Vitamin A toxicity comes from the large doses in pills, not from the carrots and green vegetables. In the older child and adult it begins, as do most vitamin toxicities, as a very slow, gradual process that is almost not noticed. Initially, the skin becomes dry and coarse and some hair is lost. The fingernails become thickened and less well-attached to their under-surface. The bones become thickened, fatigue sets in, and there may be some low-grade fevers and mental changes. Eventually, if the high doses of vitamin A are kept up for a long period of time a liver disease (commonly called ‘polar bear liver’ because of its presence in Arctic explorers who were eating large quantities of whale blubber) develops and produces a situation similar to alcoholic cirrhosis.
In young children, the effects are even more devastating. Appetite diminishes and weight gain decreases. The child becomes increasingly irritable and has tender bones. Despite his irritability, he does not wish to be picked up because those bones hurt. Some of the irritability may be due to increased pressure within skull. This may also cause an enlargement of the skull, or may even a mimic a brain tumor.
Thus children who are given large quantities of vitamin A to prevent colds or acne are at risk for sever problems, and perhaps even more so if the vitamin A is administered in an emulsified form. For this reason, stick to levels that are near the RDA, if supplementation is needed at all. And remember, supplementation is usually not needed. Milk is fortified with vitamin A, and leafy green plants, animal meats and fresh water fish usually meet everyone’s needs without deficiency.
In young children, the effects are even more devastating. Appetite diminishes and weight gain decreases. The child becomes increasingly irritable and has tender bones. Despite his irritability, he does not wish to be picked up because those bones hurt. Some of the irritability may be due to increased pressure within skull. This may also cause an enlargement of the skull, or may even a mimic a brain tumor.
Thus children who are given large quantities of vitamin A to prevent colds or acne are at risk for sever problems, and perhaps even more so if the vitamin A is administered in an emulsified form. For this reason, stick to levels that are near the RDA, if supplementation is needed at all. And remember, supplementation is usually not needed. Milk is fortified with vitamin A, and leafy green plants, animal meats and fresh water fish usually meet everyone’s needs without deficiency.
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