Effect of synthetic triglycerides of myristic, palmitic, and stearic acid on serum lipoprotein metabolism

Eur J Clin Nutr. 1999 Aug;53(8):597-605. doi: 10.1038/sj.ejcn.1600815.


Objectives: To determine relative effects of diets high in synthetic sources of myristic (14:0), palmitic (16:0) or stearic (18:0) acid on concentrations and metabolism of serum lipoproteins.

Design: Eighteen healthy women participated in a three-way cross-over study for five week periods separated by seven week washout periods, diets were assigned in random order.

Subjects: Premenopausal women, not on medication, were from three races (Caucasian, African-American, Asian) and four apolipoprotein E phenotype groups (3/3, 3/2, 4/3, and 4/2).

Intervention: During the first week the subjects consumed a baseline diet providing 11 energy (en)% saturated fat, 10en% polyunsaturated fat and 14en% monounsaturated fat. Followed by test diets with 19en% saturated fat (including 14en% test saturated fatty acid), 3en% polyunsaturated fat, and 14en% monounsaturated fat for four weeks. Synthetic fats (trimyristin, tripalmitin, and tristearin) were used in blends with natural fats and oils.

Results: Mean concentrations of serum total, esterified and LDL cholesterol were significantly lower after 18:0 than after 16:0 (n = 16-18, P < 0.01 for treatment effect). Myristic acid (14:0) had an intermediate effect. Receptor-mediated degradation of 125I-LDL in mononuclear cells obtained from the subjects was lower after 16:0 than after 14:0 and 18:0 (n = 16-18, P=0.05 for treatment effect). Differences in the digestibilities of the fats were not a major factor in the results. Strong cholesterolemic responses to the 16:0 diet were partly explained by apoE phenotype.

Conclusions: As noted previously, stearic acid was neutral compared to 14:0 and 16:0. In contrast to studies involving natural fats, 14:0, fed as a synthetic triglyceride, was less cholesterolemic than 16:0 in a majority of subjects. ApoE phenotype influenced the cholesterolemic response particularly when diets high in 16:0 were eaten.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Apolipoproteins E / genetics
  • Cholesterol / blood*
  • Cholesterol / metabolism
  • Cross-Over Studies
  • Dietary Fats / metabolism*
  • Fat Substitutes / metabolism*
  • Fatty Acids / metabolism
  • Female
  • Humans
  • Leukocytes, Mononuclear / metabolism
  • Lipoproteins / blood
  • Lipoproteins / metabolism*
  • Myristic Acid / metabolism
  • Palmitic Acid / metabolism
  • Phenotype
  • Receptors, LDL / metabolism
  • Stearic Acids / metabolism
  • Triglycerides / metabolism*


  • Apolipoproteins E
  • Dietary Fats
  • Fat Substitutes
  • Fatty Acids
  • Lipoproteins
  • Receptors, LDL
  • Stearic Acids
  • Triglycerides
  • Myristic Acid
  • trimyristin
  • Palmitic Acid
  • stearic acid
  • Cholesterol
  • tripalmitin
  • tristearin