Meal fatty acid uptake in visceral fat in women

OBJECTIVE - Differential meal fat uptake into adipose tissue depots may be a determinant of body fat distribution. RESEARCH DESIGN AND METHODS - We used the meal fat tracer/adipose tissue biopsy approach to compare the effects of meal fat content on the fat uptake into visceral and upper and lower body subcutaneous fat depots in 21 premenopausal women. [³H]triolein was used to trace the fate of fatty acids from a normal-fat or high-fat meal. RESULTS - The proportion of dietary fat uptake into the three depots did not differ between meals; visceral fat accounted for only ∼5% of meal fat disposal irrespective of visceral fat mass. For the women consuming the normal-fat meal, the uptake of meal fatty acid into femoral fat (milligrams meal fat per gram lipid) increased as a function of leg fat mass (r = 0.68, P < 0.05), which we interpret as increased efficiency of uptake. The opposite pattern was seen in omental fat with the normal-fat meal and in all depots after the high-fat meal. For both meals, ∼40% of meal fat was oxidized ( ³H₂O production) after 24 h. CONCLUSIONS - We conclude that greater thigh adipose tissue in women is associated with greater efficiency of meal fat storage under conditions of energy balance, whereas the opposite is seen with visceral fat. These findings imply that different mechanisms may regulate fatty acid uptake in different depots, which may in turn impact on body fat distribution.