Journal: The American Journal of Clinical Nutrition
Publication Date: 09/2015
Summary: Heart associations recommend limited intake of saturated fat. However, effects of saturated fat on low-density lipoprotein (LDL)-cholesterol concentrations and cardiovascular disease risk might depend on nutrients and specific saturated fatty acids (SFAs) in food. We explored the effects of cheese and meat as sources of SFAs or isocaloric replacement with carbohydrates on blood lipids, lipoproteins, and fecal excretion of fat and bile acids. The study was a randomized, crossover, open-label intervention in 14 overweight postmenopausal women. Three full diet periods of 2-wk duration were provided separated by 2-wk washout periods. The isocaloric diets were as follows: 1) a high- cheese (96–120-g) intervention [i.e., intervention containing cheese (CHEESE)], 2) a macronutrient-matched nondairy, high-meat control [i.e., nondairy control with a high content of high-fat processed and unprocessed meat in amounts matching the saturated fat content from cheese in the intervention containing cheese (MEAT)], and 3) a nondairy, low-fat, high-carbohydrate control (i.e., nondairy low-fat control in which the energy from cheese fat and protein was isocalorically replaced by carbohydrates and lean meat (CARB). The CHEESE diet caused a 5% higher high-density lipoprotein (HDL)-cholesterol concentration (P = 0.012), an 8% higher apo A-I concentration (P , 0.001), and a 5% lower apoB:apo A-I ratio (P = 0.008) than did the CARB diet. Also, the MEAT diet caused an 8% higher HDL-cholesterol concentration (P , 0.001) and a 4% higher apo A-I concentration (P = 0.033) than did the CARB diet. Total cholesterol, LDL cholesterol, apoB, and triacylglycerol were similar with the 3 diets. Fecal fat excretion was 1.8 and 0.9 g higher with the CHEESE diet than with CARB and MEAT diets (P , 0.001 and P = 0.004, respectively) and 0.9 g higher with the MEAT diet than with the CARB diet (P = 0.005). CHEESE and MEAT diets caused higher fecal bile acid excretion than did the CARB diet (P , 0.05 and P = 0.006, respectively). The dominant type of bile acids excreted differed between CHEESE and MEAT diets.
Diets with cheese and meat as primary sources of SFAs cause higher HDL cholesterol and apo A-I and, therefore, appear to be less atherogenic than is a low-fat, high-carbohydrate diet. Also, our findings confirm that cheese increases fecal fat excretion.