Astaxanthin, a substance in the
family, provides the pink color of salmon and many other sea creatures. Like other carotenoids, astaxanthin is a strong
. It has been advocated for treating or preventing a number of health conditions, but as yet none of these proposed uses is supported by meaningful scientific evidence.
Astaxanthin is not an essential nutrient. However, it is possible that increased intake of astaxanthin could provide health benefits.
Salmon is an excellent source of astaxanthin. A typical serving of Atlantic salmon provides approximately 1 mg of astaxanthin, while a similar serving of Pacific salmon might provide 4-5 mg.
is another good food source of astaxanthin.
When consistently exposed to high levels of ultraviolet light, the algae
produces very large quantities of astaxanthin, presumably to protect itself from injury. Haematococcus raised in this way is used as a commercial source of astaxanthin.
In studies, astaxanthin has been given in doses ranging from 4-16 mg daily.
Some evidence suggests that astaxanthin is better absorbed when consumed in an oily base.
Many health claims for astaxanthin are based on the fact that it is a strong antioxidant. However, in recent years, scientific confidence in the medical benefits of antioxidants has waned; study after gigantic study of antioxidants such as
have failed to find the hoped-for benefits.
Other proposed uses of astaxanthin have at least marginal supporting evidence from
. In one such study, 30 men with
were given either placebo or 16 mg of astaxanthin daily, for a period three months.
The results showed possible small benefits on laboratory measures of fertility.
Another study tested astaxanthin combined with the carotenoid
as a possible supplement for
enhancing recovery from exercise
. In this small trial, 20 body-builders were given either placebo or the carotenoid combination for three weeks.
Participants then engaged in intense exercise. The results failed to show that use of the astaxanthin/lutein combination reduced muscle soreness or signs of muscle injury.
Weak evidence additionally hints that astaxanthin might
reduce blood pressure
prevent heart disease
, protect the lens of the eye against
, protect the stomach against
, and reduce risk of
However, for none of these uses (or any other) can astaxanthin yet be remotely called a proven treatment.
Two studies failed to find astaxanthin significantly more effective than placebo for treating stomach irritation in people with
(nonspecific stomach pain).
As a widely consumed nutritional substance, astaxanthin is expected to have a low order of toxicity. In human studies, no serious adverse effects have been seen.
Maximum safe doses in pregnant or nursing women, young children, or individuals with severe liver or kidney disease have not been determined.