AN NCEP-II DIET REDUCES POSTPRANDIAL TRIACYLGLYCEROL IN NORMOCHOLESTEROLEMIC ADULTS

We compared the fasting and postprandial response to a National Choles terol Education Program (NCEP) II diet with that of a diet high in tot al (40% of energy) and saturated fat. In free-living conditions, 17 he althy normolipidemic, normoglycemic men and women consumed a high-fat diet, a maintenance diet and the NCEP II diet, for 1 mo each. At the c ompletion of each dietary period, an oral fat load (70 g/m(2) body sur face area) was administered and plasma triacylglycerol (TAG) determine d every 2 h for 8 h. Compared with the high-fat phase, the NCEP II die t was associated with significantly lower energy intake (12.1 +/- 1.1 vs, 7 +/- 0.7 MJ/d) and final body weight (78 +/- 3.8 vs. 76.3 +/- 3.5 kg) (P < 0.01). Plasma high density lipoprotein cholesterol, apolipop rotein (ape) A-I and ApoB concentrations were also significantly lower when subjects consumed the NCEP II diet rather than the high-fat diet (P less than or equal to 0.004). There were no significant difference s in subjects fasting TAG, glucose or insulin concentration between th e high fat and NCEP II diet periods. However, the postprandial plasma TAG response to the fat load was lower after completing the NCEP II th an after the high-fat diet period (P = 0.045), Under free-living condi tions, a NCEP II diet was associated with weight loss and a decrease i n postprandial but not fasting TAG. Because dietary alteration may not affect fasting TAG levels, thorough assessment of a dietary intervent ion should include measurements of postprandial TAG.