Beyond its cosmetic use, astaxanthin can also be consumed, in the form of capsules or gummies for instance. When taken orally, astaxanthin is believed to act more globally on the body, neutralising free radicals in tissues and cell membranes. It is also thought to have beneficial effects on the skin: this pigment could enhance skin hydration and reduce the appearance of wrinkles. Astaxanthin-based dietary supplements are also credited with a positive impact on the immune system, athletic performance, and fatigue.
Whether consumed in capsules or gummies, astaxanthin is currently viewed as a versatile active ingredient, bridging the gap between nutraceuticals and dermo-nutrition.
Several clinical trials have explored the impact of astaxanthin supplementation on skin quality. The doses generally studied range between 3 and 6 mg per day. This dosage appears to be sufficient for the active ingredient to exert its antioxidant effects, particularly on skin structural alterations related to UV rays. A randomised double-blind placebo-controlled Japanese study, published in 2018, evaluated the effects of a daily supplementation of 4 mg of natural astaxanthin for 10 weeks. The 23 participants, all in good health, then had their skin exposed to UV to measure the minimal erythemal dose, an indicator of sun sensitivity. The group that received astaxanthin showed an increase in the UV reaction threshold, indicating a better protection against sunburn. In addition, transepidermal water loss in the irradiated areas was significantly reduced, suggesting a better maintenance of skin hydration. Participants also noted a subjective improvement in the roughness and texture of their skin.
Even though astaxanthin can enhance the skin's protection against the sun, it cannot replace a sunscreen.
These findings align with a review of scientific literature published in 2021, which lists several clinical studies, including six randomised placebo-controlled trials. It highlights a significant improvement in the appearance of wrinkles, skin texture, and hydration levels after a few weeks of supplementation. Astaxanthin could potentially provide support against photoaging of the skin. Furthermore, no adverse effects have been reported to date following oral intake of astaxanthin at doses between 3 and 6 mg, although it should be noted that studies are often limited by their modest size.