Mother always told you to eat your fruits and vegetables – but why? Modern researchers are finding more and more about antioxidants for health. Scientists publish mountains of peer-reviewed research a year on antioxidants found in fruits and veggies. One type of antioxidant is called “phytonutrients.” Found in plant pigments, phytonutrients are especially good for the eyes and brain. How do phytonutrients slow the impact of aging and reduce disease risk? Which foods contain significant amounts of the best types of phytonutrients?
How Antioxidants Work
A particle that lacks an electron is unstable. Called a “free radical,” this particle tries to steal an electron to become stable. In the body, free radicals attack healthy cells, trying to take an electron. The attack damages the cells’ membranes. We can see some of the damage in the form of wrinkles, for example, and diseases associated with aging. Antioxidants act as a defender against free radicals. They donate an electron to the unstable free radical. As a result, the cells in the body age more slowly.
We get antioxidants primarily through food and supplements, although some are produced within the body. Scientists have made a long list of antioxidants. One major category of antioxidant is phytonutrients.
Types of Phytonutrients1
The root word “phyto” means “plant” in Greek. We get phytonutrients in our diet from plants. For example, many fruits, vegetables, nuts, beans, whole grains, mushrooms, and tea leaves contain phytonutrients.
Plants make phytonutrients to protect themselves from attacks. Threats include insects, germs, and fungi. Researchers have identified more than 25,000 phytonutrients in plant-based foods. In this article, we will discuss the most important carotenoids and flavonoids for eye health.
Crossing the Blood-Brain Barrier
The eye is made from nutrients. Therefore, your eyes are literally what you eat. Most of the nutrients below can cross the blood-brain barrier. Did you know that the retina, at the back of the eye, is brain/neural tissue? Nutrients that are good for the brain are generally also good for the retina. Retinal cells respond to light, converting light into electrical signals. The signals travel through to retinal to the optic nerve then and visual cortex in the brain. This creates vision.
As a small, nutrient-hungry organ, the eye is highly sensitive to free radical damage. The eyes are the second most physiological active organ in one’s body next to the brain. Free radical damage over time is a contributing and often causative factor in many age-related eye diseases. Thus, your body needs antioxidants that can reach the eye and brain. A diet low in fruits and vegetables is an invitation for eye disease — and worse!
Phytonutrient-Rich Fruits and Vegetables
The best way to get phytonutrients is by eating fruits and vegetables and their juices. Failing that, you can also take supplements (pills, extracts, chews, herbs, and drinks). In particular, be sure to include these specific superfoods. Research shows that they are especially helpful for the eyes and brain.
Note: Drinking canned or bottled juice is inferior to making fresh juice. Juice can contain large amounts of natural sugars, so do not take too much.
Brightly Colored Fruits and Vegetables – Carotenoids
Carotenoids are a family of phytonutrients. They are pigments in plants that have powerful antioxidant powers.
Red: Lycopene. Tomatoes, watermelon flesh, and red peppers get their color from the carotenoid Lycopene. Lycopene lowers the risk of cataracts and macular degeneration, according to many studies.2. Also, low levels of lycopene are associated with macular degeneration.3
Yellow/Green: Lutein. Corn and egg yolks, plus these green foods: salad greens, lettuce, brussels sprouts, broccoli, collards, kale, mustard greens, and collards. These foods are rich in lutein. (Note: the chlorophyll in these green foods mask the yellow lutein.) Supplements can be made from marigold flowers. Lutein is present in the eye’s macula and lens. This antioxidant helps protect the eyes from sun damage. Lutein plays a role in preventing macular degeneration4 and cataracts.5
Green/Red/Yellow: Zeaxanthin. Kale, cooked spinach, chard, collards, chicory greens, mustard greens, turnip greens, hot chili peppers, and basil (i.e., pesto) are highest in zeaxanthin. Peas, egg yolks, romaine lettuce, summer squash, and Brussels sprouts also have lots of this nutrient. This carotenoid along with lutein helps filter out the sun’s rays, protecting the eyes from ultraviolet damage. Zeaxanthin is a retinal pigment that appears to play a role in preventing macular degeneration.6 Many of these foods are also high in lutein. The combination of these two nutrients has been studied frequently.7.
Blue/Purple: Flavonoids. Blueberries are an excellent source of flavonoids, including anthocyanidins. Numerous studies show a strong relationship between eating blueberries and slower cognitive decline in seniors8. People who have cognitive decline have had improvements in their thinking abilities while eating blueberries each day. 9 Blueberries help delay the onset of Parkinson’s disease10, circulation problems11, and Alzheimer’s disease12. Fresh blueberries may be underripe (bitter) or too expensive out-of-season. In that case, buy frozen wild blueberries and add them to smoothies and pancakes.
