Benefits
Antioxidant support during hard training
In 32 elite young soccer players, 90 days of astaxanthin blunted the rise in superoxide after a hard exercise bout and gave lower post-exercise muscle enzyme levels than placebo, while other oxidative markers did not change. In 32 trained cyclists, 20 mg a day for 4 weeks raised blood astaxanthin but did not raise total antioxidant capacity, so the trials show mixed results.
Skin moisture and elasticity
A pooled analysis of nine small placebo-controlled trials found that oral astaxanthin improved skin moisture and elasticity, but wrinkle depth did not change significantly and results varied between trials. In one 16-week trial in 65 women, skin moisture and wrinkles worsened over autumn on placebo but held steady on 6 or 12 mg a day.
Cycling performance and fat use
In 12 recreational cyclists, 12 mg a day for 7 days cut 40 km time trial time by about 1.2% and raised late-race fat burning compared with placebo. A larger trial in 32 well-trained cyclists taking 20 mg a day for 4 weeks found no change in fat use or time trial performance.
Mechanism of action
Fat-soluble carotenoid
Astaxanthin is a fat-soluble carotenoid found in algae and other aquatic organisms. Taking it raises blood levels, but in trained cyclists this did not translate into higher total antioxidant capacity or lower lipid oxidation markers.
Calming UV-triggered skin signals (cell studies)
In cultured skin cells, astaxanthin reduced the inflammatory signals released by keratinocytes after UVB light and the collagen-degrading enzyme MMP-1 released by fibroblasts. In the matching human trial, the stratum corneum marker IL-1 alpha rose on placebo and the low dose but not the high dose.
Clinical trials
Randomized, placebo-controlled trial of 6 mg or 12 mg astaxanthin a day for 16 weeks, run in Japan from August to December; sponsored by an astaxanthin maker. (Tominaga et al. 2017, J Clin Biochem Nutr)
65 healthy women.
Wrinkle measures and skin moisture worsened significantly on placebo but did not change significantly with astaxanthin. Skin IL-1 alpha rose on placebo and the low dose but not the high dose. The UV protection findings came from cell studies, not from the volunteers.
Randomized, double-blind, placebo-controlled crossover trial of 12 mg astaxanthin a day for 7 days, with a 14-day washout. (Brown et al. 2021, J Sci Med Sport)
12 recreationally trained male cyclists.
Time trial time improved by 1.2% (about 51 seconds) with astaxanthin, and fat oxidation was higher in the final kilometre. A small, short trial.
Double-blind, placebo-controlled parallel trial of 20 mg astaxanthin a day for 4 weeks. (Res et al. 2013, Med Sci Sports Exerc)
32 well-trained male cyclists and triathletes.
Blood astaxanthin rose, but total antioxidant capacity, malondialdehyde, fat oxidation during exercise and time trial performance did not change compared with placebo.
Randomized, double-blind, placebo-controlled trial of astaxanthin for 90 days, followed by a 2-hour exercise bout. (Djordjevic et al. 2012, J Sports Med Phys Fitness)
32 elite young male soccer players.
After exercise, superoxide rose significantly only in the placebo group, and the muscle enzymes CK and AST were lower with astaxanthin. Lipid and protein oxidation markers did not change, and the antioxidant thiol gain was only marginally significant.