Stearic acid, trans fatty acids, and dairy fat: effects on serum and lipoprotein lipids, apolipoproteins, lipoprotein(a), and lipid transfer proteins in healthy subjects

Abstract

To compare the effects on serum lipoproteins of stearic acid, trans fatty acids, and dairy fat, 80 healthy subjects consumed a dairy fat-based (baseline) diet for 5 wk, then an experimental diet high in either trans fatty acids (8.7% of energy; n = 40) or stearic acid (9.3% of energy; n = 40) for another 5 wk. All diets provided 32.2-33.9% of energy as fat, 14.6-15.8% as saturated plus trans fatty acids, 11.4-12.5% as cis-monounsaturated fatty acids, 2.9-3.5% as polyunsaturated fatty acids, and 200-221 mg cholesterol/10 MJ. Compared with the dairy fat diet, stearic acid and trans fatty acids decreased serum total cholesterol concentrations similarly (by 13% and 12%, respectively, P < 0.001) but the trans fatty acid diet decreased HDL cholesterol (17%) and apolipoprotein (apo) A-I (15%) significantly more than did the stearic acid diet (11% and 12%, respectively). Stearic acid but not trans fatty acids reduced concentrations of LDL cholesterol and apo B significantly (P < 0.001). The trans fatty acid diet increased the ratio of LDL to HDL cholesterol (19%) and of apo B to apo A-I (16%) more than did the dairy fat diet (P < 0.001) but the stearic acid diet had no effect. Lipoprotein(a) concentrations increased with both experimental diets, significantly more with trans fatty acids (30%) than with stearic acid (10%). In conclusion, high amounts of trans fatty acids had more adverse effects on lipoproteins than did equal amounts of stearic acid and dairy fat. Stearic acid reduced LDL cholesterol, did not affect the ratio of LDL to HDL cholesterol, and increased lipoprotein(a), although to a lesser extent than did trans fatty acids. Dietary fats low in both saturated fatty acids and trans fatty acids should be favored.

Trans fats—sources, health risks and alternative approach - A review

“…TFA consumption also increased serum triglyceride and lipoprotein levels and reduced LDL particle size in controlled trials indicating higher risk of coronary heart disease. These adverse effects of trans fatty acids have been confirmed by subsequent metabolic studies (Aro et al 1997;Judd et al 1994;Lichtenstein et al 1999;Zock et al 1995). Williams et al (1998) established an association between TFA and incidence of non-fatal myocardial infarction from coronary heart disease.…”

The occurrence of trans-18:1 isomers in plasma lipids classes in humans

“…Lipoprotein(a) (Lp(a)), an independent risk factor for cardiovascular disease (CVD), was also signi®cantly higher in diets enriched with TFA compared with oleic acid or a saturated fatty acids (SFA) diet (Nestel et al, 1992;Katan et al, 1995;Aro et al, 1995).…”

Analysis of co-crystallized free phytosterols with triacylglycerols as a functional food ingredient

“…When compared with the dairy fat diet, similarly both stearic and trans fatty acids decreased total serum cholesterol concentrations by 13% and 12% (Aro et al, 1997). However, the trans fatty acid diet decreased HDL cholesterol by 17% while stearic acid only decreased HDL cholesterol by 11% (Aro et al, 1997).…”

“…However, the trans fatty acid diet decreased HDL cholesterol by 17% while stearic acid only decreased HDL cholesterol by 11% (Aro et al, 1997). In regards to lowering harmful LDL cholesterol, only the stearic acid diet decreased LDL concentrations significantly (Aro et al, 1997). In fact, the trans fatty acid diet increased the harmful LDL to HDL ratio by 19% as compared to the dairy fat baseline diet (Aro et al, 1997).…”

“…In a study comparing effects on serum lipoproteins between stearic acid and trans fatty acid, 80 healthy subjects consumed a dairy fat-based diet as a baseline, then an experimental diet high in either stearic acid (Aro, Jauhiainen, Partanen, Salminen, & Mutanen, 1997). When compared with the dairy fat diet, similarly both stearic and trans fatty acids decreased total serum cholesterol concentrations by 13% and 12% (Aro et al, 1997).…”