Tea, Bilberry, Red Onion – Flavonoids
Flavonoids are pigments in plants that protect them from ultraviolet radiation. They also attract insects for pollination. And they stimulate biochemical reactions in plants. Certain flavonoids are especially important to the eyes.
Catechins are strong antioxidants that are among the cheapest and easiest to find. Brew green tea about 175 degrees for less than two minutes. Dark chocolate is also rich in catechins. Enjoy apples, pears, cherries, blackberries, raspberries, beans, and red table wine.
Quercetin helps prevent capillaries in the retina from leaking and reduces sun damage. The optic nerve, macula, and lens need quercetin to stay healthy. This flavonoid is found in green tea, black tea, apples, red grapes, citrus foods, red onion, leafy greens, broccoli, tomatoes, honey, and most berries.
Rutin also protects the delicate capillaries of the retina.13 Eat or drink the juices of citrus fruits (oranges, lemons, limes, white grapefruit), cranberries (cranberry juice), peaches, apples, and grapes. Also, eat green cabbage, spinach, kale, onions, asparagus, mulberry, and garlic. Buckwheat also contains rutin and makes a tasty pancake.
Bilberry, a relative of the blueberry, is a vision superfood. A strong antioxidant, the flavonoids in bilberries help protect the eye from blue light damage. Bilberries help keep the vascular system in the eye — and the whole body — stronger. Researchers suggest that bilberry may help with cataracts,14 macular degeneration,15 poor night vision, and diabetic retinopathy. If you do not have access to whole bilberries, take supplements or extracts.
Your mom was right! Eat your vegetables and fruit to stay healthy. Antioxidants help protect the tiny parts of the eyes from cumulative free radical damage. Food plants contain phytonutrients, including carotenoids and flavonoids. Middle-aged people can help ward off future eye disease with proper nutrition. Seniors are especially vulnerable to eye disease. Ironically, they need fewer calories and have less efficient absorption. Therefore, taking supplements helps ensure that you get enough antioxidants for vision (and brain) health.
- https://www.webmd.com/diet/guide/phytonutrients-faq#1 ↩
- Researchers: Veronica Castro Lima, et al. Published: Macular pigment in retinal health and disease, International Journal of Retina and Vitreous, August, 2016. – https://www.naturaleyecare.com/study.asp?s_num=20 ↩
- Researchers: Julie A. Mares-Perlman, et al Published: Archives of Ophthalmology, December, 1995. https://www.naturaleyecare.com/study.asp?s_num=89 ↩
- Researchers: Department of Veterans’ Affairs, Medical Center Eye Clinic in Chicago. Published: April 2004 issue of the journal Optometry https://www.naturaleyecare.com/study.asp?s_num=19 ↩
- Researchers: A. Manayi, et al.Published: Lutein and cataract: from bench to bedside, Critical Reviews in Biotechnology, June, 2015 https://www.naturaleyecare.com/study.asp?s_num=115 ↩
- R. Estevez-Santiago, et al, Lutein and zeaxanthin supplied by red/orange foods and fruits are more closely associated with macular pigment optical density than those from green vegetables in Spanish subjects, Nutrition Research, November, 2016. ↩
- https://www.naturaleyecare.com/study.asp?s_num=20 ↩
- Ann Neurol. 2012 Jul;72(1):135-43. doi: 10.1002/ana.23594. Epub 2012 Apr 26. Dietary intakes of berries and flavonoids in relation to cognitive decline. Devore EE1, Kang JH, Breteler MM, Grodstein F. ↩
- Devore, E.E. Kangs, J.H. Breteler, M.M., Grodstein, F.A. (July 12, 2012). “Dietary intakes of berries and flavonoids in relation to cognitive decline.” Neurology. 72(1):135-43. Doi: 10.1002.ana.23594. Epub 26, 2012 ↩
- Ono et al., 2003; Savaskan et al., 2003; Marambaud et al., 2005; Alzheimer’s Association, 2008; Pandey and Rizvi, 2009. ↩
- Pandey and Rizvi, 2009 ↩
- Alzheimer’s Association, 2008 ↩
- L. Navarro-Nunez, et al, Apigenin Inhibits Platelet Adhesion and Thrombus Formation and Synergizes with Aspirin in the Suppression of the Arachidonic Acid Pathway. Journal of Agricultural and Food Chemistry 56 (9): 2970-6, 2008. ↩
- https://www.naturaleyecare.com/blog/more-good-news-about-antioxidants-bilberry-may-ward-off-cataracts-and-macular-degeneration/ ↩
- “Dietary supplementation with bilberry extract prevents macular degeneration and cataracts in senesce-accelerated OXYS rats”, Fursova et al., Adv Gerontol, 2005; 16: 76-9. ↩