SCOPEAbdominal obesity is one of the main modifiable risk factors of age-related cardiometabolic disease. Cardiometabolic disease risk and its associated high abdominal fat mass, high cholesterol and glucose concentrations can be reduced by a healthier lifestyle. Hence, our aim is to understand the relation between lifestyle-induced changes in body composition, and specifically abdominal fat, and accompanying changes in circulating metabolic biomarkers.Methods and resultsWe used the data from the Growing Old Together (GOTO) study, in which 164 older adults (mean age 63 years, BMI 23-35 kg/m2) changed their lifestyle during 13 weeks by 12.5% caloric restriction plus 12.5% increase in energy expenditure. We show that levels of circulating metabolic biomarkers, even after adjustment for body mass index, specifically associate with abdominal fat mass. Next, we show that the applied lifestyle intervention mainly reduces abdominal fat mass (−2.6%, SD=3.0) and that this reduction, when adjusted for general weight loss, is highly associated with decreased circulating glycerol concentrations and increased HDL diameter.ConclusionsThe lifestyle-induced reduction of abdominal fat mass is particularly associated, independent of body mass index or general weight loss, with associated with decreased circulating glycerol concentrations and increased HDL diameter.