Objective: To study the relationship between BMI at age 18 years and later attained education, with control for intelligence and parental social position.
Research Methods and Procedures: A cohort of 752,283 Swedish men born from 1952 to 1973 were followed in registers with respect to attainment of high education (≥15 years of education) until December 31, 2001. Intelligence and BMI (kilograms per meter squared) were measured at compulsory military conscription at age 18 years. Ninth grade school marks were available for a subgroup born from 1972 to 1973 (N = 93,374). The hazard ratio for attaining high education was estimated with proportional hazard regression analysis controlling for intelligence, height, parental socioeconomic position, country of birth, conscription center, and municipality.
Results: Young men who were obese (BMI ≥ 30) at age 18 years (N = 10,782) had a much lower chance of attaining a high education than normal-weight subjects [(18.5 ≤ BMI < 25); adjusted hazard ratio 0.48 (95% confidence interval, 0.45, 0.52)]. Young men who were obese at age 18 had lower mean ninth grade school marks than young men with normal weight at any given intelligence level.
Discussion: Obese men in Sweden are doing much worse in the educational system than their normal-weight counterparts even after adjustments for intelligence and parental socioeconomic position. Discrimination in the educational system and other sectors of the society may explain these strong associations.