Thigh Adipocyte Size is Inversely Related to Energy Intake and Respiratory Quotient in Healthy Women

OBJECTIVE The relationship between adipocyte size and ad libitum energy intake has not been previously examined. This study hypothesized an inverse relationship between adipocyte size and daily energy intake (DEI). METHODS Seventy healthy adults (39 men and 31 women; BMI 30.0 [SD 6.3]) underwent dual-energy x-ray absorptiometry and subcutaneous fat biopsies from the abdomen and thigh. Osmium-fixed adipocytes were sized with a Coulter counter. Volunteers self-selected food from a vending machine paradigm as the only source of energy intake over 3 days as inpatients. Volunteers also had 24-hour respiratory quotient (RQ) measured in a whole-room indirect calorimeter. RESULTS In women, the large cell peak diameter of the thigh depot was greater than that of the abdominal depot (Δ = +15.8 μm; P