Vitamin A, also called retinol, is key in fighting vision problems like cataracts, glaucoma, macular degeneration and night blindness. It is found primarily in fish oils, liver, eggs and fortified dairy products. However, if you don't eat animal products, you can make sure you are getting plenty of vitamin A by eating fruits and vegetables that contain carotenoids like beta-carotene, which the body then converts to useful vitamin A, called "provitamin A."
Bright yellow or orange fruits like carrots, apricots and sweet potatoes are good sources of beta-carotene, while green leafy vegetables, especially broccoli, are rich in the carotenoids lutein and zeaxanthin. Unfortunately, some people don't get enough of these foods, and therefore they are lacking in a vitamin essential to their sight. As Gary Null writes in "Complete Guide to Health Nutrition," "The logic is obvious: Without vitamin A, proper vision is impossible."
Vision loss is one of the most feared health conditions, but sufficient vitamin A intake may help ease those fears. Vitamin A helps safeguard sight by protecting against free radical damage that can lead to vision problems like cataracts, macular degeneration and night blindness. While research has linked vitamin A deficiency to a variety of vision problems, one of the first signs that your eyes are not getting enough vitamin A may be episodes of night blindness. Vitamin A is especially important to the rods of the eye, which allow sight in dim light.
In the book "Smart Medicine for Healthier Living," authors Janet Zand, Allan N. Spreen and James B. LaValle write, "The rods are cylindrical-shaped cells on the surface of the retina. They contain a special chemical called visual purple, or rhodopsin, that is responsible for vision in low-light conditions. Rhodopsin is formed from protein and retinol, a form of vitamin A ... if you lack sufficient vitamin A, the production of rhodopsin suffers, leading to increased difficulty seeing in dim light." Therefore, if you are having unusual difficulty driving at night or finding your seat in a dark movie theater, you may want to consider adding some more vitamin A to your diet. The authors of "Smart Medicine for Healthier Living" go on to say that if vitamin A deficiency is severe enough, it could also lead to abnormally dry eyes and even the appearance of white foamy patches called Bitot's spots on the eye's surface.
Cataracts is another common vision concern, especially for elderly patients, that can be prevented with proper nutrition. According to "The Folk Remedy Encyclopedia," cataracts strikes nearly everyone by the age of 75, but this is another problem that can be prevented by adding more vitamin A to the diet. Alan H. Pressman writes in "The GSH Phenomenon" that recent studies have shown that people with a higher dietary intake of mixed carotenes � the vitamin A precursors � along with higher intake of vitamins E and C have significantly lower rates of cataracts. Vitamin A is also particularly important to the elderly, who often don't get enough nutrient-rich foods, because the vitamin can combat weakened immune system function or dry skin problems in older patients.
Although vitamin A is especially vital to properly functioning eyes, it offers many other health benefits as well. It helps fight free radical damage that results from tobacco and other environmental pollutants. Vitamin A is essential for immune system function and helps build and maintain strong, healthy bones. It also regulates cell development and safeguards reproductive health. Vitamin A can also be useful topically to treat skin infections, psoriasis and acne sores. In fact, many acne medications now contain vitamin A as their active ingredient. Vitamin A substances also seem to protect against cancer-causing agents, according to Sheldon Saul Hendler's "Vitamin And Mineral Encyclopedia."
In "Treating Cancer with Herbs," Michael Tierra ND recommends the average person get about 10,000 IU (international units) of vitamin A daily. However, doses higher than that should only be used under medical supervision since too much vitamin A, a fat-soluble vitamin that is primarily stored in the liver, can cause liver toxicity. For that reason, Tierra recommends pregnant women should ingest no more than 8,000 IUs of the vitamin a day.
The health benefits of vitamin A are plentiful, especially in terms of visual health, so if you notice you're having a difficult time seeing at night, you may want to add some yellow and orange veggies to your diet. If it is important to you to protect your vision � and to most of us it is � try safeguarding your sight by eating right. In other words, it's time you listen to your mother, and start eating those carrots.
The experts speak on Vitamin A:
The ubiquitous carrot practically sets the standard for beta-carotene, the plant form of vitamin A. Antioxidants like beta-carotene sponge up free radicals, those unstable molecules that cause many of the ills of advancing years. Among their many benefits, carrots are also noted for helping to prevent cataracts. Never be without them in your refrigerator! A whole medium carrot is only 30 calories.
Superfoods by Dolores Riccio, page 22
Night blindness is often a symptom of retinitis pigmen-tosa, a disease that causes deterioration of the rods (cells that distinguish light and dark) in the retina and progressive loss of sight. Vitamin A and zinc deficiencies can also lead to night blindness.
