When I was a little girl, my mother would always tell me that if I ate carrots, I wouldn’t need eyeglasses. I didn’t know whether to believe her or not. At that time, there were not studies available linking eye health with vitamins and nutrition. Eating carrots for good eyesight just seemed like an old wives’ tale to me.
However, in the last decade or so, scientists have made some interesting discoveries which suggest that certain supplements may help keep our eyes healthy.
For example, antioxidants are substances such as vitamins or minerals that both protect the body from forming free radicals and may also destroy free radicals that already exist. Free radicals are comprised of atoms which damage cells, and impair the immune system. As such, free radicals can cause infections and degenerative diseases to occur in the human body.
Antioxidant supplements you can take which may improve your eye health include Vitamins A, C, and E, and minerals such as zinc, magnesium, copper and selenium. They are believed to help arrest age-related macular degeneration (AMD) and cataracts in some individuals.
Macular Degeneration refers to the physical degeneration, or disturbance of a small, capital “O”-sized part of the retina, called the macula. The macula is what we use to read, drive, recognize faces and watch television. It is the leading cause of blindness in people over 55 so there is a degenerative component to the macula which is automatically built into the aging process, or so it would seem.
The incidence of cataracts also seems to increase with age. A cataract causes a cloudiness to appear in the eye’s natural lens. It lies behind the iris and the pupil. Without this “lens”, we can’t focus on objects or even light very well.
Research studies suggest that antioxidants may stall the development process of macular degeneration or cataracts. They may even reduce the risk of developing these diseases among certain high-risk populations.
So, just how much of each antioxidant do we need?
Vitamin A. The recommended daily allowance is 5,000 IU (International Units) for adults. Vitamin A is found in milk, cheese, liver, fish, and dark green, yellow and red vegetables such as carrots, sweet potatoes and kale. (Maybe there was something to that ‘old wives’ tale’, after all.)
Vitamin C. The RDA for Vitamin C is 60 mg (milligrams) per day. Vitamin C is found in a variety of fruits and vegetables including oranges, strawberries, cantaloupes, green and sweet peppers, broccoli, grapefruit and mango.
Vitamin E. Vitamin E is usually found in nuts. Men need at least 10 mg per day; whereas, women require 8 mg. Sunflower seeds, almonds, hazelnuts, peanuts, soybeans and mangoes all provide a big boost of Vitamin E.
Zinc. Adults require at least 15 mg of Zinc per day. Zinc is found in meat like hamburgers, grains and cereals such as wheat, as well as some types of nuts, and shellfish.
Magnesium. Magnesium is a common component of many nuts, beans and dark, leafy green vegetables. 400 mg a day is what most experts recommend for a healthy adult. Magnesium-rich foods include: lentils, black beans, artichoke, chick peas, okra, split peas, spinach, broccoli and tofu.
Copper. You can find this mineral in whole grain products, shellfish, fruit and nuts. Adults require at least 2 mg per day. Copper is found in water, lobster, shrimp and chocolate. Some copper-rich foods can be addictive so they should be eaten in moderation.
Selenium. 70 mcg (micrograms) of Selenium is a normal daily allotment. Brazil nuts, fish, bread and eggs contain selenium.
As we’ve gone through the list so far, it seems that if you eat a lot of green, leafy vegetables, you’ll get a great deal of benefits for your vision. They do include a lot of the vitamins and minerals that help prevent many diseases, including those of the eyes.
If you are still looking for supplementation, you may also look into Lutein and Zeaxanthin. These supplements are known as carotenoids. Carotenoids are the red and yellow pigments in animals and plants. However, they also turn other products, such as beta-carotene, into Vitamin A, which we already know is essential for eye health.
Lutein and Zeaxanthin are pretty closely related. You usually find one with the other. In fact, they do appear together in most fruits and vegetables. The human body also converts Lutein into Zeaxanthin.
You should eat these leafy greens high in Lutein, such as spinach, kale, and collard greens, cooked instead of raw.
The cooking process seems to break down the cells which contain Lutein, thus releasing it and Zeaxanthin.
Of course, many people say that Lutein and Zeaxanthin are more affective than regular antioxidants. They seem to increase antioxidant production, as was mentioned earlier. However, these substances also filter out blue light. Blue light can damage the retina over time and lead to age-related eye diseases. Since the cornea and lens don’t filter blue light out, Lutein and Zeaxanthin perform this vital function and help reduce photo damage of the retina.
These substances have also been shown to protect the blood vessels surrounding the macular region, keeping them strong and less subject to age-related deterioration, a major factor in AMD. The final function they perform is that they reduce the oxidation process of Essential Fatty acids. Basically, Lutein and Zeaxanthin keep these EFAs soluble and strong so that they can perform their functions.
So, what do EFAs do for the eyes?
Essential Fatty Acids are called that because they are needed by the body but not produced by it. A person has to take in EFAs. Fatty acids are the building blocks of fat. Although fat often gets a bad rap, it is beneficial for certain cellular functions.
Infants require EFAs in order for their vision to develop properly. Adults with prolonged EFA deficiencies are more likely to suffer retinal and macular damage, as research studies are starting to suggest.
Essential Fatty Acids, which should be taken in moderation, are found in two types. These are Omega-3s and Omega-6s. Omega-3’s most common derivative is alpha-linolenic acid. Eat plenty of fish such as salmon, cod, and tuna to get at least twice a week. If you don’t like fish, you can try fish oil supplements, which are available at most pharmacies and many health food stores.
The main Omega-6 is Linoleic Acid. You can find it in a variety of vegetable oils such as sunflower, corn, and canola. You can also find it in foods made of these oils, like margarine. Evening primrose supplements also contain a high amount of this essential fatty acid.
Experts do recommend that you don’t overdo these EFAs, especially the Omega-6s. Of course, in the Western world, we seem to consume a lot more of the Omega-6s and not enough of the Omega-3s. Watching your oil intake or switching the oil-based products you eat, can go a long way to helping make the ratio more amenable to promoting good health, including that of your eyes. If you do decide to use a supplement, an Omega-3 supplement only may be to your best benefit.
Most nutritionists would probably agree that you can find all of these vitamins and minerals in a healthy, well-balanced diet. Good nutrition is a lifelong process and one that can prevent many diseases, including cataracts and macular degeneration.
Although it is never too late to embark on a healthy eating plan, it may not hurt to supplement your diet with some of these substances, especially if you are over 55 or at a high-risk for macular degeneration or cataracts.
High-risk factors include for macular degeneration include: high cholesterol, hypertension, obesity, far-sightedness, being a Non-Hispanic Caucasian, and a woman. Cataracts are more common in African Americans, women, diabetics, smokers and those who take steroids.
Before taking vitamin and mineral supplements, you should consult an eye care professional before embarking on any course of supplements to see what he or she would recommend. Amounts of each vitamin and mineral can differ depending upon age, gender and certain health situations.