“TEENAGERS AND YOUNG adults need to be hit over the head with the calcium message,” says Christine Rosenbloom, Ph.D., associate professor of nutrition at Georgia State University in Atlanta. Between ages 11 and 17, kids gain 50 percent of their adult weight, and bones are rapidly growing longer and denser, on their way to peaking in density somewhere between ages 25 and 35 Rosenbloom says a great many high school and college-age girls diet constantly, depriving their bodies of the calcium that is so essential to creating strong bones that will resist crippling osteoporosis later on. At 1,200 ma. a day, the RDA for the 11-to-24 group is considerably higher than for older adults, and the National Institutes for Health would like to see that number increased to 1,500 mg. Besides the foods already mentioned for younger children, other good calcium sources include turnip greens, soybeans, kale and broccoli. (Cheese has plenty of calcium, but it’s also high in animal protein, which causes the body to excrete calcium.)
Rosenbloom says that while girls and young women often skimp on calcium, boys and young men are often deficient in vitamin A and its related antioxidant, beta carotene, which converts to vitamin A in the body. “Studies show low intakes of vitamin A in young men, who don’t get enough fruits and vegetables,” says Rosenbloom, who advises boys to eat at least a couple of daily servings of A-rich foods. Although most Americans consume much more protein than necessary, Rosenbloom says one group is at risk for deficiencies: high school and college-age girls, many of whom are weight-conscious–and many of whom try out vegetarianism. “Their idea of going vegetarian is to just increase their carbohydrates and delete animal products, but they don’t do anything else,” she says. “They don’t eat any legumes, or vegetables with protein, just fruit and pasta and vegetables like broccoli. Their main goal is to eat low-fat, not balanced.” She has these girls fill out food records and tabulate their own nutritional breakdowns, so they can discover deficiencies themselves. “I see more and more young women turning to vegetarianism,” she says, “but many of them need help to become informed vegetarians.”
To help teens stay the course through the years of junk food, diets and fad eating, Stewart strongly advises families to gather for one meal a day, to reinforce healthful eating habits and the pleasures of the table. Eating together regularly also can help parents watch out for signs of eating disorders, 76 percent of which appear between the ages of 11 and 20. Although a psychological illness more than a nutritional one, anorexia nervosa makes itself known at the dinner table. If your child is avoiding meal time, is intensely afraid of gaining weight, denies hunger, refuses to eat shows signs of abnormal weight loss; seek professional help.