Alternative Medicine by Burton Goldberg, page 941
Essential for vision and a strong immune system, vitamin A also helps build and maintain strong bones. Found in liver, fish liver oils, whole and fortified milk, and eggs, this vitamin can be synthesized from carotenoids, naturally occurring in orange fruits and some vegetables.
The Diabetes Cure by Vern S Cherewatenko MD and Paul Perry, page 156
The earliest sign of vitamin A deficiency is a decrease in dark adaptation, or night vision. Serum retinol levels are not predictive of subclinical deficiency states. However, classical dark adaptation testing is a cumbersome and time-consuming process (usually taking 45 minutes). A rapid test (6 minutes) was described by Thornton and evaluated by Vinton & Russell. This rapid dark adaptation test (RDAT) has significant clinical utility. The basis for the test is the measurement of the time of the so-called Purkinje shift. This refers to the shifting of peak retinal wavelength sensitivity from the red toward the blue end of the visual spectrum during the transition from day (cone-mediated) vision to night (rod-mediated) vision. When color vision is non-functional, this shift causes the intensity, not the color, of blue to appear brighter than red under dim lighting.
Textbook of Natural Medicine Volumes 1-2 by Joseph E Pizzorno and Michael T Murray, page 219
Because the light-absorbing retinal pigment is composed of vitamin A and protein, which are continually being used up as images are formed, adequate supplies of these nutrients are vital for proper eye function. The combination of nicotine, sugar, and caffeine may temporarily affect vision.
Prescription For Nutritional Healing by Phyllis A Balch CNC and James F Balch MD, page 357
The more vitamin A you get, the more rhodopsin your body is able to produce. Conversely, people with low levels of vitamin A may suffer from night blindness, which can make it difficult to drive after dark or to find your seat in a dark theater.
New Foods For Healing by Selene Yeager, page 120
Vitamin A deficiency can result in night blindness and blindness due to the destruction of the cornea (xerophthal-mia). The ability of vitamin A to prevent these two visual problems and its mechanism of action in doing so is well known.
PDR For Nutritional Supplements by Sheldon Saul Hendle and David Rorvik, page 466
One study showed that only when zinc was added to a vitamin A supplementation program did subjects experience improved night vision.
Off The Shelf Natural Health How To Use Herbs And Nutrients To Stay Well By Mark Mayell, page 311
While much recent research has focused on "exotic" compounds like sulforaphane, broccoli is also chock-full of more common, but still powerful, compounds like beta-carotene. This nutrient, which the body converts to vitamin A, is one of the antioxidants. That is, it helps prevent disease by sweeping up harmful, cell-damaging oxygen molecules that naturally accumulate in the body. High levels of beta-carotene have been linked to lower rates of heart attack, certain cancers, and cataracts. Broccoli is an excellent source of beta-carotene, providing about 0.7 milligram in a half-cup cooked serving. This provides 7 to 12 percent of the recommended daily amount.
New Foods For Healing by Selene Yeager, page 87
Night blindness is often a symptom of retinitis pigmen-tosa, a disease that causes deterioration of the rods (cells that distinguish light and dark) in the retina and progressive loss of sight. Vitamin A and zinc deficiencies can also lead to night blindness.
Alternative Medicine by Burton Goldberg, page 941
Vitamin A is a fat-soluble vitamin stored primarily in the liver. It plays a role in vision, especially night vision, growth, bone development, and reproduction. Unlike water-soluble vitamins, it is not excreted in the urine but accumulates in the body; doses over 25,000 IU per day can cause symptoms after one month. Vitamin A consists of the following components: vitamin A (formerly fat-soluble vitamin A), retinol, retinol 2, retinal, dehydroretinol, retin-oic acid, and beta-carotene. Sources of Exposure: Preformed vitamin A is found in animal meats, particularly liver, and other animal products. The components needed to build vitamin A (such as beta-carotene) are found in vegetables.
Staying healthy In a Risky Environment by Arthur C Upton, page 420
A number of common vitamin and mineral deficiencies occur in the elderly, mainly from not consuming enough fresh, nutrient-rich foods. Vitamin A is commonly low, and this can lead to poor vision, dry skin, and weakened immunity. Thiamine and riboflavin (Bi and B2) may not be adequate in the diet because of low intake of whole grains, and this may affect the skin and energy level. Pyridoxine (B6) is often low, especially with avoidance of whole foods and with eating refined flour products. Folic acid may be deficient because of avoidance of leafy greens, and vitamin B12 may be inadequate because of both low intake and poor absorption.
