How to Solve Vision Problems Naturally
We know good nutrition is more involved than that, that the best diet is one that serves our total needs. Sometimes, though, in spite of ourselves,we end up relying on one specific food targeted to knock out one specific ailment.
Good eyesight, for example, has traditionally been associated with vitamin A alone. However, now a growing body of research indicates that a host of nutrients other than vitamin A may be required for the maintenance of healthy eyes, and some researchers are suggesting that poor nutrition might even be involved in ordinary short-sightedness.
Ben C. Lane, a New Jersey optometrist, found significant differences in the way his more short-sighted patients were eating. The eye, he believes, is particularly sensitive to the body's nutritional state.
'We may say a healthy person can be short-sighted,' Dr. Lane told us, 'that with myopia you can have good health. But I think myopic people's resistance to environmental stresses is reduced in ways that do not show up in an ordinary doctor's examination. It's a subtle difference, and optometrists and ophthalmologists are in a better position to notice the difference. The eye is a magnificent place to observe these things. It's very sensitive to nutritional problems. ' The eye is certainly a complex organ and the different parts require a variety of nutrients to function properly. Vitamins A, E, C, B-complex, and zinc are all essential.
The eye's structureA number of different kinds of tissue in the eye are necessary for sight. The eye is a ball filled with jelly-like fluid. the tissue surrounding this fluid is called the sclera, which is visible as the whites of our eyes in front, but extends back around the eye as well. The very front of the eye is covered by transparent tissue called the cornea.
Light enters the eye here, passes through the lens directly behind the cornea and is focused on light-sensitive cells lining the inner wall at the back of the eyeball. When everything is working properly, the cornea and lens bend the light as it enters the eye and focuses it on the back wall of the eye (called the retina), which activates the optic nerve. The optic nerve sends a message to the part of the brain that registers sight, and we see the focused image.
Vitamin AThe best-known connection between diet and sight involves vitamin A. The retina is made up of light-sensitive cells called cones and rods. The cones are sensitive to color, while the rods are only able to detect different shadings of light. The rods contain a pigment called rhodopsin, which is a chemical cousin of vitamin A. When light strikes a rod, its rhodopsin is chemically broken down and can be restored to working order only if vitamin A is present.
In this case, a vitamin is a very stuff from which vision is 'made'. If the body is lacking in vitamin A, the natural restoration of rhodopsin to working order does not take place, and the rods quit working. The first sign of the breakdown is a loss of night vision, in dim light when the eye can no longer distinguish colors and must rely totally on its black-and-white vision. Proper night vision is totally dependent on the rods, and vitamin A. In severe cases of vitamin A deficiency, there is extensive damage to the cornea as well, but the center of vitamin A's action seems to be in the retina.
(See also NIGHT BLINDNESS.)
Vitamin EOther nutrients have been shown to aid vitamin A. Scientists working at the US government's National Institutes of Health laboratories demonstrated the close interaction of vitamin E with vitamin A in the retina (Investigative Ophthalmoloo and Visual Science, July 1979).
Tests with rats showed that vitamin E had an important effect on how much vitamin A was available for use in the eyes, but it was also shown to have a direct effect on the retina. Rats fed diets containing no vitamin E, but adequate vitamin A developed significant retinal damage.
When the diets were deficient in vitamin A as well, the same damage occurred, plus an additional loss of light-sensitive rods and cones in the retina. 'Rods and cones were involved equally,' the scientists reported, 'and their pattern of loss was not like that found in vitamin A deficiency.' The lack of vitamin E seemed to compound the damage usually done by a lack of vitamin A.
A number of other studies have explored the effects of vitamin E, or the lack of it, on the health of the eye. W. Gerald Robison, Jr, chief of the experimental anatomy section, Laboratory of Vision Research of the National Eye Institute in the United States, has been examining the effects on animal retinas of diets deficient in vitamins E and A. Results? 'A highly E-deficient animal will go blind in time,' he said.
Although he cautions that his work so far has been with animals only and that it's unlikely a human would develop vitamin E deficiencies as extreme as those he's produced in the lab, Dr. Robison's studies have produced some intriguing clues into the nourishment of the eye.
The retina changes light (via chemistry) into electrical impulses, the language of the nervous system. The cells it's made of, Dr. Robison explains, especially the light-sensitive or photoreceptor nerve cells — the things we 'see' with — contain large amounts of unsaturated fatty acids. Because these fatty acids are readily oxidized (broken down by oxygen, or 'rusted out'), 'we can suspect that the retina is quite susceptible to oxidation unless it's protected by an anti-oxidant,' he says.
Because vitamin E is a potent anti-oxidant, or protective agent against organic 'rust', Dr. Robinson decided to test the effect of a grossly E-deficient diet on the retinas of rats. He also tested the effects of diets that were deficient in both vitamin E and vitamin A.
