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Maintaining Basic Equipment

Amateur astronomer’s eyes are their basic optical instruments. Articles abound on telescope optics maintenance, but fingers on one hand are enough to count articles on eye maintenance. More importantly, few, if any, articles are written on preventing the most common eye problems.


Visual Problems to Avoid
By age 65, over 22 percent will have definite evidence of cataracts, common eye-lens clouding. A similar percentage, albeit not always the same people, evidence “low” vision, and a smaller group will show beginnings of macular degeneration.


A brief description will clarify common preventable problems.

Diagram of eyeCataracts: The eye lens slowly becomes cloudy and eventually opaque. Cataracts involve oxidation of the clear, transparent lens proteins. They are correlated with excess exposure to ultraviolet light, so always wear dark glasses in the sun. Cataracts are accelerated by smoke, smoking, volatile solvents, and mostly by poor dietary habits, specifically inadequate amounts and varieties of vegetables and fruits.

Low vision: Low vision simply means that things look dimmer than they really are. The contrast of extended objects also suffers markedly, especially in dim light. Low vision means you lose a magnitude or so when looking at the stars or can’t see subtle details on planets. Low vision occurs in the eye retina, a very highly specialized nerve tissue that is an extension of brain tissue. Yes, it is your brain’s window on the world.

Macular degeneration: A small area on the retina, the macula, is responsible for focusing the eye. As it deteriorates, the ability to focus is lost and eventually everything becomes a blur.


Demographic Evidence Tells the Story
Over four decades ago, scientists noticed that cataract development correlated with geographic location, lifestyle, and food habits. Cataracts occur most where the sun is brightest and the upper atmosphere ozone the lowest. In short, ultraviolet light hitting the eye lens is the root cause. People whose diets are poorest in vegetables and fruits, especially those rich in vitamins C and E and bioflavonoids, have the highest rates of cataracts everywhere. Confirming studies abound.
Confirmation also comes from the antioxidant composition of the eye. The eye lens contains about 50 times the vitamin-C and about 35 times the vitamin-E concentrations found in normal blood. We may ask, “Why would nature expend the energy necessary to maintain those very high levels if they didn’t have a survival value?”

Similarly, all tissues are rich in two specific bioflavonoids, lutein and zeaxanthine. Most experts recommend about 14 milligrams of each daily. The best sources of lutein and zeaxanthine are kale, greens, spinach and broccoli. Your mother was right when she told you to eat your vegetables. You can deduce that the major protector substances in the eye are obtained from fruits and vegetables. In short, maintaining good vision requires good relations with the vegetable kingdom.
It is one more reason why nutritionists say you need at least three servings of vegetables daily, including one leafy (e.g., spinach) and one cruciferous (e.g., broccoli). I strongly recommend 5 veggies and 4 fruit servings daily.

When you cook vegetables you get about three times as much from them in nutritional value; especially with the antioxidants. I know that goes against what most people believe, but people used to believe the world was flat. It’s always better to eat cooked vegetables than raw. Just don’t cook them to soft, but to a point where they are still crisp.While not a single study has supported the notion that a pill providing lutein and zeaxanthine prevents cataracts, a number of excellent studies have proven that taking vitamins C and E daily, in a multiple vitamin-mineral supplement or separately, has a definite preventive effect. So, eat your oranges and drink orange juice, but take a basic supplement for insurance.


Macular Degeneration
Our parents (genetics) have a major role in everything and macular degeneration is no exception. However, genetics aside, dietary factors do have a role here. Think of the retina (including the macula) as brain tissue, and indirect evidence starts falling into place. One major chemical component of brain tissue is an omega-3 oil, docosahexaenoic acid, DHA, for short. The protection of DHA is also another role for vitamin E.

Indeed, DHA, when seriously short through oxidative destruction, and especially through poor dietary habits, increases the risk of macular degeneration and low vision. Similarly, a serious and prolonged vitamin-E deficiency has a similar effect. So, it is good news that we have a handle on several significant, interrelated causative factors. However, subsequent research on low vision has proven that restoring these substances, so vision is restored, requires about two years to achieve normalcy—that is only when the problem hasn’t reached the point where the condition is irreversible. Whenever there is a problem involving nerve tissue, especially brain tissue, damage can occur quickly, but improvement always moves in slow motion. Both macular degeneration and low vision prove that point quite clearly. Prevention, as always, is the best and most effective medicine. One last point about macular degeneration is that somehow zinc deficiency is involved, providing another reason to take a daily multiple vitamin-mineral supplement.

DHA is one of three omega-3 oils that are essential for health. We obtain these oils from cold-water (blue skinned) fin fish, such as tuna and salmon, and very few modern vegetables. Indeed, the only good modern vegetable source is flax seed; however, some nuts, such as walnuts, and a few oils, such as canola oil, are helpful. Omega-3 oils have a significant role in preventing inflammatory diseases (e.g., rheumatoid arthritis, Crohn’s disease) and heart disease. I put a tablespoon of flax oil on my daily bowl of high fiber cereal that I eat with soy beverage to increase my antioxidants—it’s an inexpensive, preventive, daily ritual supported by a very large body of research.


It’s About Antioxidants
When we say damage is caused by oxidation, we could use the modern buzzwords, free radicals. These are atoms or molecules in a stage where an electron is "free" to link to an oxygen atom. Every oxidative process, from rust to lung cancer and a lit match, has a free radical as its very earliest step. Think of a free radical reaction as a miniature explosion that occurs in nanoseconds. Visualize the antioxidants as nature's demolition teams that neutralize the free radicals before they can do any damage.

Although free radicals are the cost of breathing oxygen, nature seems to have anticipated the problem and provides an abundance of protective antioxidants. Fruits, vegetables, grains, and cereals are rich in the antioxidants.

The chart shows graphically the relative antioxidant delivery of some common foods. An excellent, “no brainer” way to start any day is a whole-grain, high-fiber cereal topped with blueberries (frozen is fine), soy beverage, and a tablespoon of flax oil, a glass of orange juice (vitamin C), and half a grapefruit (more vitamin C) or other fruit.

Eat lots of fruits and vegetables during the day. When you choose wine, make it a red wine, as it has most of the antioxidants found in red grapes.


Color on Your Plate
An “old wive’s tale” teaches that we should always have color (vegetables) on our plate. This teaching, which I traced to the 15th century, focused on the prevention of cancer, but it also guaranteed adequate vitamin A, which is responsible for general tissue health, night vision, and healthy eye tissue, especially the cornea. Indeed, most blindness in second- and third-world countries occurs because children don’t get sufficient daily amounts of vitamin A, as beta-carotene, from even a small carrot. Think of this: the cost of a single cruise missile could prevent all that blindness with some money left over. The simplest, most healthful snack available is baby carrots, which are readily available in small packs in supermarkets, food outlets, and even airports.

About The Author
Jim Scala is a member of EAS and is the president of the Mt. Diablo Astronomical Society. He is a biochemist with degrees from Columbia (B.A.) and Cornell (Ph.D.) Universities, and post-doctoral studies at Harvard University. In addition to research and teaching, he is the author of 14 books on nutrition. With that career coming to a close, he passionately pursues astronomy, especially CCD astronomy, from his backyard observatory in Lafayette. He welcomes visitors to the La Scala observatory.



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