Staying Healthy With Nutrition by Elson M Haas MD, page 714
Without sufficient vitamin A, the eyes are more susceptible to infection, ulcera-tions, and even blindness. Further, taking therapeutic doses of vitamin A may slow the loss of vision due to retinitis pigmentosa by about 20 percent per year. Take 5,000 international units two or three times daily, and be sure to eat plenty of green and yellow vegetables. Beta-carotene also is a strong antioxidant that prevents free-radical damage. It is a precursor of vitamin A and has many of the same properties, but it does not become toxic in large doses. Take 5,000 international units of beta-carotene two or three times daily.
Smart Medicine For Healthier Living by Janet Zand LAc OMD Allan N Spreen MD CNC James B LaValle RPh ND, page 504
Vitamin A is essential to prevent night blindness and the formation of cataracts.
Optimum Health by Stephen T Sinatra MD, page 94
Zinc's role in alleviating macular degeneration has been thoroughly studied. Zinc deficiency causes deterioration of the macula. This important mineral aids in healing and is a constituent of at least twenty-five enzymes involved in digestion and metabolism. It helps vitamin A to be released from the liver so it can be used in eye tissues. Food sources of zinc include whole grains, brewer's yeast, wheat bran, wheat germ, and pumpkin seeds.
Save Your Sight by Marc R Rose MD and Michael R Rose MD, page 52
While it has been shown that vitamin A is essential for the normal function of eyes, its role in the formation of eye tissues has not been clearly understood. Probably the most sensitive procedure for testing the depletion of vitamin A in domestic animals today is by observing their behavior in semi-darkness.
Nutrition And Physical Degeneration by Weston A Price, page 335
Vitamins are organic substances that are essential for life. They are found in food derived from both animals and plants. Although ancient physicians did not know that vitamins existed, they sensed that food contained substances that had therapeutic value. For example, more than two thousand years ago, folk healers prescribed calves' liver to treat night blindness. What these healers did not know is that liver is an excellent source of vitamin A, which is essential for good vision.
Secret Remedies by Earl Mindell RPh PhD, page 16
Individuals who regularly take the vitamin A are much less likely to develop cataracts than those who fail to supplement. Even a small amount, like 400 I.U. every other day, was protective.
Lifesaving Cures by Dr Cass Ingram, page 63
Eyesight can be protected by taking vitamin A and mineral supplements. Recent finding: People who took 500 mg of vitamin C, 400 international units (IU) of vitamin E, 25,000 IU of beta carotene and 80 mg of zinc had a 25% lower risk for age-related macular degeneration (AMD) than people who did not take these supplements. AMD is a leading cause of blindness. If you are age 55 or older: See your eye doctor to determine your risk of developing AMD and whether taking these vitamins and minerals might be beneficial for you.
Bottom Line Yearbook 2004 by Bottom Line Personnel, page 85
Eyebright is rich in vitamin A and vitamin C. It also contains moderate amounts of the B-complex vitamins, vitamin D, and traces of vitamin E. Eyebright has been used for centuries both as an eyewash and in tea form as a tonic for the eyes. Taken internally, it helps maintain healthy eyes and good vision.
Smart Medicine For Healthier Living by Janet Zand LAc OMD Allan N Spreen MD CNC James B LaValle RPh ND, page 217
Vitamin A helps in many cases to protect tissues during infections and promote rapid recovery, primarily through its support of the health of the skin and mucous lining barriers and its stimulation of mucus production. It also appears to improve antibody response and white blood cell functions. In these ways, vitamin A may be even more helpful in the prevention of infections. By keeping the mucous membranes healthy, it also helps protect against the irritating effects of smoke and pollution.
Staying Healthy With Nutrition by Elson M Haas MD, page 95
Retinoids are naturally occurring synthetic compounds that have similar biological properties to vitamin A (also called retinol). Vitamin A is necessary for the growth, differentiation, and maintenance of epithelial tissues. Epithelial tissues cover the organs of the body, including the skin (Glanze 1996). Because vitamin A and retinoids have similar properties and because topical retinoids have sebosuppressive properties, topical retinoids are frequently used by dermatologists to treat acne. Retinoids are available as over-the-counter and prescription products. However, products with higher retinoid content require a prescription and supervision of a physician.
Disease Prevention And Treatment by Life Extension Foundation, page 20
While large amounts of vitamin A can be toxic, particularly for pregnant women, the natural beta-carotene in foods is not dangerous because the body converts it into vitamin A only as needed.
Prescription For Dietary Wellness by Phyllis A Balch, page 10
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