Childhood obesity tied to increased risk of type 1 diabetes, study suggests

UK: A recent study in the journal Nature Communications has found that childhood body size has a causal influence on the type 1 diabetes (T1D) risk. Its influence on other immune-associated diseases is likely due to the long-term effect of remaining overweight for many years over the life course.

"We present evidence indicating that body size in childhood increases the T1D risk based on the age-at-diagnosis of the participants analyzed in this study (mean age = 16.57 years)," the authors wrote in their study. "Our findings support results from previous observational studies suggesting that the increasing prevalence of childhood obesity is a causal factor in the rising numbers of T1D diagnoses. 

The increasing prevalence of childhood obesity has been postulated as the reason for the increasing rate of individuals diagnosed with type 1 diabetes. Tom G. Richardson, Novo Nordisk Research Centre Oxford, Old Road Campus, Oxford, United Kingdom, and colleagues used Mendelian randomization (MR) to provide evidence that childhood body size has an effect on T1D risk (OR = 2.05 per change in body size category), which remains after accounting for body size at birth and during adulthood using multivariable MR (OR = 2.32).

Using data from a large-scale T1D meta-analysis based on n = 15,573 cases and n = 158,408 controls (OR = 1.94), the researchers validate the direct effect of childhood body size. Also, they provided evidence that childhood body size influences the risk of eczema, asthma, and hypothyroidism. Although multivariable MR suggested that in later life these effects are mediated by body size. 

"Our findings emphasize the importance of implementing preventative policies to lower the prevalence of childhood obesity and its subsequent influence on the rising numbers of T1D cases," the authors write. "This will help ease health care burdens and also potentially improve the quality of life for individuals living with this lifelong disease." 

Reference:

Richardson, T.G., Crouch, D.J.M., Power, G.M. et al. Childhood body size directly increases type 1 diabetes risk based on a lifecourse Mendelian randomization approach. Nat Commun 13, 2337 (2022). https://doi.org/10.1038/s41467-022-29932-y