Most people are aware of the role vitamins and nutrition can play in preventing health problems like cancer and heart disease. But not as many people are aware that most chronic eye diseases are also related to the foods we eat. Our eyes benefit from good nutrition in the same way other parts of our body do.
Nutrition as a science has evolved dramatically over the past hundred years. Doctors used to be concerned only about malnutrition caused by nutritional deficiencies, whereas today we are also concerned about malnutrition caused by excesses of fat, sugar, certain proteins, and overly refined products.
Vitamins and health supplements can be found in a variety of stores, and there are several different types of vitamins to choose from—multivitamins, men’s or women’s vitamins, and even vitamins for the eyes. Eye vitamins are designed to focus directly on eye health. Let’s briefly go over the various types of vitamins and how they benefit the eyes.
Vitamins for the Eyes
Vitamins are classified as either fat-soluble or water-soluble. Fat-soluble vitamins are stored in the body and include A, D, E, and K, while the water-soluble vitamins, C and B, are flushed from your body and need to be replaced daily.
Taking eye vitamins can help us to maintain the health of our eyes. Vitamins for the eyes can also help prevent many diseases. Although we can obtain all the vitamins and minerals we need by eating certain foods, it is nearly impossible in these fast food-oriented times to get a healthy meal with all the vitamins and minerals we need. That is where eye vitamins come in.
- Vitamin A: Vitamin A was the first vitamin thoroughly investigated for its health benefits, hence its name. Not only can it help maintain a strong immune system and healthy skin, vitamin A is essential for keeping the retina healthy and for producing good quality tears that keep the eyes moist. Foods that are rich sources of natural vitamin A include carrots, sweet potatoes, spinach, and apricots. Talk with your eye doctor about the amount of vitamin A you should consume each day. Vitamin A taken in high dosages can be toxic. Patients with a history of smoking (past or present) are particularly more vulnerable to the lung cancer-causing toxic effects of excess vitamin A.
- Vitamin B1: Also known as Thiamin, vitamin B1 acts as a coenzyme for certain chemical reactions in the body, assisting enzymes during those reactions. A deficiency in Thiamin can affect the heart and nervous system. When it comes to the eyes, one study revealed that glaucoma patients had lower levels of Thiamin in their blood than those without glaucoma.
- Vitamin B2: Also called riboflavin, vitamin B2 is essential for helping to control chemical reactions that involve oxidation and reduction. It also helps to maintain adequate levels of the B vitamins niacin and pyridoxine. A deficiency of vitamin B2 can result in skin changes and is known to cause cataracts.
- Vitamin B3: Also called niacin, B3 is like a work horse for coenzymes that produce and break down carbohydrates, fatty acids, and amino acids. Niacin also contributes to the antioxidant defense system against cataracts.
- Vitamin B6: Also called pyridoxine, vitamin B6 not only aids in the formation of and niacin, but also participates in many chemical reactions that involve the nervous system. The way red blood cells function is directly related to vitamin B6, and it plays a critical role in chemical reactions involving amino acids. In general, the more protein you consume, the more vitamin B6 you require. A deficiency can lead to raised levels of certain amino acids in the blood, which increases the risk of heart disease.
- Vitamin B12: Vitamin B12 is involved in manufacturing DNA, and also in the production of protein. A deficiency of vitamin B12 can cause irreversible damage to the brain and spinal cord. Early signs of vitamin B12 deficiency include problems with memory and thinking. Damage can occur to the optic nerve, which causes a decrease in vision. If your diet cannot include an sufficient amount of vitamin B12, you may need to take supplements to avoid serious health problems.
- Folic Acid: Folic acid is also a B vitamin (like niacin and pyridoxine listed above) that helps coenzymes in chemical reactions involving amino acids. A folic acid deficiency can cause anemia, which may put pregnant women at a higher risk for certain birth defects. In the eye, a folic acid deficiency may lead to optic nerve degeneration.
- Vitamin C: Did you know vitamin C is naturally present in your eye’s lens? It also helps prevent cataracts. Vitamin C has many functions throughout the body. For example, it is a key component in the formation of collagen, a structural protein that helps with, among many things, the formation of the connective tissue in the sclera of the eye. It also helps other vitamins, such as vitamin E, restore themselves to an active state. Smokers have a significantly lower amount of vitamin C in their bloodstream than do nonsmokers, and vitamin C is easily destroyed when cooked.
- Vitamin D: Did you know vitamin D is not really a vitamin? In fact, it is a hormone. And unlike other vitamins, which are found in foods and beverages, the best source of vitamin D is the sun. Adequate sun exposure is far preferable to dietary supplementation. When the skin is exposed to the sun, it manufactures vitamin D from a form of cholesterol called 7-dehydrocholesterol. Vitamin D has many functions in the body, ranging from creating and maintaining strong bones to helping regulate calcium levels in the kidneys. One study linked a deficiency of vitamin D to nearsightedness. Experts also believe a vitamin D deficiency may be linked to pinkeye, cataracts, and keratoconus.
- Vitamin E: Like vitamin C, vitamin E is found in the lens of the eye. It is also a major player in the body’s antioxidant defense system. Because it is found in the eye’s lens, it is believed to help prevent cataracts. Vitamin E is also found in the retina, and is said to help prevent macular degeneration. A deficiency in vitamin E can lead to an increased risk for both diseases.
