health topics

Today, nearly 20% of Americans over 55 are affected by age related eye health issues. Around the world, there are some 30 to 50 million cases of blindness and even more people suffer visual impairment of some kinds. Two of the leading causes of visual impairment and blindness are age-related macular degeneration and age-related cataracts – both of which appear to be related to light-induced oxidative processes within the eye.

Cataracts develop from a variety of reasons, including long-term ultraviolet exposure, exposure to radiation, secondary effects of diseases such as diabetes, or simply due to advanced age; they are usually a result of denaturation of retinal lens proteins, which then clump together and cause cloudiness, resulting in blurred vision and potentially blindness. Macular degeneration (also known as AMD) occurs when the central portion of the retina (macula lutea) suffers thinning, atrophy, and in some cases bleeding. Non-genetic risk factors for AMD include smoking, hypertension, high cholesterol and high fat intake, exposure to sunlight and oxidative stress.

Both cataracts and AMD appear to be linked to the cumulative effects of a lifetime of light-induced oxidation. The use of antioxidants has been suggested as a method to reduce the risk of contracting both of these conditions. In particular, the more powerful antioxidants found in the carotenoid family of compounds have shown promise in clinical trials to reduce the risk of both nuclear cataracts and AMD. Studies have shown that lutein, zeaxanthin and astaxanthin all have positive effects on eye health in these areas.

One of the more interesting aspects of the compound astaxanthin is that it has been shown to cross the blood-brain and blood-retina barriers, meaning it can positively impact brain, central nervous system and eye health.