The development of young adult obesity and its role on diabetes

Given the numerous medical and economic consequences of obesity, a better understanding of its etiology is needed for effective prevention. Notably, there has been relatively little research documenting the natural progression of obesity using a life course approach. It is unknown whether obesity is a result of exposures during sensitive periods of the life course that act independently and/or cumulatively to influence adult health. In fact, much of the knowledge regarding determinants of obesity has emerged from studies that examine how factors relate to disease risk during the same period. Given evidence that the prevention of obesity can reduce the burden of chronic conditions, research using a life course approach is warranted. Our research utilizes a life course approach to understand the development of obesity and diabetes. Specifically, we examine the associations between (1) birthweight and obesity in adolescence and adulthood, (2) adolescent obesity and risk of severe obesity in adulthood, and (3) the effect of obesity timing and duration on diabetes in adulthood. These analyses were conducted using the National Longitudinal Study of Adolescent Health, a nationally representative cohort of over 20,000 adolescents followed over 14 years into young adulthood. To disentangle genetic versus environmental factors underlying the relationship between birthweight and obesity, we used a traditional cohort and a subsample of matched full-sibling and twins. We observed that birthweight is an important determinant of adolescent/adulthood obesity with interesting nuances by sex and sibling type. Our findings suggest that obese adolescents are at higher risk for becoming severely obese in adulthood than normal weight adolescents, with highest risk in black females. Lastly, we demonstrate important consequences of adolescent obesity and persistence of obesity on diabetes risk. In summary, this research makes significant contributions to the field by using a life course approach. Further, our research underscores the need to prevent the development of obesity prior to adolescence