7 essential nutrients for eye health & better vision

The retina and your eyes are like super computers. The retina at the back of your eye has been found to process about ten one-million-point images per second. It takes robot vision programs about 100 computer instructions to derive single edge or motion detections from comparable video images. It takes fuel to power that computer!

Our eyes represent less than 1% of our body weight, yet require 25% of our nutritional intake. They can use one-third as much oxygen as our heart.

Some degenerative eye diseases such as age-related macular degeneration (AMD or ARMD) are highly responsive to diet and dietary changes. But there is no need to wait until your vision deteriorates in order to eat for eye health!

man holding kiwis in front of his eyes

In this article, we will break down evidence-based facts about the best micronutrients for healthy eyes and where to find them in natural food sources.

  1. Astaxanthin

  2. Zeaxanthin

  3. Vitamin E

  4. Vitamin A

  5. Omega-3 fatty acids

  6. Zinc

  7. Resveratrol



Astaxanthin


Astaxanthin is a fat soluble carotenoid pigment with a pinkish color. It is particularly good for eye health because it bypass the blood-brain barrier and blood-retinal barrier, to fight free radicals in the brain and directly improve vision.


It has been linked [1] to improved blood flow, and shown to lower oxidative stress in smokers and overweight people. A comparison study [2] of astaxanthin and other carotenoids showed that it displayed the highest antioxidant activity against free radicals. It is up to 500 times a stronger than vitamin E.


Where to find astaxanthin:

  • trout and Pacific salmon

  • micro-algae

  • yeast

  • shrimp

Zeaxanthin

yellow colored fruit banana pineapple and lemons

Zeaxanthin, along with Lutein is one of the only 2 carotenoids that accumulate in the retina, particularly the macula region, at the back of your eye.

Zeaxanthin helps build a yellow-colored shield to protect the eye cells from the harmful effects of high-energy blue and ultraviolet light, such as the sun or computer screens.

Zeaxanthin has been studied as protective factor in age-related macular degeneration (AMD) [3], uveitis [4], cataracts [3] and diabetic retinopathy [5]



In a study published in the journal Optometry, participants with early AMD who consumed 8 mg per day of dietary zeaxanthin for one year improved their night driving and their visual acuity improved an average of 1.5 lines on an eye chart.


Zeaxanthin has been studied as protective factor in age-related macular degeneration (AMD) [3], uveitis [4], cataracts [3] and diabetic retinopathy [5]


Where to find zeaxanthin:

  • dark green vegetables such as kale

  • orange and yellow fruits

  • egg yolks

Vitamin E


Vitamin E is another antioxidant that protects the eyes.


In one study on 3,640 people with AMD over 7 years, it was proved that taking 400 IU of vitamin E along with several other nutrients (in a daily supplement called AREDS) reduced the risk of progressing to advanced stages by 25% [6]. In addition, some studies suggest that diets high in vitamin E may help prevent age-related cataracts.


Main dietary sources of vitamin E include:

  • almonds, hazelnuts, pine nuts, peanuts, brazil nuts

  • sunflower seeds

  • wheatgerm oil, sunflower oil

  • avocado, mango, turnip greens

  • salmon and trout

Vitamin A


You've probably heard about this one! Whereas the previous nutrients in this list targeted the retina at the back of the eye, Vitamin A's key role for vision is to protect the cornea, which is the outside covering of your eye.Vitamin A is also a building block of rhodopsin, a protein in your eyes that allows you to see in low light conditions [7].


Vitamin A deficiency is rare in developed countries, but it can lead to serious vision loss problems. The first sign of vitamin A deficiency is night blindness. If left untreated, your tear ducts and eyes can dry out. Eventually, the cornea softens, resulting in irreversible blindness.

Studies suggest that diets high in vitamin A may be associated with a reduced risk of cataracts [8] and age-related macular degeneration (AMD) [9].

Vitamin-A-rich foods are

  • Sweet potatoes and carrots

  • leafy green vegetables

  • broccoli

  • pumpkins

  • sweet red bell peppers

  • beef liver and cod liver oil


Omega-3 fatty acids


Omega-3 fatty acids are a type of polyunsaturated fat (the good kind of fat!). Omega-3 fatty acids are important for proper visual development and retinal function. Studies in infants show that getting enough omega-3s in the diet is crucial for optimal visual development.


Besides helping form the cells of your eye, omega-3 fats have anti-inflammatory properties which may play a role in the prevention of diabetic retinopathy (DR). A review of 31 studies suggested that diets high in oily fish — such as the traditional Mediterranean diet — may protect against DR. Omega-3 fats may also benefit individuals with dry eye disease by helping them produce more tears.


