Effectiveness of a low-fat vegetarian diet in altering serum lipids in healthy premenopausal women

Few controlled trials have studied cholesterol-lowering diets in premenopau sal women. None has examined the cholesterol-lowering effect of a low-fat v egetarian diet, which, in other population groups, leads to marked reductio ns in serum cholesterol concentrations and, in combination with other life- style changes, a regression of atherosclerosis. We tested the hypothesis th at a low-fat, vegetarian diet significantly reduces serum total and low-den sity lipoprotein (LDL) cholesterol concentrations in premenopausal women. I n a crossover design, 35 women, aged 22 to 48, followed a low-fat vegetaria n diet deriving approximately 10% of energy from fat for 2 menstrual cycles . For 2 additional cycles, they followed their customary diet while also ta king a "supplement" (placebo) pill. Serum lipid concentrations were assesse d at baseline and during each intervention phase. Mean serum LDL, high-dens ity lipoprotein (HDL), and total cholesterol concentrations decreased 16.9% , 16.5%, and 13.2%, respectively, from baseline to the intervention diet ph ase (p <0.001), whereas mean serum triacylglycerol concentration increased 18.7% (p <0.01). LDL/HDL ratio remained unchanged. Thus, in healthy premeno pausal women, a low-fat vegetarian diet led to rapid and sizable reductions in serum total, LDL, and HDL cholesterol concentrations. (C) 2000 by Excer pta Medica, Inc.