Astaxanthin crosses the blood brain barrier to reach the eyes
A leading cause of blindness, age-related macular degeneration, is a progressive disorder affecting the central part of the retina, called the macula. There is mounting evidence that two carotenoids – lutein and zeaxanthin – have a direct role in altering the course of this disease. These two are major carotenoids in the macular, and the macular pigment protects against light-induced damage to the retina, as well as macular degeneration. These carotenoids also protect the eyes from UV-induced free-radical damage.
Interestingly, the structure of astaxanthin is very similar to that of lutein and zeaxanthin, and it may have even stronger antioxidant activity than those carotenoids in terms of protecting against UV-light.1
Astaxanthin is capable of crossing the blood-brain barrier and is documented to deposit in the retina of mammals. Animal research shows that retinal photoreceptors of animals supplemented with astaxanthin sustain less damage from UV-light and recover more quickly than animals not supplemented with this carotenoid. This protection of the retina is accomplished, in part, by averting degeneration of photoreceptors in the eye.
Italian researchers completed a very positive human clinical trial of astaxanthin for treatment of age-related macular degeneration.2 In this study, 27 patients with this vision problem either received no supplements or a combination of 4 mg of astaxanthin with other vision-supportive supplements (vitamin C, vitamin E, zinc, copper, lutein and zeaxanthin). This supplement cocktail was continued daily for 12 months. This supplement regimen was found to improve function in the central retina.
Cataracts are another significant cause of blindness and impaired vision in older adults. Factors that delay or prevent cataracts would greatly benefit the quality of life for many seniors. Nutrition researchers have eyed antioxidants for a while when it comes to cataracts, since free radicals are a major culprit in the formation of cataracts.
A study involving athletes (handball players) showed that taking astaxanthin improves visual acuity, especially for depth perception.3 Another human trial, this time based on office workers who used a computer terminal all day, found that supplementing with astaxanthin led to improved visual acuity.4
O’Connor I, et al. Modulation of UVA light-induced oxidative stress by beta-carotene, lutein and astaxanthin in cultured fibroblasts. J Dermatol Sci 1998;16:226-230.
Parisi V, et al. Carotenoids and antioxidants in age-related maculopathy Italian study: multifocal electroretinogram modifications after 1 year. Ophthalmology 2008;115(2):324-33.
Sawaki K, et al. Effect of astaxanthin on sports performance: effect on visual function and muscle fatigue recovery in athletes. J Clin Ther Med 2002;18:1085-99.
Nakamura A, et al. Change in visual function from astaxanthin. Jpn J Clin Ophthalmol 2004;58:1051-4.