When the crystalline lens loses transparency and opaque areas increase, we are dealing with a phenomenon called cataracts.
According to various statistic, almost two-thirds of people in their sixties develop an onset of cataract. In the United States, 1.35 million operations are performed each year.
Cataracts usually develop in both eyes, but at different rates, so you often find yourself with one eye seeing better and one seeing worse.
Cataracts are caused by multiple harmful environmental factors (free radicals). Injuries to the eyes can cause cataracts at any age.
A severe contusion, a puncture wound, a cut, exposure to excessive heat or chemical corrosion can damage the crystalline lens and cause what is known as a traumatic cataract.
Opacity of the lens can also be due to infection, certain medications or diseases such as diabetes, which can produce secondary cataracts.
Photosensitizing drugs accentuate the damage to the crystalline lens caused by light and oxidative processes initiated by free radicals.
Medications, cholesterol-lowering drugs, antibiotics, and diuretics are all frequently used photosensitive substances.
There are at least 200 prescription drugs that are known to promote or cause cataracts.
Even in children, cataracts can occur as a result of steroid therapy.
Smoking itself can contribute to opacification of the crystalline lens. Some researchers even claim that quitting smoking reduces the risk of cataracts by 25%.
At an experimental level, it is possible to induce cataracts simply by exposing your eye to an environment with a high oxygen content, such as that in which hyperbaric oxygen therapy is carried out.
Animal tests leave no doubt: there is a relationship between high oxygen content and cataracts
Priestley (1775), the discoverer of oxygen, observed that vital processes accelerate if atmospheric oxygen is replaced by pure oxygen, apparently because of the greater oxidative capacity of the latter.
In the process of transformation of oxygen into water, hydrogen peroxide is produced, then carbon dioxide and superoxide anions. In other words, the oxygen molecule is transformed into superoxide, a highly reactive free radical, which initiates an oxidation process and can damage tissues.
Once reached the ocular tissues, the aqueous humor or the crystalline lens, even small amounts of photo-sensitizing substances can lead to a continuous production of O2 and its derivatives H2O2 and OH.
Every time the eyelids are lifted, light penetrates the eyes, causing oxidative processes.
In most cases everything originates from a damage to the cell membranes of the epithelium, which are directly exposed to the fluids of the eye. The free radicals produced diffuse with the fluid that surrounds the crystalline lens.
The main aim is therefore to prevent or at least minimize damage to the cell membrane.
If the cataract is located on the peripheral areas of the crystalline lens, it is possible that vision is not affected. The opacification of the central zone, however, impairs normal vision.
Frequent symptoms of cataracts are blurred or double vision, increased sensitivity to light and less vivid color perception. The pupil, which normally appears black, may change color to yellowish or white.
When cataracts begin to seriously impair vision, they are usually removed by a simple surgical procedure during which an artificial lens is often inserted.
Some people will need to wear contact lenses or glasses, but will still be able to see well.
However, there are more and more cases in which it is not possible to operate because the patient has already undergone laser surgery.
Compared to other parts of the body, ocular tissue and eye fluids contain a very high concentration of vitamin C (ascorbic acid).
|Ascorbic acid content in tissue||Quantity mg/Kg|
Due to the active transport of ascorbic acid from plasma across the blood-ocular barrier, the concentration of vitamin C in the aqueous humor is always about twenty times higher than in other parts of the body.
These were their conclusions (The Nutrition Desk Reference, 1995, p.85):
One study found that administration of supplemental doses of vitamin C over a long period can reduce the risk of cataracts by as much as 45%.
In another research, we compared antioxidant intake in cataract patients and a healthy control group and found that the former took much less vitamin C and vitamin E.
Compared to the others, this study also found that antioxidant administration reduced the risk of cataracts by 50 percent
Research conducted at Tuft University in 1994 also suggests that taking high doses of vitamin C over a long period can significantly decrease the risk of cataracts in women.
It hypothesizes that there is a link between taking vitamin C over a 10-year period and a 77% lower rate of cataracts, as well as an 84% lower rate of average opacification in all areas of the lens than in women who did not take vitamin C supplements.
The conclusion is that vitamin C reduces the risk of getting cataracts because it has an antioxidant effect.
It can also protect your eye from sun damage. According to the Tuft University study, the best results were seen in women who took 400 to 800 mg of vitamin C daily.
So make sure you’re getting enough of it.
According to another research, published in 1991 in the American Journal of Clinical Nutrition, there is a link between low levels of carotenoids (vitamin A precursors) and vitamin C and high risk of cataracts.
A similar work, published in 1992 in the British Journal of Medicine, examined for eight years the effects of vegetable consumption on the occurrence of cataracts in over 50,000 women.
The result was that the risk of cataract formation could be decreased by 50% by eating 5 servings of spinach per week.
An epidemiological study conducted over a 5 years period determined that the risk of cataracts decreased by up to 50% by giving vitamin E alone. Vitamin B12, vitamin B5, selenium and glutathione are also effective in fighting free radicals.
Glutathione, a substance that plays a key role in the formation of enzymes necessary to protect against damage caused by free radicals, is very useful in preventing the onset of cataracts.
Several studies have shown that lens patients with cataracts all have a reduced level of glutathione (1/15th of normal) while the level of vitamin C was 10 times lower than normal.
Originally it was thought that these deficiencies were caused by the lens becoming darker, but now it is believed that the decrease in antioxidants is prior to the onset of cataract.
A component useful to the crystalline lens, is found in eggs, garlic, avocado, asparagus, onions and red meat. Your diet should include foods containing sulfur or cystine, which are useful in stimulating the production of glutathione in your body.
Vitamin B5 seems to delay the aggregation of proteins in the crystalline lens and is also available on the market in spray form.
All the studies mentioned show that your diet is extremely important in preventing cataracts. We know that unfortunately the modern lifestyle does not help to keep a complete diet. As a result, don’t forget to use nutritional supplements if you need to.
The list below will help you understand what you need to minimize your risk of cataracts.
Here are a number of foods that are very helpful against cataracts: amazonian nuts, carrots, turmeric, sunflower seeds and onions:
|Recommended nutritional supplements||Quantity|
|Vitamin A||10,000 units per day|
|Vitamin B||1000mg per day|
|Vitamin C||500mg per day|
|Vitamin E||400-800 units per day|
|Magnesium||500 mg per day|
|Selenium||100 mg per day|
|Zinc||30 mg per day|
|Manganese||5 mg per day (Inhibits cataract development)|
Quitting smoking and not overdoing medications are helpful behaviors. Avoid cooked dairy products, saturated fats and all fats and oils that have been heated. They promote the formation of free radicals. Use only cold-pressed vegetable oils.
Also avoid antihistamines and limit sugar consumption as much as possible.
If you have any doubts, always remember to consult a specialized doctor or your eye doctor of choice. Do not replace his opinion with something not effective.
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