Vitamin deficiencies

The good news is that vitamin deficiencies are rare among people who have access to a wide variety of foods and know how to put together a balanced diet. For example, the only people likely to experience a vitamin E deficiency are premature and/or low–birth weight infants and people with a metabolic disorder that keeps them from absorbing fat. A healthy adult may go as long as 10 years on a vitamin E–deficient diet without developing any signs of a problem. Aha, you say, but what’s this subclinical deficiency I hear so much about? Nutritionists use the term subclinical deficiency to describe a nutritional deficit not yet far enough advanced to produce obvious symptoms. In lay terms, however, the phrase has become a handy explanation for common but hard-to-pin-down symptoms such as fatigue, irritability, nervousness, emotional depression, allergies, and insomnia. And it’s a dandy way to increase the sale of nutritional supplements.
Simply put, the RDAs protect you against deficiency. If your odd symptoms linger even after you take reasonable amounts of vitamin supplements, probably something other than a lack of any one vitamin is to blame. Don’t wait until your patience or your bank account has been exhausted to find out. Get a second opinion as soon as you can. Table 10-2 lists the symptoms of various vitamin deficiencies.