Obesity in children

Last reviewed: 29 Aug 2023
Last updated: 30 Nov 2022



History and exam

Key diagnostic factors

  • body mass index (BMI) ≥95th percentile
  • weight ≥95th percentile for height
More key diagnostic factors

Other diagnostic factors

  • increased waist-hip ratio
  • hypertension
Other diagnostic factors

Risk factors

  • 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
  • urban environment
  • maternal smoking in pregnancy
More risk factors

Diagnostic investigations

Investigations to consider

  • fasting blood glucose
  • serum lipids
  • liver function tests
More investigations to consider

Emerging tests

  • DEXA
  • bioelectric impedance analysis
  • abdominal CT or MRI

Treatment algorithm


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

Program Director

Pediatric Endocrinology Fellowship Program

University of Chicago




DD declares that she has no competing interests.

Peer reviewers

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

Mayo Clinic




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.

  • Obesity in children images
  • Differentials

    • Primary hypothyroidism
    • Secondary hypothyroidism
    • Cushing syndrome
    More Differentials
  • Guidelines

    • Dietary guidelines for Americans, 2020-2025
    • Guidelines on physical activity and sedentary behaviour
    More Guidelines
  • Patient leaflets

    Weight problems in children: changing unhealthy habits

    Weight problems in children: improving a child's diet

    More Patient leaflets
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