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Obesity in Adolescents

By

Sharon Levy

, MD, MPH, Harvard Medical School

Reviewed/Revised Jul 2022
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Obesity is now twice as common among adolescents than it was 30 years ago and is one of the most common reasons for visits to adolescent clinics. Although fewer than one third of adults with obesity were obese as adolescents, most adolescents with obesity remain obese in adulthood.

Despite many therapeutic approaches, obesity is one of the most difficult problems to treat, and long-term success rates remain low.

Although most of the complications of obesity Obesity Obesity is a chronic, multifactorial, relapsing disorder characterized by excess body weight and defined as a body mass index (BMI) of ≥ 30 kg/m2. Complications include cardiovascular disorders... read more occur in adulthood, adolescents with obesity are more likely than their peers to have high blood pressure. Type 2 diabetes mellitus Diabetes Mellitus in Children and Adolescents Diabetes mellitus involves absence of insulin secretion (type 1) or peripheral insulin resistance (type 2), causing hyperglycemia. Early symptoms are related to hyperglycemia and include polydipsia... read more is occurring with increasing frequency in adolescents due to insulin resistance related to obesity. Because of society’s stigma against obesity, many adolescents with obesity have a poor self-image and become increasingly sedentary and socially isolated.

Etiology of Obesity in Adolescents

The factors that influence obesity among adolescents are the same as those among adults. Most cases are external (eg, consuming too many calories and/or a low-quality diet), often in conjunction with a sedentary lifestyle. Genetic influences are common, and responsible genes are now being identified ( see also Obesity and the Metabolic Syndrome Obesity and the Metabolic Syndrome ).

Parents may be concerned that obesity is the result of some type of endocrine disease, such as hypothyroidism Hypothyroidism Hypothyroidism is thyroid hormone deficiency. Symptoms include cold intolerance, fatigue, and weight gain. Signs may include a typical facial appearance, hoarse slow speech, and dry skin. Diagnosis... read more Hypothyroidism or hyperadrenocorticism, but such disorders are rarely the cause. Adolescents with weight gain caused by endocrine disorders are usually of small stature and have other signs of the underlying disorder.

Diagnosis of Obesity in Adolescents

  • Body mass index

Determination of the body mass index Diagnosis Obesity is a chronic, multifactorial, relapsing disorder characterized by excess body weight and defined as a body mass index (BMI) of ≥ 30 kg/m2. Complications include cardiovascular disorders... read more (BMI) is an important aspect of physical assessment. Adolescents whose BMI is ≥ the 95th percentile for their age and sex are considered to have obesity.

Primary endocrine (eg, hyperadrenocorticism, hypothyroidism) or metabolic causes are uncommon but should be ruled out if height growth slows significantly. If the child is short and has hypertension, Cushing syndrome Cushing Syndrome Cushing syndrome is a constellation of clinical abnormalities caused by chronic high blood levels of cortisol or related corticosteroids. Cushing disease is Cushing syndrome that results from... read more Cushing Syndrome should be considered.

Treatment of Obesity in Adolescents

  • Behavior and lifestyle interventions

  • For adolescents 12 years old and older with a BMI ≥ the 95th percentile, weight-loss medications

  • For adolescents 13 years old and older with a BMI ≥ 120% of the 95th percentile, evaluation for metabolic and bariatric surgery

All children and adolescents with obesity should be given intensive health and lifestyle change strategies that address nutrition, physical activity, and health behavior.

Adolescents 12 years old and older with obesity (BMI ≥ the 95th percentile for age and sex) may be given medications for weight loss (see the AAP’s guidelines on Use of Pharmacotherapy [2023]).

Adolescents 13 years old and older with severe obesity (BMI ≥ 120% of the 95th percentile for age and sex) may be referred for evaluation for metabolic and bariatric surgery (see the AAP’s guidelines on Pediatric Metabolic and Bariatric Surgery [2023]).

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

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