Cell to High Value Commercial Products. Front. Plant Sci. 7, (2016).
3. Ambati, R. R., Moi, P. S., Ravi, S. & Aswathanarayana, R. G. Astaxanthin: Sources, extraction, stability, biological activities and its commercial applications - A review. Mar. Drugs 12, 128–152 (2014).
4. Guerin, M., Huntley, M. E. & Olaizola, M. Haematococcus astaxanthin: Applications for human health and nutrition. Trends Biotechnol. 21, 210–216 (2003).
5. Goedeke, R. Astaxanthin. Biosphere Nutrition Available at: https://www.biospherenutrition.co.nz/astaxanthin. (Accessed: 19th November 2019)
6. Hama, S. et al. Protective Effects of Topical Application of a Poorly Soluble Antioxidant Astaxanthin Liposomal Formulation on Ultraviolet-Induced Skin Damage. J. Pharm. Sci. 101, 2909–2916 (2012).
7. Tominaga, K., Hongo, N., Karato, M. & Yamashita, E. Cosmetic benefits of astaxanthin on humans subjects *. Acta ABP Biochim. Pol. 59, 43–47 (2012).
8. Lyons, N. M. & O’Brien, N. M. Modulatory effects of an algal extract containing astaxanthin on UVA-irradiated cells in culture. J. Dermatol. Sci. 30, 73–84 (2002).
9. Olayon, N. & Vaughn, A. LearnSkin. Astaxanthin is a Super Antioxidant for Your Skin Available at: https://www.learnskin.com/articles/astaxanthin-is-a-super-antioxidant-for-your-skin. (Accessed: 10th November 2019)
Such a good article! Imagine a skin care line with astaxanthin adressed to young adults who have started showing aging signs because of stress and screens.