Abstract
PURPOSE: Excess body fat is a commonly known risk factor for type 2 diabetes. However, whether lean body mass, or fat free mass, could have a protective effect against type 2 diabetes, remains unclear. The aim of this study was to explore the association between lean body mass, fat mass and type 2 diabetes. METHODS: This study used data from the Danish Diet, Cancer and Health cohort of 37,053 men and women, aged 50-64 years at baseline (1993-1997). The exposure was measurements of body composition using bioelectrical impedance analysis. Incident diabetes during follow-up was determined through linkage to the Danish National Diabetes Register. Cox proportional hazards regression analysis was used to estimate HR and 95%CI for the association between lean body mass and incident type 2 diabetes, with and without adjustment for fat mass. A sensitivity analysis was performed, excluding cases of incident type 2 diabetes within the first 2 years of follow-up. RESULTS: When adjusted for fat mass, the main analysis showed non-linear inverse association between lean body mass and risk of diabetes for men, but not for women. However, the sensitivity analysis found no association for either men or women. CONCLUSIONS: Lean body mass was not associated with incident type 2 diabetes when excluding cases that may have been subclinical at baseline. The results imply that public health should focus on reduction of fat mass for diabetes prevention.