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Effect of butter, mono- and polyunsaturated fatty acid-enriched butter, trans fatty acid margarine, and zero trans fatty acid margarine on serum lipids and lipoproteins in healthy men
Randall Wood,’ Karen Kubena, Barbara O’Brien, Stephen Tseng, and Gail Martin
Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843-2128

Abstract The effect of dietscontaining 50% of fat calories from butter, butter enriched with mono- and polyunsaturated fatty acids, and margarines with and without trans fatty acids on the serum lipids of 38 healthy men in a free-living condition have been determined. Serum lipid responses to the high level of individual dietary fats were unexpectedly small. The butter diet produced a small, but significant rise (5%) in the totalserum cholesterol and low density lipoprotein (LDL)-cholesterol, relative to all other diets. Enrichment of butter with either olive oil (50/50) or sunflower oil (50/50) failed to reduce serum lipid levels below habitual diet values. Hard margarine, containing 29% trans fatty acids, caused a decrease in apolipoprotein A-I and B levels, but did not change total serum cholesterol or LDLcholesterollevels, relative to habitual diet values. A soft margarine, high in linoleate, with no trans fatty acids reduced total cholesterol, LDL-cholesterol, and apolipoprotein B significantly, relative to all diets. Soft margarine high density lipoprotein (HDL)-cholesterol levels remained unchanged, but apolipoprotein A-I values were decreased relative to habitual and butter diets. The quantities ofsaturated fatty acids and the sum of monounsaturated and polyunsaturated fatty acids consumed on the hard and soft margarines were equal; therefore, the different response of serum cholesterol and LDL-cholesterol between these two diets is attributable to the trans fatty acids in the hard The data indicate that trans fatty acids are not margarine. I metabolically equivalent to the natural cis isomers andthat they affect the serum lipid profile adversely.-Wood, R.,K. Kubena, B. O’Brien, S. Tseng, a n d G . Martin. Effect of butter, monoand polyunsaturated fatty acid-enriched butter, trans fatty acid margarine, and zero trans fatty acid margarine on serum lipids and lipoproteins of healthy men. J Lipid Res. 1993. 34: 1-11.
Supplementary key words dietary fat
cholesterol

B, E

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saturatedfatty acids dietary cholesterol triglycerides apolipoproteins A-I, HDL-cholesterol LDL-cholesterol trans fatty acids
serum

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or exacerbate atherogenesis (1). Classical studies by Ahrens et al. (2), Keys, Anderson, and Grande (3), and Hegsted et al. ( ) using hospitalized patients on liquid 4, formula diets or institutionalized schizophrenic patients on solid foods, have provided thebasis for the hypothesis. Over the years there have been, and continue to be, studies to examine the various components of “dietary fat” for their effect on serum lipids. Dietary cholesterol, first reported to have no effect on serum cholesterol (5), is now generally accepted to elevate serum cholesterol 4-5 mg/dl with each 100 mg increase in dietary cholesterol (6-8). Monounsaturated fatty acideffects were first considered as being neutral with regard to serum cholesterol (3), however the work of Grundy and colleagues (9-11) has shown that monounsaturated fatty acids are as effective as polyunsaturated fatty acids in lowering serum cholesterol. Initially, stearic acid, a saturated fatty acid, was considered to have no effect on serum cholesterol (12, 13), but it now has been reported tolower serum cholesterol (14). Myristic acid has been reported to be the strongest serum cholesterolelevating fatty acid (4) while others contend that palmitic is the culprit (15). The early classical studies (2-4) indicated diets containing high levels of polyunsaturated fatty acids were effective in lowering serum cholesterol levels, however studies in recent years have demonstrated that...