Youth and Long-Term Dietary Calcium Intake With Risk of Impaired Glucose Metabolism and Type 2 Diabetes in Adulthood

Context To the best of our knowledge, no previous studies have examined the role of youth calcium intake in the development of impaired glucose metabolism, especially those with long-term high calcium intake. Objectives To examine whether youth and long-term (between youth and adulthood) dietary calcium intake is associated with adult impaired glucose metabolism and type 2 diabetes (T2D). Design, setting, and participants The Cardiovascular Risk in Young Finns Study is a 31-year prospective cohort study (n = 1134; age, 3 to 18 years at baseline). Exposures Dietary calcium intake was assessed at baseline (1980) and adult follow-up visits (2001, 2007, and 2011). Long-term (mean between youth and adulthood) dietary calcium intake was calculated. Main outcome measures Adult impaired fasting glucose (IFG) and T2D. Results We found no evidence for nonlinear associations between calcium intake and IFG or T2D among females and males (all P for nonlinearity > 0.05). Higher youth and long-term dietary calcium intake was not associated with the risk of IFG or T2D among females or males after adjustment for confounders, including youth and adult body mass index. Conclusions Youth or long-term dietary calcium intake is not associated with adult risk of developing impaired glucose metabolism or T2D.