Zinc


Zinc plays a crucial role in bringing vitamin A (see above) from the liver to the retina in your eye, in order to produce the protective pigment called melanin. There are high levels of Zinc in your macula.


In one study, older adults with early macular degeneration were given zinc supplements. Their macular deterioration slowed, and they maintained their visual sharpness better than those who received a placebo [10].


However large amounts of zinc can impact your body's ability to absorb copper, which is why supplements that contain zinc usually come with extra copper. You should be adding 2 milligrams per day of copper if you are taking zinc supplements. Natural sources of zinc include:

  • Oysters, Lobster

  • Beef and pork

  • Baked beans

  • Cashew nuts

Resveratrol


Resveratrol is know as the healthy compound in red wine, showing a lot of health benefits for cardiovascular health and cancer prevention. Recently, it has been observed inside the eye, meaning it is able to cross the blood-ocular barrier and end up in the conjunctiva, aqueous fluid and vitreous fluid parts of the eye.[11]

grapes for resveratrol

Resveratrol increases blood perfusion, has anti-inflammatory effects, and reduces oxidative stress and angiogenesis.


Resveratrol has been suggested to be helpful in the following:

  • dry eye

  • glaucoma

  • cataracts

  • age-related macular degeneration (AMD)

  • diabetic retinopathy (DR).



Best sources of resveratrol include foods such as peanuts, pistachios, grapes, red and white wine, blueberries, cranberries, and even cocoa and dark chocolate.


References


[1] Kidd P. Astaxanthin, cell membrane nutrient with diverse clinical benefits and anti-aging potential. Altern Med Rev. 2011 Dec;16(4):355-64. PMID: 22214255.


[2] Naguib YM. Antioxidant activities of astaxanthin and related carotenoids. J Agric Food Chem. 2000 Apr;48(4):1150-4. doi: 10.1021/jf991106k. PMID: 10775364.


[3] American Optometric Association. Lutein & Zeaxanthin.


[4] Yadav UC, Kalariya NM, Ramana KV. Emerging role of antioxidants in the protection of uveitis complications. Curr Med Chem. 2011;18(6):931–942. doi:10.2174/092986711794927694


[5] Hu BJ, Hu YN, Lin S, Ma WJ, Li XR. Application of Lutein and Zeaxanthin in nonproliferative diabetic retinopathy. Int J Ophthalmol. 2011;4(3):303–306. doi:10.3980/j.issn.2222-3959.2011.03.19


[6] 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: AREDS report no. 8. Arch Ophthalmol. 2001 Oct;119(10):1417-36. doi: 10.1001/archopht.119.10.1417. Erratum in: Arch Ophthalmol. 2008 Sep;126(9):1251. PMID: 11594942; PMCID: PMC1462955.


[7]Ross A. Vitamin A and Carotenoids. In: Shils M, Shike M, Ross A, Caballero B, Cousins R, eds. Modern Nutrition in Health and Disease. 10th ed. Baltimore, MD: Lippincott Williams & Wilkins; 2006:351-75.

[8] Wang A, Han J, Jiang Y, Zhang D. Association of vitamin A and β-carotene with risk for age-related cataract: a meta-analysis. Nutrition. 2014 Oct;30(10):1113-21. doi: 10.1016/j.nut.2014.02.025. Epub 2014 Mar 12. PMID: 25194611.


[9]Seddon JM, Ajani UA, Sperduto RD, Hiller R, Blair N, Burton TC, Farber MD, Gragoudas ES, Haller J, Miller DT, et al. Dietary carotenoids, vitamins A, C, and E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group. JAMA. 1994 Nov 9;272(18):1413-20. Erratum in: JAMA 1995 Feb 22;273(8):622. PMID: 7933422.


[10] Newsome DA, Swartz M, Leone NC, Elston RC, Miller E. Oral zinc in macular degeneration. Arch Ophthalmol. 1988 Feb;106(2):192-8. doi: 10.1001/archopht.1988.01060130202026. PMID: 3277606.


[11] Shuaishuai Wang, Zheng Wang, Shuo Yang, Tiemei Yin, Yaoli Zhang, Yuanjun Qin, Robert N. Weinreb, Xufang Sun,"Tissue Distribution of trans-Resveratrol and Its Metabolites after Oral Administration in Human Eyes",Journal of Ophthalmology,vol. 2017,Article ID 4052094,12pages,2017.https://doi.org/10.1155/2017/4052094


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