American Medical Association Family Medical Guide - American Medical Association [225]
Many teens have busy schedules that allow little time for nutritious meals. They find it easier to eat fast-food meals and processed snacks, which tend to be high in calories and fat. As a result, an increasing number of American teenagers are overweight and beginning to have many of the health problems associated with obesity—including type 2 diabetes (see page 894), high blood pressure (see page 574), and early signs of heart disease (see page 559). Parents have little control over their adolescent’s diet outside the home so they should stock up on nutritious snacks—such as fresh fruits and vegetables, low-fat yogurt and cheeses, and whole grains—and resist buying high-calorie processed foods.
Body Image
Being obsessed with their weight or appearance leads some girls, and an increasing number of boys, to develop eating disorders (see page 724) such as anorexia or bulimia. Some teens think they need to be thinner than they should be based on their body build and height. During adolescence, girls often start dieting to lose the additional fat that comes with puberty. Boys usually develop eating disorders as a result of a desire to succeed in sports or to meet a sport’s weight requirements. Most eating disorders start during adolescence. Having an eating disorder can lead to changes in the body’s metabolism, damage to internal organs, and skin and dental problems. Symptoms include fainting, anxiety, dry skin, and fine hair all over the body. In girls who have bulimia, scars may form on the hands or knuckles. Girls who become too thin can stop having menstrual periods.
Some teens (usually boys) will grow into their body and lose weight as they get taller. If a child is concerned about his or her weight or unsure what it should be, a doctor can evaluate it and determine whether the teen needs to lose weight. The doctor can work with him or her to develop a weight-loss plan (see page 53) and help the teen learn the basics of a healthy diet (see page 36).
Exercise
Along with overeating, lack of exercise is a major factor in the epidemic of obesity among young people in the United States. Only about one out of three American adolescents gets enough exercise. Many children spend more time sitting in front of a TV or computer than engaging in physical activities. Teens who play sports and are physically active are less likely than their less active peers to have medical problems such as diabetes and obesity. They are also less likely to smoke, drink, have an unplanned pregnancy, or commit suicide, possibly because exercise improves mood and lowers stress and anxiety. Organized sports have the added benefit of instilling discipline and teamwork and developing skills.
Weight-bearing exercise (such as walking, running, aerobics, and lifting light weights) makes bones strong and helps them take in the bone-building mineral calcium, which is especially important for adolescent girls. However, young people should not aggressively train with weights until their bodies are fully physically mature, usually between ages 15 and 18. Lifting weights that are too heavy and lifting incorrectly (for example, lifting the weights with a jerk, as professional power lifters do) can cause injuries. In addition, lifting weights that are too heavy can inhibit (rather than strengthen) bone growth in adolescents by putting pressure on still-growing bones.
A teen should pick a sport or physical activity that he or she enjoys. Interacting with people who have the same interests can help teens stick with an exercise program. The most successful activities are those that help them develop skills while having fun. Ideally, teens should try to exercise 6 days a week for at least 60 minutes, but any amount of exercise is better than none. Exercising longer and harder has additional health benefits. However, adolescent girls who exercise too much and eat too little can develop a disorder called female athlete triad (see