Obesity affects as many as 30 percent of American children and adolescents, according the 2008 report by the American Academy of Children and Adolescent Psychiatry. Poor eating in childhood can lead to health problems including diabetes and even heart disease. Teenagers make many of their own food choices, such as snacks at the mall or meals at school. Because many of their options are unhealthy, teens need guidance on how to make wise food choices.

Nutrition

Teenage bodies need important nutrients to facilitate growth and development. They need a balanced diet with lean protein, low-fat dairy, fruits, vegetables and whole grains. Each meal should have several if not all forms of food from major food groups. In particular, teens need to continue to get the correct amounts of iron and calcium, which often doesn't happen as teens drink soda instead of milk. Moderately active teens girls should eat 1,600 to 2,000 calories and boys 1,800 to 2,400 calories a day. Teens need guidance about portion control so that they eat enough to gain the nutrition they need, but not overeat or under-eat.

Family Diet

Healthy eating should not be for teens alone. Parents need to model a healthy lifestyle by eating and serving nutritional foods. Families should eat at least one meal together a day, which not only teaches teens proper diet, but also can lead to improved grades and a lower risk of drug use. Encourage your teens to participate in meal planning and preparation so they can learn about cooking and nutrition.

Reduce Junk Food

Given the choice, teens gravitate to unhealthy food items such as french fries and soda. Eliminate or reduce fattening and sugary foods, and replace them with healthier options such as fruit. Provide high-protein breakfast options instead of breakfast bars that are high in sugar and low on nutrition. Encourage your teen to pack a lunch or make healthy lunch choices at school instead of eating fries and pizza. Make junk food a special treat instead of part of everyday eating.

Self-Esteem and Eating

Self-esteem, depression and body dissatisfaction can impact teenage eating. The U.S. Department of Health and Human Services reports that 30 percent of girls and 16 percent of boys in high school suffer from eating disorders such as anorexia, bulimia and binge eating. These extreme diet tactics can lead to nutritional deficiencies and damage to vital organs and, in severe cases, the brain. Further, teenage girls who diet are 324 percent more likely to become obese than girls who don't diet. A healthy diet and moderate exercise help control weight, but also provide important nutrients and improve self-esteem.