Nutritional Support for Eye Health

This is part of our ongoing The Best Kept Secrets to Healthy Aging spotlight. Each week, we will be posting some of the great information that’s packed into our book, The Best Kept Secrets to Healthy Aging.

Today’s topic:
Eye Health – Seeing is Believing

Vision and eyesight often receive little attention when it comes to nutrition. The vast majority of people are unaware that there are foods and nutritional support ingredients that can promote healthy vision as they get older. Whether you prefer to add selected fruits and vegetables to your diet, supplement your diet with an appropriate high-quality formula, or both, the foundation of eye health is the combination of several ingredients that prevent free radical destruction of eye tissue over the long run to maintain healthy visual function with age. These include basic antioxidants such as vitamins C and E, ß-carotene, and the mineral zinc (balanced with copper); two vastly underappreciated phytonutrients – lutein and zeaxanthin; the extract of French maritime pine bark – Pycnogenol – and potentially the structural-support nutrient hyaluronic acid. These powerful nutritional support champions form the basis of every healthy vision regimen.

Antioxidants ß-Carotene, vitamins C, E and Zinc

The AREDS (Age-Related Eye Disease Study) trial was conducted several years ago under the sponsorship of the National Eye Institute, which is a part of the National Institutes of Health. The trial was conducted to evaluate the effect of supplementation with antioxidant vitamins and the mineral zinc in supporting eye health in aging individuals. The AREDS study involved 4,757 participants aged between 55 and 80 years old. The results of the study were released in October 2001. The study participants supplemented with either antioxidants alone, zinc alone, or the combination of antioxidants plus zinc for an average of 6.3 years. The group supplementing with the combination had the best outcomes with statistically significant results in maintaining normal visual acuity over that period of time.1

The formula used in the study included 500 mg of vitamin C, 400 IU of vitamin E, 15 mg of ß-carotene, 80 mg of zinc and 2 mg of copper supplemented on a daily basis. This study was integral in showing that a relatively high dose of antioxidant nutrients was able to help promote healthy vision in elderly individuals, and suggests the benefits of antioxidant supplementation to eye health.

The human retina contains the photoreceptor cells that convert light into vision. A healthy retina is absolutely vital to good vision. Oxidative damage to the eye is the most common cause of vision problems and loss in adulthood.2 Preventing oxidative damage before it happens is the best protection you can give your eyes.

Lutein, Zeaxanthin and the Retina

Fortunately, the retina contains lutein and zeaxanthin, the carotenoid cousins of ß-carotene. Lutein and zeaxanthin absorb ultraviolet light – a powerful antioxidant effect that protects the retina from oxidative damage. The absorption of ultraviolet light before it reaches the photoreceptors also helps to keep the visual image clear and distortion-free. By absorbing ultraviolet light, lutein and zeaxanthin contribute to visual acuity.

Smoke in Your Eyes (a bad thing)

Smoking has detrimental effects all around. Several tissues can suffer oxidative damage as a result of exposure to several of the compounds present in cigarette smoke. Direct exposure to cigarette smoke causes oxidation in the eye and its internal structures, and can double the retina’s need for the carotenoids lutein and zeaxanthin.

Age-Related Changes in Vision

Age also increases the retinal requirement for lutein and zeaxanthin, which approximately doubles between the ages of 20 and 80 years.3 Elderly men and women with low amounts of retinal lutein and zeaxanthin experience a decline in visual acuity and are much more likely to suffer age-related visual stress. Daily dietary supplementation with as little as 6 mg of lutein is a powerful promoter of visual acuity and eye health.4,5

Of course, “age-related” refers less to the fact that an individual is getting older and more to the fact that there is oxidative damage to eye tissue, which can occur at any age and in any individual. Thus, ensuring adequate lutein intake can be beneficial for everyone.

Lutein, Zeaxanthin and the Lens

Oxidative damage to the structure of the eye known as the lens is also common. Lutein and zeaxanthin filter high-energy blue light and function as antioxidants in the lens – functions which can protect this essential eye structure from being damaged. Researchers found that women aged 53 to 73 years with daily lutein plus zeaxanthin intakes of at least 2.4 mg nearly doubled their chances of having optimally-functioning lenses.6 Yet another reason for supplementing with these beneficial carotenoids.

Lutein, Zeaxanthin and the Optic Nerve

Making sure that your eyes contain enough of the natural antioxidants, lutein and zeaxanthin, can ensure continued support for optic nerve health. The optic nerve transmits visual information from retinal tissue to the brain. Thus, damage to the optic nerve can severely affect visual acuity. Ensuring adequate lutein and zeaxanthin intake can protect the optic nerve from free radical damage.

Lutein and Zeaxanthin – Where Do They Come From?

