Adiponectin levels during low- and high-fat eucaloric diets in lean and obese women

Objective: Adiponectin influences insulin sensitivity (S-I) and fat oxidation. Little is known about changes in adiponectin with changes in the fat content of eucaloric diets. We hypothesized that dietary fat content may influence adiponectin according to an individual's S-I. Research Methods and Procedures: We measured changes in adiponectin, insulin, glucose, and leptin in response to high-fat (HF) and low-fat (LF) eucaloric diets in lean (n = 10) and obese (n = 11) subjects. Obese subjects were further subdivided in relation to a priori S-I. Results: We found significantly higher insulin, glucose, and leptin and lower adiponectin in obese vs. lean subjects during both HF and LF. The mean group values of these measurements, including adiponectin (lean, HF 21.9 +/- 9.8; LF, 20.8 +/- 6.6; obese, HF 10.0 +/- 3.3; LF, 9.5 +/- 2.3 ng/mL. mean +/- SD), did not significantly change between HF and LF diets. However, within the obese group, the insulin-sensitive subjects had significantly higher adiponectin during HF than did the insulin-resistant subjects. Additionally,, the change in adiponectin from LF to HF diet correlated positively with the obese subjects' baseline S-I. Discussion: Although in lean and obese women, group mean values for adiponectin did not change significantly with a change in fat content of a eucaloric diet, a priori measured S-I in obese subjects predicted an increase in adiponectin during the HF diet; this may be a mechanism that preserves S-I in an already obese group.