Obesity in children has increased in recent decades. Behavioral and environmental factors are primarily responsible, although genes play an important role in regulation of body weight.
Calculating body mass index (BMI) is the most widely accepted method of screening for obesity in children. Abnormal BMI cutoffs in children are determined by age- and sex-specific percentiles.
Impaired glucose tolerance and type 2 diabetes mellitus are prevalent in children with obesity.
Preventing excessive weight gain in children is of paramount importance in confronting the obesity epidemic, as obesity is difficult to treat at all ages, and obese children tend to become obese adults.
The mainstay of treatment is lifestyle modification to improve diet and increase physical activity. Pharmacotherapy and bariatric surgery may be considered as an adjunct to lifestyle modification in severely obese adolescents.
Obesity is a condition of excessive body fat or adiposity that exceeds healthy limits.
The most widely accepted method to screen for excess adiposity is calculation of body mass index (BMI). Abnormal BMI cutoffs in children are determined by age- and sex-specific percentiles based on the Centers for Disease Control and Prevention 2000 growth charts, as the amount of body fat changes with age and differs between boys and girls.
For children under 2 years of age, BMI percentiles are not available; thus, obesity is defined as a weight ≥95th percentile for height.
History and exam
Key diagnostic factors
- body mass index (BMI) ≥95th percentile
- weight ≥95th percentile for height
Other diagnostic factors
- increased waist-hip ratio
- obese parents
- rapid weight gain in infancy
- weight gain in early childhood
- non-Hispanic black or Hispanic ethnicity
- poor socioeconomic status
- sedentary lifestyle
- intrauterine growth restriction
- maternal gestational diabetes
- diet high in energy-dense foods, fast foods, and high-sugar beverages
- screen time >2-3 hours/day
- sleep deprivation
- exposure to corticosteroids, antibiotics, or acid-suppressing medication
Investigations to consider
- fasting blood glucose
- serum lipids
- liver function tests
- bioelectric impedance analysis
- abdominal CT or MRI
body mass index (BMI) ≥85th to 94th percentile (overweight)
BMI ≥95th percentile and <120% of 95th percentile (class 1 obesity)
BMI ≥120% of 95th percentile (class 2 and class 3 obesity)
Dianne Deplewski, MD
Associate Professor of Pediatrics
Section of Adult and Pediatric Endocrinology
Pediatric Endocrinology Fellowship Program
University of Chicago
DD declares that she has no competing interests.
Steven S. Rothenberg, MD
Chief of Pediatric Surgery
The Mother and Child Hospital
Associate Clinical Professor of Surgery
University of Colorado
SSR declares that he has no competing interests.
Seema Kumar, MD
Assistant Professor of Pediatrics
SK declares that she has no competing interests.
Peter Bundred, MBBS, MD
Honorary Research Fellow
Department of Health Services Research
Institute of Psychology, Health and Society
University of Liverpool
PB declares that he has no competing interests.
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