title: A changing pattern of childhood BMI growth during the 20th century: 70 y of data from the Fels Longitudinal Study.
abstract: BACKGROUND
  The BMI distribution shifted upward in the United States between the 1960s and the 1990s, but little is known about secular trends in the pattern of BMI growth, particularly earlier in the century and early in childhood.
  
  
  OBJECTIVE
  The objective was to examine differences in BMI growth in children born in 1929-1999.
  
  
  METHODS
  BMI curves from ages 2 to 18 y were produced for 855 European-American children in the Fels Longitudinal Study born in 1929-1953, 1954-1972, and 1973-1999. Age (A(min)) and BMI (BMI(min)) at adiposity rebound and age (AV(max)), BMI (BMIV(max)), and velocity (V(max)) at maximum velocity were derived; multivariable regression was used to examine whether maternal BMI, infant weight gain, and other covariates mediated the cohort effects on these traits.
  
  
  RESULTS
  BMI curves showed that children born in 1973-1999 had the lowest BMI values until age 5 y but had the largest values from age 8 y onward. In adjusted models, boys and girls born in 1973-1999 had a 0.15-kg/m(2) per year faster V(max) and a 1-kg/m(2) higher BMIV(max) than did children of the same sex born in 1929-1953, and girls had a 0.8-y earlier A(min) (P < 0.01). Maternal BMI and infant weight gain were associated with an obesity-prone pattern of BMI growth but did not account for the observed trends.
  
  
  CONCLUSIONS
  Shifts in the BMI growth rate around the time of pubertal initiation were apparent starting after 1973. The BMI growth curve did not increase monotonically over time; rather, children born during the obesity epidemic were characterized by lower BMI values before the adiposity rebound and by rapid subsequent BMI gain.
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN 55454, USA.
authors.forename: William
authors.initials: W
authors.lastname: Johnson
authors.forename: Laura E
authors.initials: LE
authors.lastname: Soloway
authors.forename: Darin
authors.initials: D
authors.lastname: Erickson
authors.forename: Audrey C
authors.initials: AC
authors.lastname: Choh
authors.forename: Miryoung
authors.initials: M
authors.lastname: Lee
authors.forename: William C
authors.initials: WC
authors.lastname: Chumlea
authors.forename: Roger M
authors.initials: RM
authors.lastname: Siervogel
authors.forename: Stefan A
authors.initials: SA
authors.lastname: Czerwinski
authors.forename: Bradford
authors.initials: B
authors.lastname: Towne
authors.forename: Ellen W
authors.initials: EW
authors.lastname: Demerath
mesh_terms: D050154:Adiposity; D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D005260:Female; D057238:Growth Charts; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D009765:Obesity / Q000453:epidemiology* / Q000208:ethnology; D014481:United States / Q000453:epidemiology; D015430:Weight Gain; D044465:White People