Many athletes put emphasis on training, fueling, and rest, but many do not focus on the importance of good eyesight. Optometrists estimate up to 80 percent of the information we accumulate during a sporting competition comes from our eyes and 95% of all physical movement is controlled visually and triggers the first movement of the athlete. (1,2,3) Even eye sight that is slightly blurred can reduce performance. (4)

EYE ANATOMY

The major components of the eye that affect performance and overall vision are the macula, retina and the lens.

Macula is an oval-shaped highly pigmented yellow spot near the center of the retina of the eye[t1]. It is responsible for central, high resolution/acuity vision. The macula is yellow in color and it absorbs excess blue and ultraviolet light that enter the eye, and acts as a natural sun block for the retina. [t2]

Retina is the layer at the back of the eyeball containing cells that is are sensitive to light and where a visual image is formed.[t3][t4]

Lens covers the front of the eye and its role (along with the cornea) is to focus light on the retina

NUTRITION

What types of foods you put in your body not only impacts performance but impacts your eyes. A large-scale research project conducted by the National Eye Institute found there are several nutrients that help protect our eyes. The most important ones are beta carotene, vitamin C, Vit D, Vit E, lutein, zeaxanthin, zinc and omega 3 fats (5).

Beta Carotene (Precursor to Vit A) is an antioxidant.—Helps produce pigment in the retina of the eye and promotes good vision especially in low light (night vision). Sources include apricots, broccoli, cantaloupe, carrots, dark green leafy vegetables, pink grapefruit, pumpkin, spinach, sweet potatoes.

Vit C— is a water soluble essential nutrient and an important antioxidant. The eyes need relatively high levels of high Vit C to function properly. One of its main roles is to support small blood vessels to and around the eyes. The lens of the eye is also highly concentrated with the nutrient(5). Sources include Brussels sprouts, bell peppers, broccoli, berries and citrus fruit.

Vit D (D3 cholecalciferol)—Has been shown to positivity impact vision and reduce retinal inflammation (6,). Food sources include cod liver oil, Atlantic pickled herring, salmon, mackerel , sardine and tuna packed in oil, fortified cereals/dairy/soy/tofu products, eggs and mushrooms.

Vit E (d-alpha tocopherol)— is one of our body’s most powerful fat soluble antioxidants. Higher intake of vitamin E can increase the level in the retina. Vitamin E is also found in the lens. It protects cells of the eyes from damage and provides ocular protection (5). Sources include wheat germ, almonds, sunflower seeds, hazelnuts, peanuts, peanut butter and sweet potatoes.

Lutein and Zeaxanthin—these powerful carotenoids are naturally present in the macula. They are part of the retina responsible for central vision. These vital nutrients work to filter 40-90% of the harmful blue light, the kind of light that can damage the macula. These nutrients act like sunscreen for your eyes. They can increase the pigment density in the macula. The greater the pigment density means better retina protection and a lower risk of macular degeneration (5). These antioxidants cannot be produced by our bodies on their own, so they must be obtained through diet and/or supplements. Sources include egg yolk, broccoli, corn, green leafy vegetables (kale, collards, spinach, turnip greens) and peas.

Zinc (Zinc Oxide)—is an essential mineral. It helps get vitamin A from the liver to the retina for eye-protective melanin production. Proper amounts of zinc help with ocular protection, night vision and cataract prevention. Sources includes fortified cereals, legumes of all kinds (black eyed peas, kidney beans, lima beans) lean red meat, poultry, seafood and pumpkin seeds.

Omega 3 Fatty Acids (Fish Oil)— two types — docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA.) They are major components of nervous and retinal tissues and are highly concentrated in the ocular tissues. They help promote healthy tear production necessary for healthy and comfortable eyes, protect tiny vessels within the eyes and low levels of these fatty acids can be linked to dry eye syndrome (7,8,9). Sources include salmon, tuna, sardines and anchovies.

