Background: Low-fat diets increase plasma triacylglycerol and decrease HDL-cholesterol concentrations, thereby potentially adversely affecting cardiovascular disease (CVD) risk. High-monounsaturated fatty acid (MUFA), cholesterol-lowering diets do not raise triacylglycerol or lower HDL cholesterol, but little is known about how peanut products, a rich source of MUFAs, affect CVD risk.Objective: The present study compared the CVD risk profile of an Average American diet (AAD) with those of 4 cholesterol-lowering diets: an American Heart Association/National Cholesterol Education ProgramStep II diet and 3 high-MUFA diets [olive oil (OO), peanut oil (PO), and peanuts and peanut butter (PPB)]. Design: A randomized, double-blind, 5-period crossover study design (n = 22) was used to examine the effects of the diets on serum lipids and lipoproteins: AAD [34% fat; 16% saturated fatty acids (SFAs), 11% MUFAs], Step II (25% fat; 7% SFAs, 12% MUFAs), OO (34% fat; 7% SFAs, 21% MUFAs), PO (34% fat; 7% SFAs, 17% MUFAs), and PPB (36% fat; 8% SFAs, 18% MUFAs).
Results:The high-MUFA diets lowered total cholesterol by 10% and LDL cholesterol by 14%. This response was comparable with that observed for the Step II diet. Triacylglycerol concentrations were 13% lower in subjects consuming the high-MUFA diets and were 11% higher with the Step II diet than with the AAD. The high-MUFA diets did not lower HDL cholesterol whereas the Step II diet lowered it by 4% compared with the AAD. The OO, PO, and PPB diets decreased CVD risk by an estimated 25%, 16%, and 21%, respectively, whereas the Step II diet lowered CVD risk by 12%. Conclusion: A high-MUFA, cholesterol-lowering diet may be preferable to a low-fat diet because of more favorable effects on the CVD risk profile.Am J Clin Nutr 1999;70:1009-15.
KEY WORDSPlasma triacylglycerol, HDL cholesterol, LDL cholesterol, monounsaturated fatty acids, dietary fat, peanuts, peanut products, Step II diet, cardiovascular disease, humans
INTRODUCTIONDiet is the cornerstone of the prevention and treatment of cardiovascular disease (CVD). Currently, National Cholesterol Education Program/American Heart Association Step I or Step II diets are typically recommended for lowering blood cholesterol concentrations. The primary objective of these diets is to lower saturated fat (8-10% and < 7% of energy, respectively), cholesterol (300 or 200 mg/d), and total fat (< 30% of energy). Typically, a Step I diet lowers total cholesterol and LDL cholesterol by Ϸ5-7% (1-3). A Step II diet can lower total cholesterol and LDL cholesterol an additional 3-7% (1, 2). In these diets, saturated fat energy is replaced by carbohydrate, resulting in a low-fat, high-carbohydrate diet. Although these diets have beneficial effects on total cholesterol and LDL cholesterol, they increase plasma triacylglycerol concentrations and decrease HDL-cholesterol concentrations, thereby potentially adversely affecting CVD risk. This has caused some to question whether a Step I or Step II diet is the ideal diet for maximally reducing...