The effects of peanut oil on lipid profile of normolipidemic adults: a three-country collaborative study

Abstract

Peanut oil has been associated with reduced levels of plasma cholesterol and triacylglycerol, possibly due to its high monounsaturated (MUFA) lipid profile. This study evaluated the effects of peanut oil intake on blood lipid levels of healthy, normolipidemic, young adults (18-50 y/o). One hundred twenty nine subjects were recruited in Brazil (32), Ghana (64), and in the United States (33). Men (64) and women (65) were assigned to 1 of 4 experimental groups: control (32), peanut (32), safflower (33), and olive oil (32). Participants received a daily milk shake containing 30% of their basal energy requirement as 1 of the test oils for 8 weeks, except the control group, which did not receive the shake. The levels of total cholesterol, HDL- cholesterol, LDL-cholesterol, and tria- cylglycerol were assayed at baseline and on weeks 4 and 8. Waist/hip ratio, blood pressure, and heart rate were also evalu- ated. The concentration of LDL-choles- terol was significantly reduced in the safflower group (p<0.05). Systolic and diastolic blood pressures were consis- tently lower in the olive oil group and for the Ghanaian participants in the peanut oil group (p<0.05). In conclusion, safflower oil elicited a stronger LDL- lowering property than peanut and olive oil, while olive oil, and to a lesser extent peanut oil, were more effective at reduc- ing blood pressure. The weak and inter- mediate effects of the peanut oil on cholesterol and blood pressure relative to the other oils suggest a contribution of its MUFA composition as well as other constituents in whole peanuts.