Veggy diets run risk of deficiencies
A growing number of teenagers and college students are choosing a vegetarian or vegan diet. If you are making the switch, be aware that the new diet won't necessarily be more healthful just because it includes more fruits and vegetables. Though a balanced vegetarian diet can provide all essential nutrients, some nutritional pitfalls can have serious health consequences.
In general, vegetarian diets that include milk products are easier to balance. Make sure the daily diet includes at least three servings --1 cup of milk or yogurt or an ounce of hard cheese equals a serving.
For teens that avoid milk, find comparable sources of calcium, vitamins D, B-2, B-12 and protein. Properly fortified soymilk can be a reasonable option. Other fortified foods provide calcium, but those such as rice milk and orange juice are lower in protein and can lack other nutrients found in milk. It is also important to shake up calcium-fortified beverages because the added calcium often settles to the bottom.
Foods such as almonds, beans and spinach contain calcium in a form that is very poorly absorbed.
Iron intake among vegetarian teens can easily fall too low, especially among girls. The typical results are tiredness, learning problems, depression and even a predisposition to attention deficit hyperactivity disorder. A variety of nutrient deficiencies can affect brain function and emotions.
A vegetarian diet must provide almost twice as much iron as a meat-based diet because the iron is not absorbed as efficiently. Consequently, a multivitamin/mineral supplement with iron can be a good idea. The supplement also should contain zinc and vitamins B-2, B-12 and D.
The beneficial omega-3 fatty acids found in fish oils are also lacking in a typical vegetarian diet. Many nutritionists and dietitians recommend an algae oil supplement as a vegetarian source of these fatty acids. One of them, commonly called DHA, is a major component of the brain and supports normal brain development and function.
To maintain adequate protein intake, include a high-protein food at each meal. Choose the higher protein vegetarian meat alternatives that provide 10- to 15-grams of protein per serving.
A good vegetarian diet needs a variety of foods to provide all essential nutrients.
Alan Titchenal, Ph.D., C.N.S. and Joannie Dobbs, Ph.D., C.N.S. are
nutritionists in the Department of Human Nutrition, Food and Animal
Sciences, College of Tropical Agriculture and Human Resources, UH-Manoa.
Dr. Dobbs also works with the University Health Services and prepares
the nutritional analyses marked with an asterisk in this section.