title: The Quételet index revisited in children and adults.
abstract: BACKGROUND
  The body mass index (BMI) is based on the original concept that body weight increases as a function of height squared. As an indicator of obesity the modern BMI assumption postulates that adiposity also increases as a function of height in states of positive energy balance.
  
  
  OBJECTIVE
  To evaluate the BMI concept across different adiposity magnitudes, in both children and adults.
  
  
  METHODS
  We studied 975 individuals who underwent anthropometric evaluation: 474 children and 501 adults. Tetrapolar bioimpedance analysis was used to assess body fat and lean mass.
  
  
  RESULTS
  BMI significantly correlated with percentage of body fat (%BF; children: r=0.893; adults: r=0.878) and with total fat mass (children: r=0.967; adults: r=0.953). In children, body weight, fat mass, %BF and waist circumference progressively increased as a function of height squared. In adults body weight increased as a function of height squared, but %BF actually decreased with increasing height both in men (r=-0.406; p<0.001) and women (r=-0.413; p<0.001). Most of the BMI variance in adults was explained by a positive correlation of total lean mass with height squared (r(2)=0.709), and by a negative correlation of BMI with total fat mass (r=-0.193).
  
  
  CONCLUSIONS
  Body weight increases as a function of height squared. However, adiposity progressively increases as a function of height only in children. BMI is not an ideal indicator of obesity in adults since it is significantly influenced by the lean mass, even in obese individuals.
authors.affiliation: Department of Internal Medicine, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Mexico. Electronic address: erwinchiquete@hotmail.com.
authors.forename: Erwin
authors.initials: E
authors.lastname: Chiquete
authors.affiliation: Department of Neurology, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Mexico.
authors.forename: José L
authors.initials: JL
authors.lastname: Ruiz-Sandoval
authors.affiliation: Department of Neurology, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Mexico.
authors.forename: Ana
authors.initials: A
authors.lastname: Ochoa-Guzmán
authors.affiliation: Department of Molecular Biology and Genomics, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Mexico.
authors.forename: Laura V
authors.initials: LV
authors.lastname: Sánchez-Orozco
authors.affiliation: Department of Nutrition, Universidad de la Sierra Sur de Oaxaca, Mexico.
authors.forename: Erika B
authors.initials: EB
authors.lastname: Lara-Zaragoza
authors.affiliation: Private Practice, Magdalena de Quino, Sonora, Mexico.
authors.forename: Nancy
authors.initials: N
authors.lastname: Basaldúa
authors.affiliation: Department of Chronic Degenerative Diseases, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Mexico.
authors.forename: Bertha
authors.initials: B
authors.lastname: Ruiz-Madrigal
authors.affiliation: Department of Molecular Biology and Genomics, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Mexico; Department of Molecular Biology, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Mexico.
authors.forename: Erika
authors.initials: E
authors.lastname: Martínez-López
authors.affiliation: Department of Molecular Biology and Genomics, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Mexico; Department of Molecular Biology, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Mexico.
authors.forename: Sonia
authors.initials: S
authors.lastname: Román
authors.affiliation: Division of Internal Medicine, Chairman; and Department of Endocrinology, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Guadalajara, Mexico.
authors.forename: Sergio A
authors.initials: SA
authors.lastname: Godínez-Gutiérrez
authors.affiliation: Department of Molecular Biology and Genomics, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Mexico; Department of Molecular Biology, Hospital Civil de Guadalajara "Fray Antonio Alcalde", Mexico.
authors.forename: Arturo
authors.initials: A
authors.lastname: Panduro
mesh_terms: D050154:Adiposity; D000328:Adult; D001823:Body Composition; D001827:Body Height; D015992:Body Mass Index; D002648:Child; D003430:Cross-Sectional Studies; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D009765:Obesity / Q000175:diagnosis / Q000453:epidemiology; D050177:Overweight / Q000175:diagnosis* / Q000453:epidemiology; D011795:Surveys and Questionnaires; D013851:Thinness; D055105:Waist Circumference; D049629:Waist-Hip Ratio
keywords: BMI; Body composition; Body fat; Composición corporal; IMC; Mexico; México; Obesity; Overweight; grasa corporal; obesidad; sobrepeso