The lutein and zeaxanthin of the macular pigment are entirely of dietary origin (and therefore lutein and zeaxanthin are essential nutrients).2 Lutein and zeaxanthin are found naturally in corn, broccoli, green beans, green peas, brussels sprouts, cabbage, kale, collard greens, spinach, lettuce, kiwi, honey dew, nettles, algae, the petals of many yellow flowers, the yolks of eggs laid by hens fed marigolds and high-quality dietary supplements. The results of a study published recently in the Journal of Nutrition indicate that more of the lutein (and probably zeaxanthin) that you consume can be absorbed if you add a little avocado.7

Recent studies have also confirmed that the more lutein and zeaxanthin one consumes, the more it can benefit eye health. Studies suggest that dietary intake of both carotenoids causes an increase in the amount of carotenoids reaching the eyes and thus able to confer protection from free radical damage.8,9

Pycnogenol

As we know, the normal processes of vision and daily environmental exposures to eye tissue produce vast amounts of free radicals. Overload your eyes with these destructive byproducts of sight and you risk permanent damage to the retina, cornea and lens. Pycnogenol protects the structures of the eye – the cornea, lens and retina – from vision-destroying oxidation.10

Incorporating eye-friendly nutrients into your daily nutritional regimen increases your chances of enjoying worry-free visual function throughout life. Antioxidant nutrients such as ß-carotene, vitamins C and E, Zinc, the carotenoids lutein and zeaxanthin, Pycnogenol and hyaluronic acid can all play a part in ensuring you maintain healthy visual acuity and eye function by providing your visual organs with the nourishment and protection they desire.

Next Best Kept Secrets to Healthy Aging topic:
Skin Health – Nourishing your Insides to Nourish your Outsides

References:
1. Age-Related Eye Disease Study Research Group. A randomized, placebo-controlled, clinical trial of high-dose supplementation with vitamins C and E, beta carotene, and zinc for age-related macular degeneration and vision loss. Arch Opthalmol 2001;119:1417-1436.
2. Beatty S, Boulton M, Henson D, Koh H-H, Murray IJ. Macular pigment and age related macular degeneration. Br J Ophthalmol 1999;83:867–877.
3. Beatty S, Murray IJ, Henson DB, Carden D, Koh H-H, Boulton ME. Macular pigment and risk for age-related macular degeneration in subjects from a Northern European population. Invest Ophthalmol Vis Sci 2001;42:439-446.
4. Richer S, Stiles W, Statkute L, Pulido J, Frankowski J, Rudy D, Pei K, Tsipursky M, Nyland J. Double-masked, placebo-controlled, randomized trial of lutein and antioxidant supplementation in the intervention of atrophic age-related macular degeneration: The Veterans LAST study (Lutein Antioxidant Supplementation Trial). Optometry 2004;75:216-230.
5. Seddon JM, Ajani UA, Sperduto RD, Hiller R, Blair N, Burton TC, Farber MD, Gragoudas ES, Haller J, Miller DT, et al. (1994) Dietary carotenoids, vitamins A, C, and E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group. JAMA 1994;272:1413-1420.
6. Jacques PF, Chylack LT Jr, Hankinson SE, Khu PM, Rogers G, Friend J, Tung W, Wolfe JK, Padhye N, Willett WC, Taylor A. Long-term nutrient intake and early age-related nuclear lens opacities. Arch Ophthalmol 2001;119:1009-1019.
7. Unlu NZ, Bohn T, Clinton SK, Schwartz SJ. Carotenoid absorption from salad and salsa by humans is enhanced by the addition of avocado or avocado oil. J Nutr 2005;135:431-436.
8. Burke JD, Curran-Celentano J, Wenzel AJ. Diet and serum carotenoid concentrations affect macular pigment optical density in adults 45 years and older. J Nutr 2005;135:1208-1214.
9. Rodriguez-Carmona M, Kvansakul J, Harlow JA, Kopcke W, Schalch W, Barbur JL. The effects of supplementation with lutein and/or zeaxanthin on human macular pigment density and colour vision. Ophthalmic Physiol Opt 2006;26:137-147.
10. Dene BA, Maritim AC, Sanders RA, Watkins JB 3rd. Effects of antioxidant treatment on normal and diabetic rat retinal enzyme activities. J Ocul Pharmacol Ther 2005;21:28-35.
11. Aragona P, Papa V, Micali A, Santocono M, Milazzo G. Long term treatment with sodium hyaluronate-containing artificial tears reduces ocular surface damage in patients with dry eye. Br J Ophthalmol 2002;86:181-184.
12. Debbasch C, De La Salle SB, Brignole F, Rat P, Warnet JM, Baudouin C. Cytoprotective effects of hyaluronic acid and Carbomer 934P in ocular surface epithelial cells. Invest Ophthalmol Vis Sci 2002;43:3409- 3415.

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