After five months, he told us, a diet low in vitamin E but adequate in A 'produced a significant degeneration of photoreceptor cells, and an accumulation of aging pigments [highly oxidized, insoluble fatty acids] that was five times greater than normal.' Because the visual cells were damaged but not killed, he says, 'the damage may be reversible.' A diet deficient in both A and E, on the other hand, resulted in the permanent destruction of nearly half the visual cells in eight months. 'Vitamin A,' he concluded, 'appears to protect against this cell loss. '
In another study at Cornell University, dogs fed diets deficient only in vitamin E were also found to develop retinopathy or damaged retinas. The damage first showed up on the retina after as little as three months. Next came night blindness and finally 'severe day visual impairment' (American Journal of Veterinary Research, January 1981).
Other nutrientsZinc is also closely tied to vitamin A in maintaining good vision. One of the highest concentrations of zinc in the body occurs in the retina of the eye. Zinc is necessary to keep blood levels of vitamin A at the proper level and to mobilize it for use from its storage place in the liver. Animal studies conducted at Harvard University have shown that 'zinc deficiency can interfere with the metabolism of vitamin A, especially in the retina' (Journal of Nutrition).
Revealing studies of zinc and vision were carried out by scientists at the University of Maryland. The researchers treated six patients suffering from cirrhosis of the liver and night blindness, a common complication of that disease and, as we have seen, of vitamin A deficiency. One patient, given both vitamin A and zinc from the start of the study, regained normal night vision within a week. Three patients treated with zinc alone also returned to normal.
However, two patients fed vitamin A alone for a period of two weeks did not do as well. Although one improved, the other showed no response at all. Only when zinc was added to their treatment did their sight return to normal (American Journal of Clinical Nutrition).
Other nutrients are involved in good vision, in ways that have no apparent connection with the action of vitamin A on the retina. A study of some 900 schoolchildren in India revealed some interesting connections between the B vitamins and general good vision. The children were screened for signs of possible B vitamin deficiency and had their vision tested. One month later, the tests were repeated.
Of the 715 children with evidence of vitamin B complex deficiency, 126 (17 percent) had altered acuity of vision, whereas of 247 children without signs of vitamin B complex deficiency, only 6 (2 percent) had altered visual acuity. There was a significant association between different vitamin B complex deficiency signs on the one hand and visual defects on the other. [British Journal of Nutrition]The clincher, however, came when the researchers tested the effects of B vitamin supplementation on the children's vision. When supplemented children were examined after one month, B vitamin intake was found to be closely associated with improvement in vision. 'While 56 of 70 supplemented children had shown improvement, only 4 of 26 of the unsupplemented children had improved. '
Thiamin (vitamin B1) has been used in other studies to correct disorders of the optic nerve interfering with normal vision. Here the problem was not with the sensitive cells receiving the image but with the nerves that carry the image to the brain. Studies have shown that thiamin-deficient diets cause degeneration of the optic nerve in rats (Medical Journal of Australia). In other research, two ophthalmologists examined people on special diets who did not seem to be getting enough thiamine. In all four cases, the patients suffered similar losses of vision near the center of their visual field. And in all four cases, the problem was corrected when the patients were given thiamin supplements (British Journal of Ophthalmology).
At John Hopkins Hospital in Baltimore, David L. Knox, associate professor of ophthalmology, has been exploring the effect of folic acid, vitamin B12 and other nutrients on an unusual eye problem called 'nutritional amblyopia'. Although his results are still unpublished, he says, 'I've been studying the possibility that folic acid or some other unknown vitamin from green and yellow vegetables may be essential to the maintenance of normal vision and optic nerve function.' It is, he says, 'extremely important for people to eat enough green and yellow vegetables to maintain normal vision. '
MSG affects the eyeSome food additives, particularly monosodium glutamate (MSG), may have a less-than-wholesome effect on the eye according to John Olney, professor of psychiatry and neuropathology at Washington University in St Louis, Missouri. Glutamate is a naturally occurring substance that is harmless when it's part of a protein molecule. However, when it's added to commercial foods in large amounts (as a flavor enhancer), it may damage nerves in the retina and parts of the brain by 'exciting them to death'.
Although Dr. Olney's animal studies have involved the ingestion of massive doses of MSG, well beyond the amounts the average adult would ingest, he said that 'I would definitely go out of my way to avoid feeding MSG to children. ' While adults have well-developed barriers to the toxic effects of glutamate, he explained, a child's system is less fully developed and thus more vulnerable to visual and brain-cell damage.
