Astaxanthin is a powerful natural antioxidant and also has broad-spectrum anti-inflammatory properties (1-3).
Eye protection
Tso first described Astaxanthin’s (ASTA) ability to protect the eye from:-Light-induced damage- Photoreceptor cell damage- Ganglion cell damage- Neuronal damage - Inflammatory damage (4). Other scientists have found further benefits for the eyes when using ASTA. An extensive series of human clinical trials have shown that Natural Astaxanthin has positive benefits for both of the following conditions and their accompanying symptoms: Eye fatigue (“Asthenopia”) is becoming more prevalent due to extensive use of computers and other visual display terminals. This can manifest as eye strain, blurring and diplopia (when two images of a single object are seen because of unequal action of the eye muscles –double vision); Eye accommodation-the process by which the eye changes optical power to focus on a particular object as the viewing distance varies.
Eye strain and fatigue
In a randomized, double blind, placebo-controlled human clinical trial. After four weeks of supplementation with Astaxanthin, the authors reported a 46% reduction in the number of eye strain subjects. They also found higher accommodation amplitude (the adjustment in the lens of the eye that allows it to focus) in subjects who used visual display terminals (5,6) confirmed this observation. A double blind study evaluated Astaxanthin’s effect on eye fatigue as well as visual accommodation. Forty subjects were divided into placebo and treatment groups, with the treatment group receiving Astaxanthin for four weeks. Three separate visual parameters showed statistically significant benefits from Astaxanthin supplementation for eye fatigue and accommodation amplitude. (7). A study the following year corroborated these results concluding that taking Astaxanthin daily has the effects of reducing and preventing eye strain and accommodative dysfunction (8). This study showed both a prophylactic as well as a therapeutic potential for Astaxanthin for eye conditions such as fatigue and accommodation. In other words, besides being able to prevent eye strain and fatigue and improve accommodation. Astaxanthin also shows a capacity to reverse these conditions in people already afflicted with these disorders.
Astaxanthin’s preventative role was further displayed in a clinical study done on subjects whose eyes were healthy, with no signs of fatigue or strain. Both the treatment and the placebo groups in this study were subjected to heavy visual stimuli to induce eye fatigue, and it was found that the treatment group recovered more quickly. Hence, Astaxanthin may be useful not only to treat eye fatigue, but also to prevent eye fatigue from occurring in healthy people (9). Additional studies have shown that Astaxanthin supplementation for four weeks can reduce eye soreness, dryness, tiredness and blurred vision (10-12).
Visual function
20 year old, healthy men were randomly separated into a placebo group or a treatment group who were given Astaxanthin daily for four weeks. Statistically significant improvement was found in two different parameters—visual acuity (the ability to see fine detail) and depth perception. Depth perception in particular saw a remarkable improvement by 46% in the group supplementing with Natural Astaxanthin (13). Improvement in visual acuity has been found in an older group of subjects as well. This study took 49 healthy volunteers who were over the age of 40 and tested for improvements in visual function compared with a placebo. This study was done over a 28 day period, after which time the a statistically significant improvements in both visual acuity and accommodation time was observed in the “active” group. (6).
A human clinical study examined the ability of Astaxanthin to improve retinal capillary blood flow. Eighteen subjects were given Astaxanthin and another eighteen people were given a placebo. After four weeks it was found that the Astaxanthin group had improved retinal capillary blood flow as compared to the placebo group (14). A double-blind, placebo-controlled study separated healthy volunteers into a placebo group and a group that was given Astaxanthin per day for four weeks. The study examined Astaxanthin’s effect on blood flow to the vascular layer of the eye. Increased blood flow velocity was found in subjects taking Astaxanthin (15).
References
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2 Ohgami, K., Shiratori, K., Kotake, S., Nishida, T., Mizuki, N., Yazawa, K., Ohno, S. (2003). “Effects of astaxanthin on lipopolysaccharide-induced inflammation in vitro and in vivo.” Investigative Ophthalmology and Visual Science. 44(6):2694-701.
3 Lee, S., Bai, S., Lee, K., Namkoong, S., Na, H., Ha, K., Han, J., Yim, S., Chang, K., Kwon, Y., Lee, S., Kim, Y. (2003). “Astaxanthin Inhibits Nitric Oxide Production and Inflammatory Gene Expression by Suppressing IkB Kinase-dependent NFR-kB Activation.” Molecules and Cells. 16(1):97- 105.
4 Tso, M., Lam, T. (1996) “Method of Retarding and Ameliorating Central Nervous System and Eye Damage.” U.S. Patent #5527533.
5 Nagaki, Y., Hayasaka, S., Yamada, T., Hayasaka, Y., Sanada, M., Uonomi, T. (2002). “Effects of Astaxanthin on accommodation, critical flicker fusion, and pattern visual evoked potential in visual display terminal workers.” Journal of Traditional Medicines. 19(5):170–173.
6 Nakamura, et al. (2004). “Changes in Visual Function Following Peroral Astaxanthin.” Japanese Journal of Clinical Ophthalmology. 58(6):1051-1054.
7 Nitta, T., Ogami, K., Shiratori, K. (2005). “The effects of Astaxanthin on Accommodation and Asthenopia—Dose Finding Study in Healthy Volunteers.” Clinical Medicine. 21(5):543-556.
8 Iwasaki, T. and Tahara, A. (2006). “Effects of Astaxanthin on Eye Strain and Accommodative Dysfunction.” Journal of the Eye Vol. 23 No. 6 Page 829-834 (2006).
9 Takahashi, J., Kajita. (2005). “Effects of astaxanthin on accommodative recovery.” Journal of Clinical Therapeutics & Medicines. 21(4):431-436.
10 Nitta, T., Ogami, K., Shiratori, K. (2005). “The effects of Astaxanthin on Accommodation and Asthenopia—Dose Finding Study in Healthy Volunteers.” Clinical Medicine. 21(5):543-556.
11 Shiratori, K., Ogami, K., Nitta, T. (2005). “The effects of Astaxanthin on Accommodation and Asthenopia—Efficacy Identification Study in Healthy Volunteers.” Clinical Medicine. 21(6):637-650
12 Nagaki, et al. (2006). “The supplementation effect of astaxanthin on accommodation and asthenopia.” Journal of Clinical Therapeutics & Medicines. 22(1):41-54
13 Sawaki, K., Yoshigi, H., Aoki, K., Koikawa, N., Azumane, A., Kaneko, K., Yamaguchi, M. (2002). “Sports Performance Benefits from Taking Natural Astaxanthin Characterized by Visual Acuity and Muscle Fatigue Improvements in Humans.” Journal of Clinical Therapeutics & Medicines. 18:(9)73-88
14 Yasunori, N., et al. (2005). “The effect of astaxanthin on retinal capillary blood flow in normal volunteers.” J. Clin. Ther. Med. 21(5):537-542.
15 Saito, M., Yoshida, K., Saito, W., Fujiya, A., Ohgami, K., Kitaichi, N., Tsukahara, H., Ishida, S., Ohno, S. (2012). “Astaxanthin increased choroidal blood flow velocity.” Graefes Archive Clinical and Experimental Ophthalmology 2012 Feb;250(2):239-45.
