Red cells of the microalga Haematococcus pluvialis under the microscope, a source of astaxanthin

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Strong evidence22 studies

How we rate

“Strong” = several concordant meta-analyses or systematic reviews. “Moderate” = one synthesis, or several controlled trials. “Limited” = early trials only. The rating is about the quality of the studies, not about how useful the supplement is.

Astaxanthin

Red pigment from a microalgae: a few encouraging trials on cycling and skin, but the largest meta-analysis (24 trials) finds no performance gain, only slightly less creatine kinase after exercise.

Recovery

Benefits

Slightly reduces a marker of muscle damage after exercise: lower creatine kinase in a meta-analysis of 24 trials (effect size of −0.45), and in 32 elite young football players after 90 days of supplementation
Yields a 1.2% gain (51 seconds) on a 40 km time trial after 7 days at 12 mg per day, in 12 trained cyclists; and 121 seconds over 20 km after 28 days at 4 mg per day, in 7 competitive cyclists
With regular training, improves physical performance and fat utilization in a meta-analysis of 11 trials (346 participants), especially starting from 20 mg per day and beyond 12 weeks
Makes the skin more hydrated and more elastic: meta-analysis of 9 oral trials, with no significant effect on wrinkle depth
Increases HDL cholesterol by 1.5 mg/dL on average (meta-analysis of 14 articles); CRP only decreases after at least 12 weeks or above 12 mg per day
Lowers oxidative stress markers in heavy smokers (5 to 40 mg per day for 3 weeks) and in overweight adults (12 weeks)

Precautions

At 6 mg per day for 8 weeks, a safety trial on 35 healthy adults finds no clinically significant adverse effects, and no adverse effects were observed in 96 people at 6 or 12 mg per day for 12 weeks; the studies in this file say nothing about safety beyond these doses and durations. The largest meta-analysis (24 trials, 2026) finds no gain in VO2max, time trial performance or power: the two positive trials on cycling involve 12 and 14 cyclists, and a third, at 20 mg per day, sees nothing. On blood lipids, a meta-analysis of 7 trials (280 participants) finds no effect on cholesterol, triglycerides or blood glucose, and another nothing on body weight or blood pressure. On exercise-induced oxidative stress, a meta-analysis from 2026 finds only a decrease in a protein marker, nothing on other markers or muscle damage. In kidney transplant recipients, 12 mg per day for 12 months changed nothing regarding arterial stiffness, oxidative stress or inflammation.

Recommended dosage

4 to 12 mg per day in most trials, for 1 to 12 weeks

How to take it

For cycling: 4 mg per day for 28 days, or 12 mg per day for 7 days, in the two positive trials; 20 mg per day for 4 weeks changed nothing in well-trained cyclists.
For skin: 4 mg per day for 10 weeks in the UV trial (23 healthy individuals).
For blood lipids: 6 to 18 mg per day for 12 weeks; the decrease in CRP only appears after at least 12 weeks or above 12 mg per day.
For memory: 6 or 12 mg per day for 12 weeks in 96 middle-aged or elderly people complaining of forgetfulness; the authors consider the sample too small to conclude.
Form: several trials use an extract of the microalgae Haematococcus pluvialis rich in astaxanthin, in capsule form.
What does not work: 4 mg per day for 3 weeks reduced neither muscle soreness nor muscle damage after eccentric exercise in strength-trained men.

Did you know?

In a small trial, 28 mg of astaxanthin per day for only 4 days prolonged cycling exercise to exhaustion from 72 to 85 minutes in 10 active young men — a gain that the meta-analysis of 24 trials does not find on average.

What the studies say

This meta-analysis of randomized controlled trials in humans showed that astaxanthin supplementation significantly reduced advanced oxidation protein products (AOPP), which suggests a decrease in oxidative stress at the protein level. However, it did not reveal significant changes for other biomarkers related to oxidation or muscle injury.
You T, Peng K, Zhao K, Liu S, Sun F, Yu B, Dou Y, Tang J, Jiang W, Liu C. — 3 Biotech (2026) — View the source study

For information only: not a substitute for medical advice. Dietary supplements are not a replacement for a varied, balanced diet. Learn more