Preventing cataracts with good nutritionRiboflavin (vitamin B2) has been linked to the prevention of cataracts, another of the many disorders that can rob us of our vision. Cataracts are a clouding of the lens that focuses the image on the back of the eye. Scientists have produced this clouding in several kinds of fish by feeding them diets lacking riboflavin. When researchers at the University of Alabama tested cataract patients for riboflavin deficiency, they found that 8 out of 22 were not getting enough riboflavin.
Our data suggest that riboflavin deficiency may play a role in cataract development in man. Exploration of this possibility is particularly attractive because the administration of riboflavin [is] easily accomplished and might lead to either the prevention or regression of cataract formation. [Lancet]Vitamin C might also be involved in preventing cataracts. Scientists at the University of Maryland have found that vitamin C protects the lens against chemicals normally produced by the action of light. That finding was particularly interesting, given the high concentration of vitamin C naturally found in the lens of the eye and in the fluid directly in front of it, between the lens and the cornea. In fact, the concentration of vitamin C in that fluid, called the aqueous humor, is among the highest of any of the various fluids in the body.
'These findings,' the University of Maryland scientists said, 'further emphasize the concept of the importance of essential nutrients in prevention of certain forms of cataracts' (Proceedings of the National Academy of Sciences, USA, July 1979).
A special form of cataracts triggered by high levels of sugar in the body can occur in diabetics, and, again, essential nutrients are important in preventing their formation. The bioflavonoids, a class of nutrients that complement the action of vitamin C, have been shown to inhibit the action of the enzyme that may set off the formation of diabetic cataracts.
The importance of lightingTo do their best, older eyes need proper nutrition, exercise, rest and, above all, sufficient and proper lighting. Strangely, many people who are conscientious about the first three factors ignore the last. They fail to realize that older eyes need more and better light.
We can't always control the amount and quality of light in our environment, but even when we can, we often don't do as well as we might. A study at London's St Bartholomew's Hospital measured the visual acuity of 56 older Britons (average age 76) in their homes and in a controlled clinical setting. They concluded that 'general levels of lighting are often so poor in the homes of elderly people that the number of people functioning as 'blind' is twice what it need be.' Just turning up the wattage of existing lighting, they discovered, improved vision in 82 percent of the subjects (Lancet, 24 March 1979).
Commenting on these and other experiments, ophthalmologist M.J. Gilkes criticizes health-care workers for assuming that people who complain of vision problems automatically need stronger glasses: 'The only reasonable initial response to the cry "I can't see" is "Are you sure you have got an adequate light?"' (British Medical Journal, 23 June 1979). Clearly, the answer to that question is often 'no'.
Although vision loss is a lifelong process, it manifests itself most noticeably in middle age. Numerous clinical studies have detailed the plight of the aging eye. Dr. Philip C. Hughes, a lighting expert, and Dr. Robert M. Neer of Harvard Medical School have summarized the research for an issue of the journal Human Factors. They paint a gloomy picture: as the eye ages, the lens becomes clouded and less pliable, and the pupil decreases in size. Less light reaches the retina, and near focusing ability declines.
The loss of near focusing ability, called Presbyopia (i.e. long-sightedness), is easily corrected by prescription lenses, but the reduction of light entering the eye is another story entirely. Drs Hughes and Neer cite research that pegs the reduction of light reaching the retina at 50 percent by age 50 and 66 percent by age 60. In some people, the opacity or cloudiness of the lens drastically reduces the light usable for vision. We say they have 'cataracts', and eventually, they must have the lens removed. For most people, though, the gradual darkening of the lens and decrease in pupil size simply mean that they don't see as well, and there is no treatment for that. As if that weren't enough, the older eye also reacts much more slowly to changes in light levels and — again due to the growing cloudiness of the lens — tends to scatter some of the light that does enter the eye.
The remedy is more and better light. Dr. Gilkes explained :
Added illumination on the object being looked at increases the amount of light available to, as it were, push its way past any impediments in the visual media such as early cataract or even to give added stimulation to an aging retina. The vast majority of older people who experience any kind of visual difficulty should use some form of the lighting system that delivers an adequate amount of light, that does not shine into their eyes and that can be deployed at a satisfactorily close range.Older, less efficient eyes, then, need more and better light to function. But they seldom get it.
The problem is that visual deterioration is so gradual that a person does not always realize that his eyes have changed, and we tend to take light for granted because it's all around us all the time. We humans feel we can adapt to anything in time, and it's true: we can adapt. But the error with respect to eyesight is that we adapt but our sensitivity and production are not the same.So we squint, or wrinkle our brows, or push our faces into the book we're reading, or pretend we've lost interest in the task we're attempting. We glumly accept a dimmer view of the world then we need to, without thinking about what we can do to improve our eyesight. Our eyes will serve us better if we give them the light they need.
Office workers need high-quality lightMuch of the research in this area has concentrated on the workplace rather than the home and is particularly relevant to millions of office workers aged 45 and above. These administrative, clerical and sales workers are doubly at risk: their eyesight is deteriorating, and they are required to concentrate on detailed visual tasks in artificially lighted environments. For them, proper illumination is of the utmost concern.
