The cornea is a clear dome that protects the surface of the eye. Damage to the cornea can seriously affect vision. In severe cases, damage to the cornea is so severe that corneal transplant becomes necessary. Some, but not all, of the disease processes that cause corneal ulceration can be helped by dietary changes.
Causes
One of the most common causes of corneal ulceration and blindness worldwide is vitamin A deficiency. Dry eye syndrome, when the cornea becomes dry, fragile and easily scratched or irritated, can also lead to corneal ulcerations. Determining the cause of corneal ulcerations helps determine which dietary treatment might improve the condition.
Omega-3 Fatty Acids
Some cases of dry eye improve when you increase your intake of flaxseed or fish oil, both of which contain omega-3 fatty acids. Salmon, tuna, halibut and sablefish are high in omega-3 fatty acids. Flaxseed can be sprinkled on foods to increase omega-3 intake. The type of omega-3 fatty acid in flaxseed may be less effective in decreasing dry eye than the omega-3 fatty acids found in fish. The flaxseed form of omega-3 fatty acid, ALA, must convert to EPA and DHA, the forms found in fish oil. However, flaxseed is a good choice if you follow a vegetarian diet.
Fruits and Vegetables
Vitamin A deficiency occurs in people who don't consume enough carotenoids, found in leafy green vegetables and yellow vegetables such as pumpkin and squash as well as brightly colored fruits such as oranges or papayas. Increasing intake of these fruits and vegetables helps treat and prevent vitamin A deficiency; vitamin A supplementation will probably also be required for treating existing disease.
Other Fats
Vitamin A deficiency may also occur in people who have trouble with fat absorption, since fats are required for vitamin A absorption. Increasing fruit and vegetable intake and adding vitamin A-fortified cereals and milk, liver, egg yolks and fish liver oils help prevent vitamin A deficiency, according to The Merck Manuals Online Medical Library. Treating deficiency will also require vitamin A supplementation.
Caveats
Vitamin A can be toxic if consumed in excessive amounts. This is unlikely to happen from dietary sources, with two exceptions. Polar bear and seal livers contain extremely high amounts of vitamin A and could cause toxicity.
