Effect of changing dietary fat saturation on low-density lipoprotein metabolism in man

Am J Physiol. 1981 Jul;241(1):E57-63. doi: 10.1152/ajpendo.1981.241.1.E57.

Abstract

The mechanism of change in low-density lipoprotein (LDL) levels by diets differing in fat saturation have been studied. Turnover of 125I-LDL was measured in eight subjects with type II hyperlipoproteinemia and in seven normal control subjects during two dietary periods containing 40% of calories as either safflower oil (polyunsaturated fat, PSF) or as lard (saturated fat, SF). Higher levels of LDL apoprotein and LDL-cholesterol were observed in both groups on saturated fat. Subjects with elevated LDL levels (type II) showed a more marked effect of polyunsaturated fat with 25% lower LDL production rate as compared to a reduction of only 10% for the control group. On the PSF diet, the production rate in type II (12.7 mg.kg-1.day-1) was not statistically different from normal subjects (10.5 mg.kg-1.day-1). On this diet, the higher levels of LDL cholesterol in the type II subjects (as compared to controls) were due to a lower fractional clearance rate, mean of 0.27/day compared to a mean of 0.39/day for the normal subjects. Although individuals with type II hyperlipoproteinemia may have a primary clearance defect, the major reduction in plasma cholesterol concentrations achieved with a diet high in polyunsaturated fat can be attributed to a significantly lower LDL production.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Cholesterol / blood
  • Cholesterol, LDL
  • Dietary Fats / pharmacology*
  • Fatty Acids, Unsaturated / pharmacology
  • Female
  • Humans
  • Hyperlipoproteinemias / blood
  • Lipoproteins, HDL / blood
  • Lipoproteins, LDL / blood*
  • Lipoproteins, VLDL / blood
  • Male
  • Middle Aged
  • Phenotype
  • Reference Values
  • Triglycerides / blood

Substances

  • Cholesterol, LDL
  • Dietary Fats
  • Fatty Acids, Unsaturated
  • Lipoproteins, HDL
  • Lipoproteins, LDL
  • Lipoproteins, VLDL
  • Triglycerides
  • Cholesterol