Several studies have shown that middle-aged workers need more light than their younger co-workers. And the contrast between their immediate work site and the background must be high. An Ohio State University study found that 30- to 40-year-olds need 17 percent more contrast to see an object as clearly as 20- to 30-year-olds, and that those in the 60 to 70 age bracket need 2 ½ times as much contrast to see as well as the younger group (Journal of the Illuminating Engineering Society).
The quality of available light is just as important as the quantity, according to Dr. Hughes. High-quality light, he says, must be sufficient to illuminate the area or task in question and should not emanate from the 'offending glare zone', which is 'that area in the ceiling where a light source will produce "veiling reflections. "
'If a light is directly above and in front of an office worker, for example, it will hit the work surface and bounce right up into his or her eyes,' Dr. Hughes explains. 'It produces a haze or veil of glare over the work.'
Since older workers are particularly vulnerable to glare, veiling reflections cause them more problems. Fatigue and low productivity can result, even though the worker may not be consciously aware of the glare.
Windows can cause direct glare or play havoc with an older person's ability to adapt to varying light levels. An expanse of glass invites a desk-bound worker to gaze at the out-of-doors, Dr. Hughes explains, but
if the ratio of brightness between the window and the desk or work area is too high, the light causes their pupils to constrict. Then, when they look back down, there's less light and their eyes dilate.This back-and-forth adaptation, particularly for older persons, whose eyes are slower to react, can cause fatigue. And modern offices make liberal use of glass. 'I've been in offices where people face glass windows all day,' he says. 'The brightness can be overwhelming, or at the very least, highly fatiguing, particularly over an eight-hour day. '
Dr. Hughes recommends a simple test to determine if a light source is in the 'offending zone'. Place a mirror on the table or desk at which you work. If you can see a light source in that mirror when you are seated normally, the light source is in the offending zone. To avoid glare and veiling reflection, move the work surface.
Lighting in the homeWhat about lighting in your own home? 'It's often quite difficult to evaluate the home environment,' Dr. Hughes continues. 'One thing to look for are bright areas which cause you to blink, squint or turn away. That probably means there's a bright window or a surface that's too highly reflective. Also, most glare in the home comes from a light bulb that's not properly shaded. '
A classic and dangerous example of harmful high-contrast transition is a dark stairwell at the end of a well-lighted hall found in many homes. Overhead fixtures in the offending glare zone can make kitchens particularly bad.
'I would say, though, that there is usually not enough light in the home,' Dr. Hughes hastens to add. 'One way to correct that is to paint walls in lighter shades to reflect more light. '
Another aspect of lighting quality is spectral power distribution, which is fancy talk for the nature of the light itself. Sunlight contains the full spectrum of light from infrared to ultraviolet, in a definite ratio. Most artificial light is different and hence produces a different effect in our eyes. Cool white fluorescent light, which is high in yellow-green light, tends to wash out colors and reduce perceived visual clarity. The new full-spectrum fluorescents nearly duplicate sunlight and render colors faithfully.
Understanding and accepting the fact that your eyes may change with age can be painful, but you can apply that understanding to making the most of what you have got. Begin by taking a closer look at your home. Do you have enough light, and is it placed effectively?
Dr. Gilkes cites the 'inverse square law' of illumination, which states that the amount of light falling on a surface varies both with the power of the light source and the distance the light must travel. In other words, moving a 25-watt bulb from eight feet away to four feet is the equivalent of replacing it with a 100-watt light bulb. 'Whenever inadequate or deficient lighting is suspected of forming part of an individual incapacity,' he wrote, 'the simple measure of bringing the light nearer will in many cases produce an increase in vision totally out of proportion to the simplicity of the solution. ' So if you have trouble reading, move the light closer. And keep it behind and to the left of you, to avoid veiling reflections.
Don't think that you can't afford good light. A typical household fixture fitted with a 100-watt bulb costs only a tiny amount more to operate for an entire year than the same fixture with a 60-watt bulb. Save energy when you can, but don't shortchange your eyes. Light placement is crucial, so beware of poorly placed fixtures. Is there a dangerously dark spot at the top of your stairs?
Take a look at your windows, too. Do they cause you to squint or turn your head? Perhaps you need new curtains or shades. Are the appliances and working surfaces in your kitchen blinding you with reflected light? Maybe you should change the light source or reduce the reflectivity of the surfaces.
Remember that your eyes run on light, just as your car runs on petrol. If you're having any problems seeing, see to your environment as well as your eyes. For more information, see entries on specific eye ailments.
How to Solve Vision Problems Naturally Reviewed by Healthy Kite on 9/02/2016 Rating: