Weight Loss before Puberty Minimises Increased Risk of Developing Type 2 Diabetes as Adults in Boys who were Overweight
Childhood overweight at 7 years is associated with increased risks of type 2 diabetes in adulthood only if it continues until puberty or later ages, according to a study titled “Change in Overweight from Childhood to Early Adulthood and Risk of Type 2 Diabetes” published in the New England Journal of Medicine.
Being overweight in childhood and early adulthood is associated with an increased risk of developing type 2 diabetes in adult life. To determine whether or not weight loss in boys who were overweight or obese before early adulthood can reduce the risks of type 2 diabetes later in life, the researchers studied the associations between overweight patterns defined as combinations of weight status in childhood, adolescence and early adulthood, and later development of type 2 diabetes.
The researchers analysed data on 62,565 men in Denmark who were in the Copenhagen School Health Records Register and the Danish Conscription Database and who had weight and height measured at the ages 7 and 13 years, and in early adulthood (17-26 years). Overweight was defined by the U.S. Centers for Disease Control and Prevention criteria. The men were born between 1939 and 1959 and were followed in the Danish National Patient Register for information on type 2 diabetes. The study was supported by funding from the European Commission Horizon 2020 programme as part of the DynaHEALTH project, and by the European Research Council.
The study showed that being overweight in childhood, adolescence or in early adulthood was associated with up to 3.5 times higher risk of type 2 diabetes at ages 30-60 years. A total of 6,710 of the men were diagnosed with type 2 diabetes at 30 years of age or older. Men who had been overweight at 7 years of age but normalised weight by age 13 years and were normal weight as young men had similar risks of type 2 diabetes, diagnosed at 30 to 60 years of age, as men who were never overweight. Men who normalised weight between age 13 and early adulthood had increased risks of type 2 diabetes, but lower risks than men who were overweight at all ages, indicating that the adverse effects of overweight at 13 years are partly reversible. Men who became overweight at 13 years or were persistently overweight had four times the risk of developing type 2 diabetes at ages 30-60 years, as compared with men who were never overweight.
“These findings suggest that the adverse effects of overweight at 7 years of age on type 2 diabetes risk may possibly be reversed by losing weight before puberty and maintaining normal weight until early adulthood. In comparison, the adverse effects of overweight at 13 years are only partly reversible,” said the study’s lead author Lise G. Bjerregaard, PhD, postdoctoral research fellow, Center for Clinical Research and Disease Prevention, Bispebjerg and Frederiksberg Hospital in Copenhagen, Denmark. The study’s senior author, Associate Professor Jennifer L. Baker, from the Center for Clinical Research and Disease Prevention and the Novo Nordisk Foundation Center for Metabolism and Basic Research, Section for Metabolic Genetics, at the University of Copenhagen, said “These results show the importance of preventing and treating overweight in children, especially before puberty, as it may greatly reduce their risk of type 2 diabetes later in life”.
The article in the New England Journal of Medicine (2018) is "Change in Overweight from Childhood to Early Adulthood and Risk of Type 2 Diabetes," by Lise G. Bjerregard et al. DOI: 10.1056/NEJMoa1713231.