Eye Health and Performance

The thicker and denser the macular pigment the more your eyes are protected. This thickness also reduces glare and light sensitivity along with improving photo stress recovery, contrast sensitivity, and processing speed (10). Since the eyes and brain are connected, a millisecond difference in seeing the ball for example is a difference between a strike and a home run. A 95-mile-per-hour fastball takes less than half a second to get to the plate. A player must decide to swing in approximately 0.458 seconds. That means the hitter must see the ball and decide whether to swing or not.

Eye Health for Macular Degeneration and Cataracts

Approximately 10% of people between 66 to 74 years of age will have findings of macular degeneration. The prevalence increases to 30% when they are between 75 to 85 years of age (11). Macular degeneration is when you have a loss of vision in the center of the visual field (the macula) because of damage to the retina. It is a major cause of blindness and visual impairment in older adults.

Cataracts are another common eye problem. By age 80, more than half of all Americans either have a cataract or have had cataract surgery. Cataracts are a medical condition in which the lens of the eye becomes progressively cloudy, resulting in blurred vision.

SUMMARY

Protecting your eyes and having optimal vision starts with the food on your plate. Maximizing the thickness of your macula pigment optimizes sports performance and decreases your chances of macular degeneration and cataracts. Aim for a diet high in green, leafy vegetables such as spinach, kale, and collards, salmon, tuna, and other oily fish, eggs, nuts, beans, other non-meat protein sources, and oranges and other citrus fruits or juices.

References

1. Arie B. Sports Vision: How enhancing your vision can give you that extra edge in competition. Peak Performance 2003;188:6-8.
2. Werner W. Contact lens fitting for sports. Contactologia 2000;22:92-4.
3. Spinell MR. Contact lenses for athletes. Optom Clin 1993;3:57-76.
4. Griffiths G.; Eye dominance in sport. Optometry Times:2003 43(16):34-40.
5. SanGiovanni JP, Chew EY, Clemons TE, et al; for Age-Related Eye Disease Study Research Group. The relationship of dietary carotenoid and vitamin A,E, and C intake with age-related macular degeneration in a case-control study: AREDS Report No. 22. Arch Ophthalmol. 2007;125(9): 1225-1232

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6. Lee.V, Rekhi.E, Hoh Kam.J, Jeffery.G. Vit D refuvenates ageing eyes by reducing inflammation, clearing amyloid beta and improving visual function. Neurobiolaging 2011; 33(10): 2382-2389.

7. Bonnielin. S, West.S Caulfield. L, Bressler.S, ,The Impact of Fish and Shellfish Consumption on Age Related Macular Degeneration. Opthalmology 117 (12): 2395-2401, December 2010

8. Sangiovanni JP, Agrón E, Meleth AD, Reed GF, Sperduto RD, Clemons TE, Chew EY. {omega}-3 Long-chain polyunsaturated fatty acid intake and 12-y incidence of neovascular age-related macular degeneration and central geographic atrophy: AREDS report 30, a prospective cohort study from the Age-Related Eye Disease Study. American Journal of Clinical Nutrition 2009 Dec;90(6):1601-7.

9. Chua B, Flood V, Rochtchina E, Wang JJ, Smith W, Mitchell P. Dietary fatty acids and the 5-year incident of age-related maculopathy. Arch Ophthalmol. 2006; 124(7): 981-98
10. Wooten BR, Hammond BR. Macular pigment: influences on visual acuity and visibility. Prog Retin Eye Res 2002 Mar;21(2): 225-40.
11. AgingEye Times (2009-05-19). “Macular Degeneration types and risk factors”. Agingeye.net. Retrieved 2011-01-11

[t1]Plagiarized from Wikipedia

[t2]Plagiarized from http://www.flashcardmachine.com/504-eyes.html

[t3]Plagiarized from

http://www.oxforddictionaries.com/us/definition/american_english/retina

[t4]These should be taken from an article or textbook and properly cited.