The eye is the jewel of the body. Henry David Thoreau

Age-related macular degeneration (AMD) is characterized by a gradual loss of central vision generally in people over age 55. The macula is a small spot near the center of the retina which enables sharp central vision allowing us to see objects that are straight ahead. Unchecked the loss of central vision caused by AMD can impair driving reading discerning fine visual detail and other tasks that can interfere with employment independence and quality of life.

Similar to declines in other senses and functions a loss of visual acuity is a somewhat normal product of aging but AMD can be devastating when it begins in midlife and vision deteriorates steadily over time. With the aging of the Baby Boomer generation experts estimate there will be about 3 million cases of AMD in the U.S. by 2020. The condition affects females more than males (in part because females tend to have longer life spans). Race and eye color are additional non-modifiable risk factors with blue- or green-eyed Caucasians experiencing AMD more than African-Americans possibly due to lower amounts of melanin pigments or other protective factors in the iris and retina. Studies on twins indicate that there may be some degree of genetic susceptibility as well and family history of AMD is considered a risk factor.

However like so many conditions generally regarded as inevitable in the course of normal aging AMD is associated with modifiable diet and lifestyle risk factors which suggests it might be preventable or at least slowed in progression with targeted nutritional and lifestyle strategies. AMD is associated with some of the conditions related to the metabolic syndrome and systemic inflammation such as hypertension obesity diabetes coronary artery disease history of stroke and elevated homocysteine and high-sensitivity CRP. This is not surprising considering the ocular complications that accompany unmanaged diabetes. Other modifiable risk factors include smoking and physical inactivity.

The good news is the same dietary and lifestyle changes that can improve the aforementioned conditions can also have positive impacts on eye health and AMD. It shouldn't surprise us that what's good for the rest of the body is good for the eyes. Lifestyle recommendations include quitting smoking and increasing physical activity. A systematic review established a strong association between smoking and AMD with 13 of 17 studies showing current smokers to have a two-to-three-fold increase in risk for AMD compared to those who never smoked. Some of the chosen studies showed a dose-response effect and a temporal relationship with reversibility of the disease suggesting that one could potentially undo some of the damage by quitting smoking as soon as possible.

Another lifestyle intervention is wearing sunglasses and possibly the amber goggles designed to block blue light. Long-term exposure to shortwave radiation and blue light has been demonstrated to have a negative impact on photoreceptors and retinal pigment epithelial cells leading to photochemical damage and cell death.

Nutritional strategies include increasing intake of omega-3 fats and decreasing consumption of omega-6s. Intake of omega-3 fats is inversely associated with AMD. Regarding carbohydrates increased intake of high-glycemic carbs is associated with an elevated risk for AMD which fits with the retinal damage induced by long-term elevations in blood glucose. An effective and delicious dietary step to combat AMD is increasing consumption of antioxidants and carotenoids particularly the ones associated with eye health such as lycopene lutein and zeaxanthin. Since these carotenoids are fat-soluble and are more effectively absorbed and assimilated when eaten with fat AMD is one case where great flavor might benefit health perhaps in the form of fresh tomatoes with olive oil or a pat of butter on a sweet potato. The sulfur compounds in cruciferous vegetables also have protective effects for retinal tissue and with egg yolks being a good source of lutein it seems a veggie omelet with broccoli kale tomatoes and orange peppers can be aptly thought of as “eye food.

For more information on nutrition and aging please listen to our Clinical Rounds call from April 11 2012 Regenerative Medicine -The Real Cause of Aging and How to Reverse it with Edwin Lee MD.