Am J Clin Nutr 1994;59:861-8. Printed in USA. © 1994 American Society for Clinical Nutrition 861 Dietary trans fatty acids: effects on plasma lipids and lipoproteins of healthy men and women13

ABSTRACT Effects of cis and trans monounsatunated fatty acids (TFA) and saturated fatty acids were assessed in 29 men and 29 women consuming controlled diets. Subjects ate each diet for 6 wk in a Latin square design. The diets, each with 39-40% of energy as fat were: 1) high oleic (16.7 % of energy as oleic acid), 2) moderate TFA (3.8 % of energy as TFA), 3) high TFA (6.6 % of energy as TFA), 4) and saturated (16.2 % of energy as launic + mynistic + palmitic acids). Compared with the oleic diet, LDL cholesterol increased 6.0%, 7.8%, and 9.0 % after moderate TFA, high TFA, and saturated diets, respectively. HDL choles-terol was unchanged aften moderate TFA, but was slightly lower (2.8%) after high TFA. HDL cholesterol after the saturated diet was 3.5 % higher than after the oleic diet. Changes in apolipo-proteins B and A-I corresponded with changes in the lipoprotein cholestenols. Thus, compared with oleic acid, dietary TFAs raise LDL cholesterol, but to a slightly lessen degree than do saturates, and high TFA concentrations may result in minor reductions of HDL cholesterol. AmJ Clin Nutr 1994;59:861-8. KEY WORDS Dietary fat, dietary cis and trans fatty acids, blood lipids, lipoproteins, hydrogenated fats, controlled diet ef-fects in men and women, dietary saturated fatty acids, plasma cholestero