Egg Nutrition Center Blog

Save Your Sight: Keep an Eye on Your Diet


N-Cochran-torsoToday’s post comes from Neva Cochran, MS, RDN, LD. Cochran is a nutrition communications consultant, appearing regularly in national and local media to discuss nutrition topics. Cochran is a long-standing nutrition contributor for Woman’s World Magazine, as well as a member of ENC’s Health Professional Advisory panel.

No doubt everyone has heard since childhood that carrots are good for the eyes. And carrots are an excellent source of beta-carotene, a phytonutrient that is converted into vitamin A in the body. Vitamin A promotes eye health, particularly helping to prevent night blindness, or the inability to see clearly when going from bright to dim light. According to recent research, however, there are several other nutrients that can reduce the risk of vision problems associated with aging, like cataracts and age-related macular degeneration (AMD).

Lutein and Zeaxanthin
Lutein and zeaxanthin are powerful antioxidants that protect the macula, a spot near the center of the retina of the eye, from free radical damage. High dietary intakes of lutein and zeaxanthin can reduce the risk of cataracts by up to 20% and macular degeneration by up to 40% (1). Lutein and zeaxanthin are found in egg yolks as well as dark green and orange fruits and vegetables like spinach, broccoli, turnip greens, peas, corn, squash, melon, nectarines, oranges, papaya, guava and bell pepper. The lutein and zeaxanthin in eggs may be more bioavailable than that in fruits or vegetables because eggs contain fat, which enhances absorption of these fat-soluble compounds. Indeed, research has demonstrated that eating one egg a day increases blood lutein and zeaxanthin levels (2, 3).

Vitamins A, C, E and Zinc
As antioxidants, vitamins A (beta carotene), C and E protect the lens of the eye from free radical damage, while zinc is required for the production of melanin, a pigment that helps protect the eye. In the Rotterdam study, Dutch researchers found a diet with foods high in beta-carotene, vitamins C, E and zinc was linked with a 35% reduced risk of AMD (4, 5). Milk, yogurt, eggs and some breakfast cereals provide vitamin A, and in the form of beta-carotene, sources are dark green and orange fruits and vegetables. Vitamin C is plentiful in citrus fruit, strawberries, kiwi, cantaloupe, bell pepper, broccoli and potatoes, while beef, pork, oysters, fortified cereals, milk and eggs supply zinc.

The Women’s Health Study showed that participants who consumed the most vitamin E were 14% less likely to develop cataracts (6). Vitamin E-rich foods include vegetable oils, nuts, sunflower seeds, wheat germ and sweet potato.

Omega-3 Fatty Acids
Evidence suggests that inflammation plays a role in AMD, and omega-3 fatty acids may help regulate inflammatory and immune responses in the retina to reduce risk. Omega-3s are most plentiful in deep water fish like salmon, mackerel, tuna, herring and sardines, while soybean and canola oil, flaxseed and walnuts provide a plant form of these fats. Eating fish just once a week reduced early AMD by 40% in a group of over 3500 subjects (7). Other studies have also confirmed omega-3s’ protective effect against AMD (4, 8).

The bottom line: eating a variety of nutrient-rich foods with plenty of colorful fruits and vegetables, lean meats, low-fat dairy, eggs, whole grains and healthy oils will help promote good vision and protect against age-related vision conditions.

Neva Cochran, MS, RDN, LD

 

References:

  1. Moeller SM, Jacques PF, Blumberg JB. The potential role of dietary xanthophylls in cataract and age-related macular degeneration. J Am Coll Nutr 2000; 19: 522S-527S.
  2. Goodrow EF, Wilson TA, Houde SC, Vishwanathan R, Scollin PA, Handelman G, Nicolosi RJ. Consumption of one egg per day increases serum lutein and zeaxanthin concentrations in older adults without altering serum lipid and lipoprotein cholesterol concentrations. J Nutr 2006; 136: 2519-2524.
  3. Ata S, Barona J, Kopec R, Jones J, Calle M, Schwartz S, Luz Fernandez M. Consumption of either one egg or lutein-enriched egg per day increases HDL cholesterol, reduces apolipoprotein B while increasing plasma carotenoids and macular pigment density in adult subjects. FASEB J 2010; 24: 92.4
  4. Ho, L et al. Reducing the Genetic Risk of Age-Related Macular Degeneration With Dietary Antioxidants, Zinc, and Omega-3 Fatty Acids. Arch Ophthalmol 2011; 129:758-766.
  5. van Leeuwen R, Boekhoorn S, Vingerling JR, Witteman JC, Klaver CC, Hofman A, de Jong PT. Dietary Intake of Antioxidants and Risk of Age-Related Macular Degeneration. JAMA 2005: 294:3101-3107.
  6. Christen, W, Liu, S, Glynn, R, Gaziano, J, Buring, J. Dietary Carotenoids, Vitamins C and E, and Risk of Cataract in Women. Arch Ophthalmol. 2008; 126:102-109.
  7. Chua, B et al. Dietary Fatty Acids and the 5-Year Incidence of Age-Related Maculopathy. Arch Ophthalmol. 2006; 124:981-986.
  8. Seddon J, George, S, Rosner B. Cigarette Smoking, Fish Consumption, Omega-3Fatty Acid Intake, and Associations With Age-Related Macular Degeneration. Arch Ophthalmol. 2006; 124:995-1001.

Author: Guest Blogger