Astaxanthin belongs to a group of compounds called carotenoids. While b-carotene is a vitamin A precursor, astaxanthin cannot be converted to vitamin A. In laboratory studies, astaxanthin has been reported to be typically at least 10 times more potent as an antioxidant than the other standard carotenoids such as canthaxanthin, b-carotene, lutein, lycopene, tunaxanthin and zeaxanthin. Astaxanthin provides the rich pink color observed in various aquatic species including salmon, crabs, lobster, shrimp and even some nonaquatic species such as the flamingo (whose diet includes some astaxanthin-producing organisms).
Oxidative stress is caused when there is increased oxidant production in animal cells characterized by the release of free radicals resulting in cellular damage. In humans, oxidative stress is involved in many diseases, such as cancer, Parkinson’s disease, heart failure, Alzheimer’s disease, and chronic fatigue syndrome, but short-term oxidative stress may also be important in the prevention of aging.
A recent study published in Phytotherapy Research examined the effect of astaxanthin supplementation in overweight and obese adults. The study included 23 adults with BMI of greater than 25 who were randomly assigned to receive either 5 mg or 20 mg of astaxanthin daily for three weeks. Oxidative stress biomarkers were measured at baseline and then again 1, 2 and 3 weeks after astaxanthin supplementation. At the end of the study, it was found that both groups saw marked increases in levels of the body’s own antioxidant defenses, as well as significant decreases in biomarkers of oxidative stress. Although plasma concentrations of astaxanthin were higher in the group receiving 20 mg per day, there were no significant differences in levels of biomarkers between the two groups. These findings suggest that 5 mg of astaxanthin may provide beneficial protection against oxidative stress in overweight and obese adults.