Astaxanthin to support tanning and provide a tanned complexion?

The astaxanthin has been mentioned as an active ingredient in the tanning process by stimulating melanin production. This idea stems from the red hue of this pigment. Astaxanthin also gives certain marine animals their pink color, including shrimp, crabs, and salmon. But can it enhance tanning in humans? As a reminder, melanin is a black or brown pigment produced during the melanogenesis, a process in which melanin is produced in melanosomes. For astaxanthin to promote tanning, it must activate melanogenesis. That does not seem to be the case.

Research in vitro has shown that astaxanthin reduces tyrosinase activity, a key enzyme in melanin synthesis. This mechanism involves inhibition of DOPA and dopaquinone auto-oxidation, two immediate melanin precursors. In a study on murine B16 melanoma cells, this inhibition resulted in a 40% reduction in melanin content, without detrimental effects on cell viability.

These observations were confirmed using a model based on human epidermal equivalents. When these tissues were stimulated for 14 days with a 5 nM stem cell growth factor, pigmentation developed. This correlated with increased expression of melanocyte-specific genes and proteins such as TYR, TYRP1, Pmel17, and MITF. Adding astaxanthin (1 to 8 µM) suppressed this growth factor–induced pigmentation in a dose-dependent manner without altering tissue structure. At 8 µM, inhibition was complete. Transcriptomic and proteomic analyses revealed that astaxanthin repressed expression of melanogenesis markers via the interruption of intracellular signaling associated with the growth factor. This suggests that this pigment exerts regulatory action upstream of melanogenesis.

Astaxanthin does not appear to facilitate tanning.

However, astaxanthin helps protect the skin from free radicals generated during sun exposure. It has notable antioxidant properties derived from its unique chemical structure. The 13 conjugated double bonds and polar end groups allow electron capture and insertion into membrane lipid bilayers, acting as a cellular shield. Moreover, studies in vitro have shown its ability to inhibit prostaglandin E2 release by HaCaT keratinocytes after UVB irradiation (20 mJ/cm2) or UVC (5 mJ/cm2), inflammatory mediators involved in sunburn onset.

However, it is important to note that astaxanthin should not be used as a substitute for adequate sun protection. It is not classified as a sunscreen filter and is not listed in Annex VI of Regulation (EC) No. 1223/2009 on cosmetic products. It remains essential to protect your skin from UV rays by using a sunscreen and by limiting sun exposure during the hottest hours of the day. Astaxanthin can complement UV filters and strengthen the skin’s defense against solar radiation.

Advice If you want a sun-kissed complexion without exposing your skin to UV rays, we recommend using a self-tanner. This type of product contains molecules that react with amino acids in the stratum corneum to form melanoidins (distinct from melanin), pigments that give skin a brown tint. Self-tanners offer a simple, safe way to achieve an even tint similar to a tan without sun exposure. Note that the color they impart fades over disappear completely within 5 to 7 days.