Maternal obesity is associated with younger age at obesity onset in U.S. adolescent offspring followed into adulthood.

Objective: The objective was to test the hypothesis that maternal obesity is associated with younger age of offspring's obesity onset.

Research Methods And Procedures: We used prospective, nationally representative, longitudinal data collected across Waves I (1995; 12 to 20 years), II (1996; 13 to 20 years), and III (2001; 18 to 28 years) of the National Longitudinal Study of Adolescent Health (N = 14,654; 49% female). Interval regression analysis was used to assess the association between maternal obesity and age at offspring's obesity onset (International Obesity Task Force BMI >or=30 equivalent age- and sex-specific cut-off points for adolescents and BMI >or=30 for young adults) using self-reported heights and weights, adjusting for race/ethnicity, sex, parental education, and family income, accounting for complex sampling design.

Results: The net effect of having an obese mother varied by race/ethnicity and was associated with a significantly earlier age at obesity onset (p = 0.0001) for whites [beta= -8.1 year, 95% confidence interval (CI), -9.3; -6.9)], blacks (beta = -10.8 years, 95% CI, -12.4; -9.2), Hispanics (beta = -7.0 years, 95% CI, -9.2; -4.8), and Asians (beta = -8.6 years, 95% CI, -13.3; -3.9). Earlier obesity onset (<18 years) was associated with increased severity at young adulthood (mean BMI, 36.0 +/- 0.3 kg/m(2)) vs. onset after age 18 (mean BMI, 34.4 +/- 0.2 kg/m(2); p = 0.0001). There were no sex differences in the association of maternal obesity to age at obesity onset.

Conclusions: Having an obese mother was associated with earlier age at obesity onset across all race/ethnic groups, particularly non-Hispanic blacks. Early obesity onset has important health consequences because of its association with more severe adult obesity.