Obesity is a chronic, recurring, complex disorder characterized by excess body weight.
Although genetics and some disorders cause obesity, most adolescent obesity results from a lack of physical activity and consuming more calories than needed for activity level.
A body mass index (BMI) at or over the 95th percentile for age and gender is one tool that is used to diagnose obesity.
Eating a nutritious diet and increasing exercise help treat obesity, and some children may be given medication for weight loss or undergo weight-loss surgery.
Obesity has become more common among adolescents, and approximately 1 in 5 adolescents in the United States has obesity. Although most of the complications of obesity occur in adulthood, adolescents with obesity are more likely than their peers to have high blood pressure and type 2 diabetes. Most adolescents with obesity become adults with obesity.
Because of society’s stigma against obesity, many adolescents with obesity are teased or bullied, which can cause them to become increasingly sedentary and socially isolated.
(See also Introduction to Health Care Issues in Adolescents and Obesity in adults.)
Causes of Obesity in Adolescents
Many environmental factors contribute to obesity in adolescents. For example, adolescents may have too much access to unhealthy foods and not enough access to healthy foods, they may have a sleep disorder, or they may develop sedentary habits as a result of overuse of cellphones, computer and console games, and other electronic devices.
Hormonal disorders, such as an underactive thyroid gland (hypothyroidism) or overactive adrenal glands, may result in obesity but are rarely the cause. Adolescents with weight gain caused by a hormonal disorder usually have other signs of the underlying disorder.
Genetics seem to play a major role, which means that some people are at greater risk of obesity than others, and obesity may be more common among members of the same family.
Diagnosis of Obesity in Adolescents
Body mass index
Sometimes testing for other disorders
Body mass index (BMI) is one tool that is used to diagnose obesity. Adolescents whose BMI is in the top 5% for their age and gender are considered to have obesity. Being in the top 5% means their BMI is higher than 95% of their peers (at or over the 95th percentile). However, BMI has limitations because it does not take into account muscle mass, bone density, overall body composition, and racial and sex differences.
Any adolescent with obesity who is short and has high blood pressure may be tested for the hormonal disorder Cushing syndrome. Other tests are done if doctors suspect an adolescent has another disorder or another disorder has been diagnosed, such as diabetes, high blood pressure, high levels of fats in the blood, and mental health disorders.
Treatment of Obesity in Adolescents
Healthy eating and exercise habits
For adolescents 12 years old and older with a BMI at or over the 95th percentile, weight-loss medications
For adolescents 13 years old and older with a BMI significantly over the 95th percentile, evaluation for weight-loss surgery
All children and adolescents with obesity are given intensive strategies to help them develop healthy eating and exercise habits and make changes to their health behavior.
Reducing calorie intake and burning calories are 2 ways to meet these goals.
Calorie intake is reduced by
Establishing a well-balanced diet of ordinary foods
Making permanent changes in eating habits
Calorie burning is increased by
Increasing physical activity
Adolescents 12 years old and older with obesity (BMI at or over the 95th percentile for age and gender) may be offered medications for weight loss.
Adolescents 13 years old and older with severe obesity (BMI significantly above the 95th percentile for age and gender) may be referred to a surgeon who specializes in this area for a full evaluation for weight-loss surgery (bariatric surgery).
Counseling to help adolescents cope with social problems may be helpful.
