One of the main functions of astaxanthin is to counteract the unstable molecules that cause oxidative stress. One study looked at the impacts of astaxanthin on cognitive health in healthy middle aged and elderly adults who complained of age-related forgetfulness. Study participants received 6-12mg of astaxanthin daily and had positive changes in cognitive performance and memory (1).

Astaxanthin has been studied for its protective heart benefits in animal studies and human studies. In an animal study, astaxanthin was found to lower blood pressure in stroke-prone mice (1).

A study that looked at non obese subjects found that 6mg of astaxanthin daily could reduce triglyceride levels and increase HDL cholesterol, while showing no improvement in BMI or LDL cholesterol.(2).

During periods of heavy exercise training, muscle damage can lead to an over production of reactive oxygen species (ROS). The use of carotenoids with antioxidant properties may help to remove, deactivate and reduce the formation of ROS. Astaxanthin has only recently been studied as an ingredient that can support athletic performance. Animal studies have shown that supplementation in rats and mice with astaxanthin can reduce exercise induced muscle damage and delay exhaustion during exercise (1, 2).

Studies on athletes have shown that astaxanthin can reduce oxidative stress in humans. One study found that 4mg of astaxanthin increased positive responses to some oxidative stress markers when tested on soccer players (3). A trial done on competitive cyclists, showed an increase in power output for the group taking 4mg of astaxanthin (4).

Another study found that supplementing with astaxanthin improved strength endurance. Healthy paramedic students were split into two groups: one received 4mg of astaxanthin and one received a placebo. After 6 months, strength, endurance, and explosivity were measured in both groups. The astaxanthin group showed 3 times higher improvement in squatting than the placebo group (5).

As is the case in other body systems, carotenoids like astaxanthin help to neutralize the reactive oxygen species that can damage skin.

One study compared the benefits of vitamin c, vitamin E and astaxanthin, and found that astaxanthin had a significant impact on skin. The study assigned 66 subjects to three groups: group 1 was a placebo group; group 2 received astaxanthin, vitamin C, and vitamin E; and group 3 received vitamin C and vitamin E. The patient's skin was reviewed at 4 weeks, 8 weeks, 12 weeks and 20 weeks. Ocular inspection from skin photographs and 3 dimensional images of replicas and wrinkle values, measuring wrinkle areas and wrinkle volume rates revealed significant improvements in the astaxanthin group compared to the other groups. The group that received astaxanthin, vitamin C and vitamin E had significant improvements in wrinkle areas and volume compared to the other groups (1).

A study that looked at the impact of 6mg astaxanthin combined with ceramides had similar results. Study participants self reported changes in hair, skin and nail quality at 30, 60 and 90 days. In addition to self reporting, participants were also assessed by dermatologists who noted changes in skin quality. The results of the study indicate that supplementation with astaxanthin and ceramides improved globular folds, improved skin aging around the eyes, and reduced the severity of upper lip creases at Day 90 in study participants (2).

It is well established that carotenoids can support eye health.

One study looked at the impact of astaxanthin on responsiveness of the eyes and accommodation amplitude, which is the adjustment in the lens of the eye that allows it to focus. Study participants received 5mg of astaxanthin and reported a significantly larger accommodation amplitude than the control group at baseline. It was also noted that there was a 46% reduction in the number of eye strain subjects in the study group. The findings suggest that astaxanthin may help reduce the effects of screentime, such as temporary fatigue, eye strain and reduction in accommodation, on the eyes (1).

The role of astaxanthin in fatigue and eye strain related to computer use, was further displayed in a clinical study done on subjects whose eyes were healthy and were supplemented with 1mg of astaxanthin per day. Both the treatment group and placebo group were subjected to heavy visual stimuli to induce eye fatigue and the treatment group recovered more quickly. The results suggest that astaxanthin influenced recovery time (2).

In addition to supporting occasional eye fatigue and reduced accommodation associated with monitor use, astaxanthin has been shown to improve capillary flow of the retina. Subjects in a study who received 6mg of astaxanthin daily for four weeks had significantly higher retinal capillary flow, compared to the placebo group. Intraocular pressures in both groups remained unchanged during the supplementation period, meaning that astaxanthin increased retinal capillary perfusion without lowering intraocular pressure, a good sign that it is supporting healthy eye function (3).