Astaxanthin antioxidant activity 550 x stronger than
Vitamin E?

Free radicals, such as peroxides and other forms of oxidative agents, like singlet oxygen, can:

• Cause severe damage to cells,
• Affect immune response mechanisms, and
• Have association with aging and a number of pathological conditions.

Biological antioxidants play a critical role in preventing oxidative damages to cell membranes and tissues.

Astaxanthin's ability to quench singlet oxygen has been consistently proven stronger than that of Vitamin E. Laboratory studies have:

• Demonstrated that astaxanthin efficacy in quenching singlet oxygen was up to 80 to 550 times higher than Vitamin E (Di Mascio et al. 1990, Shimidzu et al. 1996).
• Shown that astaxanthin could be up to 100 to 500 times more effective at preventing lipid peroxidation in animal membranes (Kurashige et al. 1990).

A wide variety of biological oxidation processes and oxidizing agents occur in nature. As a result, there is a vast array of methods to measure antioxidant activity. Each one is best adapted to a specific oxidation mechanism or oxidizing agent.

Also in some cases, their roles may be complementary.

• In the case of water-soluble antioxidants, such as vitamin C, where standardized assays, such as the ORAC-value test, have been developed, there is still a debate on their relevance.
• In the case of oil-soluble biological antioxidants, such as Vitamin E and astaxanthin, there are no such well accepted standardized tests, although most researchers agree to compare free radicals quenching rate constants in oxidation processes using the same oxidizing agents and substrates, as in the study mentioned above.

Other tests with different substrates and methodologies can lead to a different result. For example, Miki (1990) found that astaxanthin was only 15 fold more powerful than Vitamin E (alpha-tocopherol) at preventing lipid peroxidation, compared to 100 to 500 fold superior efficacy according to Kurashige et al. (1990), with different testing conditions.

Independent of those comparisons, because Vitamin E is an important vitamin for human health, with different properties from astaxanthin, it is advisable to follow recommendations for a daily intake of at least 40 IU of Vitamin E (as alpha-tocopherol), even when taking an astaxanthin supplement.

The vitamin-like properties of astaxanthin, which have been reported in some aquatic animals (but not in humans), derive in large part from its antioxidant properties. Interestingly, in fish, like salmon, astaxanthin has been shown to play a sparing effect on important antioxidant vitamins such as Vitamin E, C and A. This however, has not been fully studied in humans or mammals, although one study demonstrated that feeding astaxanthin to vitamin E-deficient rats, helped reduce the sensitivity of the membranes of their mitochondria and red blood cells to in-vitro oxidation.

References

For additional information, please visit www.astaxanthin.org.