The effect of fat on lipid profiles in the abdominally obese postmenopausal woman

Thirty-three postmenopausal women with abdominal obesity participated in a weight reduction study. The purpose was to determine if a low-fat, reduced kcalorie diet would improve the lipid profile in abdominally obese postmenopausal women when compared to a reduced kcalorie normal-fat diet. Subjects were randomly assigned to either a control group or to one of two weight reduction (1200 kilocalorie) diets: one having a normal fat level and the other being low in fat, for six weeks. The low calorie, normal-fat diet contained 2 0% protein, 30-35% fat and 40-50% carbohydrate, whereas the low-fat diet contained 20% protein, 20-25% fat and 55-60% carbohydrate. Fasting serum total cholesterol, HDLcholesterol and triglyceride were measured initially and at the end of 6 weeks. Weight loss regimens improved two parameters significantly (p < 0.001), by decreasing waistto-hip ratio (WHR) and body mass index (BMI) (p < 0.001) in a ll experimental subjects. Total serum cholesterol decreased significantly (p < 0.004) in the group consumlng the low-fat diet. However, cholesterol levels in the control group and the group consuming the normal-fat diet did not change significantly. Triglyceride levels and HDL-cholesterol levels did not change significantly ln any of the diet groups. Due to an increased caloric intake by the lowcalorie, normal-fat diet group, data were reorganized into a post-hoc control diet group and a reduced-fat diet group. Statistical analysis of the reorganized data confirmed that significant (p < 0.01) decreases in body weight and BMI occurred ln the reduced-fat diet group. A significant decrease (p < 0.01) in WHR occurred in both the post-hoc control diet group and the reduced-fat diet group. However, the reduced-fat diet group was the only group to experience any significant (p < 0.01) decrease in blood lipid concentrations. These findings suggest that an energyrestricted, reduced-fat diet may be necessary to successfully decrease cholesterol concentrations ln abdominally obese postmenopausal women.