Plasma levels of glucagon-like peptide 1 and markers of obesity among young and healthy adults.

OBJECTIVE

Glucagon-like peptide 1 (GLP-1)-related pathways may partially explain the strong relationship between obesity and type 2 diabetes. We therefore aimed to evaluate the relationships between fasting GLP-1 levels, body fat mass and other obesity markers in a large sample of young and healthy adults.

DESIGN AND PATIENTS: Our population-based study included 2096 individuals aged 24-44. Exclusion criteria were prevalent cardiovascular disease, diabetes or a body mass index (BMI) >35 kg/m(2) . Body fat mass was obtained by bioelectrical impedance analysis. Multivariable linear regression models were constructed to assess the relationships of GLP-1 with various measures of body composition.

RESULTS

Median age of our population was 37 years, median BMI 24·1 kg/m(2) and median body fat 25·1%. A strong positive correlation was observed in age-adjusted models between GLP-1 and fat mass in men (β (95% confidence interval) 1·38 (0·69; 2·07), P < 0·001) and women (1·27 (0·65; 1·89), P < 0·001) as well as fully adjusted models including BMI in men [0·87 (0·27; 1·46), P < 0·01] but not women [0·29 (-0·07; 0·64), P = 0·11]. The relationships of GLP-1 with BMI for men and women [0·00 (-0·34; 0·34), P = 0·99] [-0·02 (-0·28; 0·25), P = 0·91] and waist circumference [0·43 (-0·45; 1·30), P = 0·34] [0·37 (-0·44; 1·18), P = 0·37], respectively, were not significant after multivariable adjustment including fat mass.

CONCLUSION

Among young and healthy adults, GLP-1 levels are strongly and independently related to body fat mass especially in men but not BMI or waist circumference. These results raise the hypothesis that GLP-1 may be implicated in body fat mass regulation.