Eye vitamins can be bought without a prescription, except for high dosages meant for people who have age-related macular degeneration (AMD) and require an extra dosage. Over-the-counter vitamins are usually not expensive, and provide most or all of the vitamins and nutrients listed on our eye nutrition page. Dosages range from one to four pills a day, but these will vary. It is also good to note that although these vitamins and minerals are good for us, taking too much of them can be dangerous. The National Eye Institute’s research has found that a specific daily dosage of certain vitamins and minerals is effective in preventing AMD. To learn more, visit the National Eye Institute’s web site.
Ingredient Comparison Chart
Take a look at the various ingredients found in a variety of different eye vitamins:
|Ingredient||Recommended Daily Dosage||Benefits to Eyes and Body|
|Lutein||5 mg||Can prevent age-related macular degeneration|
|Bilberry Extract||10 mg||Improves night vision; contains antioxidants that reduce the risk of eye hemorrhages|
|Citrus Bioflavonoid||250 mg||Found in bilberries and bilberry extract; increases blood flow in small blood vessels on retina; increases blood flow to the macula; reduces chances of age-related macular degeneration|
|Omega 3 Flax Meal||500 mg||Plays a key role in retinal health, aids lacrimal drainage system and regulates intraocular pressure; reduces risk of age-related macular degeneration by 39%|
|Beta-Carotene||25,000 IU||Converts into vitamin A, which plays a key role in the bio-electrical process of vision; helps eliminate damaged cells in eyes|
|Vitamin A||5,000 IU||Helps with day-to-day vision; keeps vision clear and sharp, especially at night|
|Vitamin C||1,000 mg||Reduces risk of cataract development; contains antioxidants that prevent or delay age-related macular degeneration; regulates intraocular pressure, which reduces the chances of optic nerve damage and glaucoma|
|Natural Vitamin E||200 IU||When taken with other antioxidants it helps prevent cataracts and age-related macular degeneration|
|Vitamin B2||40 mg||Strengthens cornea through a process called collagen linking; stops onset of keratoconus|
|Rutin NF||100 mg||Contains antioxidant and anti-inflammatory properties that benefit the entire body; strengthens certain capillaries|
|Selenium||100 mcg||Helps to absorb vitamin E and coverts it into an antioxidant that maintains the eyes’ overall health|
|Chromium||200 mcg||Reduces blood sugar levels, which preserves the strength of smaller blood vessels, especially those located in or around the retina|
|Zinc||25 mg||Helps the body absorb and convert vitamin A; helps protect against age-related macular degeneration and night blindness|
* Chart courtesy of information found on QuantumHealth.com
Choosing an Eye Vitamins Brand
When choosing a brand of eye vitamins it is a good idea to compare vitamin and mineral content to daily requirements, and of course, prices. Vitamins made for the eye should contain Vitamins A, C, E, B2, and the minerals Zinc and Selenium.
Eye vitamins now may contain the newly discovered antioxidant Lutein. Lutein is an antioxidant whose true value is still being studied, but it is already attracting much attention. Lutein is concentrated mostly in the retina, lens, and macula, which suggests that it helps keep the eyes healthy.
It bears repeating here; be careful when taking specially formulated eye vitamins. This is especially critical for smokers, as tests have linked beta-carotene to certain diseases in smokers such as lung cancer. So, if you are a current or past smoker, it is better to look for eye vitamins with no beta-carotene.
Macular Degeneration — the Latest Research
The NEI (National Eye Institute) has been studying the effects of vitamins on age-related eye diseases since 1992 with their Age-Related Eye Disease Studies (AREDS 1 1992-2001 and AREDS 2 2006-2011). With some changes and substitutes in vitamin formulation over the years of these long-term studies, the current results suggest in summary:
- Vitamins containing beta-carotene increase the risk of lung cancer in patients with a history of smoking.
- Vitamins containing Lutein and Zeaxanthin work as a good substitute for beta-carotene.
- While omega-3 seems to be beneficial for dry eye and other bodily functions, their benefits regarding age related macular degeneration are not proven.
- Formulations containing only 25 mg of zinc are just as effective as those containing 80 mg of zinc.
- The biggest benefits of vitamins for the eyes were seen in patients with mild or early disease. Taking the right vitamins helps prevent progression to more advanced diseases.
- On the other hand, for patients with no age-related eye disease, taking vitamins does not seem to have much effect in preventing disease from starting.
Here are some questions to ask your eye doctor about eye vitamins:
- Which over-the-counter eye vitamins would you recommend for me?
- Which vitamin could I use more of?
- Where can I get more information about eye vitamins?
- Can I get eye vitamins through you?
- How much time should I spend in the sun every day to get enough vitamin D?
- What are my best sources for the various vitamins I should be taking?
Did you know … your brain and visual system account for 2 percent of your body weight, but use up about 25 percent of your nutritional intake?
- Quantum Health, Eye Vitamins http://www.quantumhealth.com/productgroups/eyes.html
- J. Anshel, MD “Smart Medicine for your Eyes” (Quantum Publishing, 2011) 68-82
- J. Lavine, MD “The Eye Care Sourcebook” (McGraw-Hill books, 2001) 277-294
- National Eye Institute http://www.nei.nih.gov/areds2/PatientFAQ.asp