Following along in my series of articles on lowering cholesterol (see the previous article The Importance of Targeting Saturated Fat), here we take a look at several studies that focused on saturated fats. By limiting the amount of these fats you consume, can you lower your cholesterol levels?
The guidelines suggest that you should lower saturated fats to less than seven percent of total energy intake for the day. There are three studies that show that this would lower LDL (bad) cholesterol by nine percent to 12% in a typical American diet.
One randomized controlled study consisted of 436 individuals. with a mean age of 44.6 years and total cholesterol of over 260 milligrams/deciliter (mg/dL), who consumed one of three diets: a control diet; a diet with an increased amount of fruit and vegetables; or the “DASH” diet, high in fruit, vegetables, and low-fat dairy products with reduced saturated fat, total fat, and cholesterol. The participants in this study on the DASH diet showed a nine-percent decrease in LDL cholesterol, 7.3% decrease in total cholesterol, 7.5% decrease in HDL (good) cholesterol, no change in triglycerides, and a greater reduction in LDL cholesterol and HDL cholesterol in those with higher levels at the start.
In another study, 36 individuals with high cholesterol were enrolled in the Therapeutic Lifestyle Change (TLC) Diet (seven percent saturated fatty acids, 66 mg/1,000 kcal cholesterol, 28% total fat) or a typical American diet (15% saturated fatty acid, 164 mg/1,000 kcal cholesterol, 39% total) for 32 days. The people on the TLC diet had an average 11% reduction in LDL cholesterol, seven-percent reduction in HDL cholesterol, and no change in triglycerides.
In the third study, 46 adults with high cholesterol were randomly assigned to undergo one of three interventions for one month: 1) A diet very low in saturated fat based on milled whole-wheat cereals and low-day diary food (control group); 2) The same diet, plus 20 mg of lovastatin a day; or 3) A diet high in plant sterols, soy protein, soluble fiber, and almonds (“dietary portfolio group”). It found that LDL cholesterol dropped by eight in the control group, 30.9% in the diet plus drug group, and 28.6% in the dietary portfolio group. To test whether the above findings were applicable to a real world setting, researchers examined 224 published studies involving 8,143 subjects and reported that the cholesterol-lowering effect of the ATP III TLC diet was in fact lower — between 4.5% and 7.7%.