Palmitic acid in the sn-2 position of dietary triacylglycerols does not affect insulin secretion or glucose homeostasis in healthy men and women

Eur J Clin Nutr. 2014 Sep;68(9):1036-41. doi: 10.1038/ejcn.2014.141. Epub 2014 Jul 23.

Abstract

Background/objectives: Dietary triacylglycerols containing palmitic acid in the sn-2 position might impair insulin release and increase plasma glucose.

Subjects/methods: We used a cross-over designed feeding trial in 53 healthy Asian men and women (20-50 years) to test this hypothesis by exchanging 20% energy of palm olein (PO; control) with randomly interesterified PO (IPO) or high oleic acid sunflower oil (HOS). After a 2-week run-in period on PO, participants were fed PO, IPO and HOS for 6 week consecutively in randomly allocated sequences. Fasting (midpoint and endpoint) and postprandial blood at the endpoint following a test meal (3.54 MJ, 14 g protein, 85 g carbohydrate and 50 g fat as PO) were collected for the measurement of C-peptide, insulin, glucose, plasma glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1, lipids and apolipoproteins; pre-specified primary and secondary outcomes were postprandial changes in C-peptide and plasma glucose.

Results: Low density lipoprotein cholesterol was 0.3 mmol/l (95% confidence interval (95% CI)) 0.1, 0.5; P<0.001) lower on HOS than on PO or IPO as predicted, indicating good compliance to the dietary intervention. There were no significant differences (P=0.58) between diets among the 10 male and 31 female completers in the incremental area under the curve (0-2 h) for C-peptide in nmol.120 min/l: GM (95% CI) were PO 220 (196, 245), IPO 212 (190, 235) and HOS 224 (204, 244). Plasma glucose was 8% lower at 2 h on IPO vs PO and HOS (both P<0.05).

Conclusion: Palmitic acid in the sn-2 position does not adversely impair insulin secretion and glucose homeostasis.

Publication types

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

MeSH terms

  • Adult
  • Area Under Curve
  • Arecaceae / chemistry
  • Blood Glucose / metabolism*
  • C-Reactive Protein / metabolism
  • Cholesterol, LDL / blood
  • Cross-Over Studies
  • Diet*
  • Dietary Fats / adverse effects*
  • Dietary Fats / pharmacology
  • Esterification
  • Female
  • Humans
  • Insulin / metabolism*
  • Insulin Secretion
  • Male
  • Middle Aged
  • Oleic Acid / pharmacology
  • Palm Oil
  • Palmitic Acid / adverse effects*
  • Plant Oils / adverse effects*
  • Plant Oils / pharmacology
  • Sunflower Oil
  • Triglycerides / adverse effects*
  • Young Adult

Substances

  • Blood Glucose
  • Cholesterol, LDL
  • Dietary Fats
  • Insulin
  • Plant Oils
  • Sunflower Oil
  • Triglycerides
  • Oleic Acid
  • Palmitic Acid
  • Palm Oil
  • C-Reactive Protein

Associated data

  • ISRCTN/ISRCTN16669399