A healthy diet is not only good for the body, but also good for the eyes. Caring for the eyes and preventing major visual disorders can be as easy as eating fruits and vegetables and avoiding certain risk factors. Disorders to the eyes—i.e., cataracts, age-related macular degeneration (AMD), dry eye-syndrome (DES), and glaucoma—cost Americans over 40 years of age about $36 billion annually. AMD is the leading cause of blindness in people 55 and older, and 10 million Americans suffer from DES. Prevention and protection are the keys to preserving vision for a lifetime.
Vision involves many processes and all the parts within the eye and the brain. Protecting the eyes from free radical damage and supporting healthy blood vessels and circulation are keys to good eye health. The every day factors that contribute to poor eye health are sun, pollution, genetic factors, smoking, a high body mass index (BMI), alcohol intake and poor nutrient intake. All of these factors (except genetics) are creators of free radicals. Free radical damage occurs throughout the body including the cells in the eyes. Free radicals can contribute to the onset of vision problems such as cataracts and glaucoma; research has shown susceptibility to AMD may be predominately genetic, however, the factors listed above can make it worse. Damage to the delicate retinal tissue is permanent and cumulative over one’s lifetime. These tissues in the retina are vulnerable to damage because they are made up of polyunsaturated fatty acids such as docosahexaenoic acid (DHA). These fatty acids are unstable structures that can be easily damaged when exposed to free radicals. Therefore, wearing sunglasses, avoiding cigarette smoke and pollution, staying fit and controlling weight, limiting alcohol intake, and eating a healthy diet are all great preventive measures for eye health.
A healthy diet provides benefits for overall health as well as eye health. Eating foods that contain antioxidants and essential fatty acids (EFAs) is the place to start. These two ingredients together pack a powerful punch when it comes to preserving eye health. There are numerous food sources for antioxidants, including citrus fruits and vegetables for vitamin C, nuts and seeds for vitamin E, carrots and sweet potatoes for beta-carotene, egg yolks for vitamin A, and dark green leafy vegetables for the carotenoids lutein and zeaxanthin. Eating blueberries and/or black currants, high in antioxidants, has also been associated with the reduction of eye fatigue.1 Eating fish and taking fish oil are the best sources of EFAs in the diet. Research has shown weekly consumption of fish is linked to a lower risk of early AMD.2 In addition, studies have shown those consuming higher amounts of fish had a 68-percent reduced risk of DES.3 The Age-Related Eye Disease Study (AREDS), sponsored by the National Eye Institute found taking high levels of vitamin C, vitamin E, beta-carotene and zinc can reduce the risk of developing AMD by about 25 percent.4 Today, the formula designed from this study is widely used by patients with any stage of AMD.
From this research, it is evident a diet rich in antioxidants and fish oils is important for eye health. Those who do not eat these foods on a daily basis should consider supplementation. Taking vitamin C, vitamin E, lipoic acid, N-acetyl cysteine and other antioxidants can protect cells from free radical damage. Supplementing with lutein and zeaxanthin can help protect the retina from damaging exposure from sunlight, shielding up to 40 percent of damaging ultraviolet (UV) rays to help maintain ocular health.5
DHA from fish oil accounts for approximately 30 to 35 percent of the total fatty acids found within the eye. DHA is vital for the development, function and maintenance of the ocular cells. DHA deficiencies have been associated with changes in visual development, reduced vision and impaired visual evoked potential.