Effects of an American Heart Association diet and weight loss on lipoprotein lipids in obese, postmenopausal women.

The sequential effects of an American Heart Association (AHA) Step 1 diet and subsequent weight loss on lipoprotein lipids in obese [body mass index (in kg/m2) > 27], postmenopausal women (n = 48) were determined. Subjects followed a euenergetic AHA Step 1 diet for 2 mo, followed by a weight-loss diet (deficit of 1.0-1.5 MJ/d) for 6 mo. The AHA diet lowered concentrations of total (7%), low-density-lipoprotein (LDL) (6%), and high-density-lipoprotein (HDL) (14%) cholesterol (P < 0.01). Weight loss (-5.6 +/- 0.7 kg; P < 0.01) increased plasma triacylglycerol concentrations (9%; P < 0.01) and increased HDL-cholesterol concentrations (8%; P < 0.01) compared with changes after the AHA diet, but there were no changes in total or LDL cholesterol. The combined AHA diet and weight-loss interventions lowered triacylglycerol (10%) and total (6%), LDL (6%), and HDL (7%) cholesterol. These changes correlated indirectly with the baseline concentration for each lipid. When the women were divided on the basis of initial LDL-cholesterol concentration, the AHA diet and weight-loss interventions reduced (P < 0.01) triacylglycerol (19%), total cholesterol (13%), and LDL cholesterol (14%) in the women with hypercholesterolemia but not in normocholesterolemic or midly hypercholesterolemic women. Thus, an AHA Step 1 diet and subsequent weight loss improve lipoprotein lipid profiles of obese, postmenopausal women with hypercholesterolemia. However, because it lowers HDL cholesterol, a low-fat diet without substantial weight loss may not be beneficial for improving lipoprotein lipid risk factors for coronary artery disease in obese, postmenopausal women with normal lipid profiles.