Iron: Essential for healthy blood cells, iron becomes especially important when girls begin to menstruate. With each period, a woman loses small amounts of iron. “About 10% of American women are iron deficient,” says Dorothy Klimis-Zacas, PhD, a professor of nutrition at the University of Maine and co-editor of Nutritional Concerns of Women (CRC Press, 2003). “About 5% have iron deficiency anemia.” Symptoms of low iron include fatigue, impaired immunity, and poor performance at school or work.
Not everyone who is underweight suffers from an eating disorder, but anorexia and bulimia are serious health problems in this country; an estimated 500,000 women suffer from anorexia, and 1 to 2 million women struggle with bulimia. Women with anorexia nervosa starve themselves and/or exercise excessively, losing anywhere from 15 percent to 60 percent of their normal body weight. Some die. Women with bulimia nervosa binge on large quantities of food—up to 20,000 calories at one time—and then try to get rid of the excess calories. Some purge by inducing vomiting, abusing laxatives and diuretics or by taking enemas. Others fast or exercise to extremes.
Most experts recommend 1,300 mg of calcium a day for girls aged 9 through 19. Natural sources of calcium, such as low-fat dairy products, are the smartest choice, because they also contain vitamin D and protein, both required for calcium absorption. Milk, yogurt, and cheese contribute most of the calcium in our diets. Some vegetables are also good sources, including broccoli, kale, and Chinese cabbage. Many foods are supplemented with calcium, including some brands of orange juice and tofu. The daily intake for Vitamin D is 600 IU per day for most children and healthy adults.
Although growing bodies need plenty of energy in the form of calories, many children and teenagers consume way too many, says Ruth Frechman, RD, a spokesperson for the American Dietetic Association. The latest findings from federal surveys show that 18% of adolescents and teenagers are fatter than they should be. Kids who are obese are 16 times more likely than healthy weight children to become obese as adults, other findings show.
In the past, women have often tried to make up deficits in their diet though the use of vitamins and supplements. However, while supplements can be a useful safeguard against occasional nutrient shortfalls, they can’t compensate for an unbalanced or unhealthy diet. To ensure you get all the nutrients you need from the food you eat, try to aim for a diet rich in fruit, vegetables, quality protein, healthy fats, and low in processed, fried, and sugary foods.