Differential effects of saturated and monounsaturated fatty acids on postprandial lipemia and incretin responses in healthy subjects.
BACKGROUND
Elevations of postprandial triacylglycerol-rich plasma lipoproteins and suppressions of HDL-cholesterol concentrations are considered potentially atherogenic. Long-term studies have shown beneficial effects of monounsaturated fatty acids (eg, oleic acid) on fasting lipid and lipoprotein concentrations in humans. A direct stimulatory effect of oleic acid on the secretion of glucagon-like peptide 1 (GLP-1) was shown in animal studies.


OBJECTIVE
We compared the postprandial responses of glucose, insulin, fatty acids, triacylglycerol, gastric inhibitory polypeptide (GIP), and GLP-1 to test meals rich in saturated and monounsaturated fatty acids.


METHODS
Ten young, lean, healthy persons ingested 3 meals: an energy-free soup consumed with 50 g carbohydrate (control meal), the control meal plus 100 g butter, and the control meal plus 80 g olive oil. Triacylglycerol and retinyl palmitate responses were measured in total plasma, in a chylomicron-rich fraction, and in a chylomicron-poor fraction.


RESULTS
No significant differences in glucose, insulin, or fatty acid responses to the 2 fat-rich meals were seen. Plasma triacylglycerol responses were highest after the butter meal, with chylomicron triacylglycerol rising 2.5-5-fold. Retinyl palmitate responses were higher and more prolonged after the butter meal than after the control and olive oil meals, whereas both postprandial HDL-cholesterol concentrations and GLP-1 and GIP responses were higher after the olive oil meal than after the butter meal.


CONCLUSIONS
Olive oil induced lower triacylglycerol concentrations and higher HDL-cholesterol concentrations than butter, without eliciting differences in concentrations of glucose, insulin, or fatty acids. Furthermore, olive oil induced higher concentrations of GLP-1 and GIP than did butter, which may point to a relation between fatty acid composition, incretin responses, and triacylglycerol metabolism in the postprandial phase.
Thomsen
C
C
Aarhus Amtssygehus, Aarhus University Hospital, Denmark. claus.thomsen@dadlnet.dk
Rasmussen
O
O
Lousen
T
T
Holst
J J
JJ
Fenselau
S
S
Schrezenmeir
J
J
Hermansen
K
K
D000328:Adult; D001786:Blood Glucose / Q000187:drug effects; D002079:Butter; D008076:Cholesterol, HDL / Q000097:blood*; D004032:Diet; D004041:Dietary Fats / Q000008:administration & dosage / Q000494:pharmacology*; D005227:Fatty Acids / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D005229:Fatty Acids, Monounsaturated / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D005260:Female; D005749:Gastric Inhibitory Polypeptide / Q000097:blood; D005934:Glucagon; D052216:Glucagon-Like Peptide 1; D004763:Glucagon-Like Peptides; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D018377:Neurotransmitter Agents / Q000097:blood*; D000069463:Olive Oil; D010446:Peptide Fragments / Q000097:blood*; D010455:Peptides / Q000097:blood; D010938:Plant Oils; D019518:Postprandial Period; D014280:Triglycerides / Q000097:blood*
D001786:Blood Glucose; D008076:Cholesterol, HDL; D004041:Dietary Fats; D005227:Fatty Acids; D005229:Fatty Acids, Monounsaturated; D007328:Insulin; D018377:Neurotransmitter Agents; D000069463:Olive Oil; D010446:Peptide Fragments; D010455:Peptides; D010938:Plant Oils; D014280:Triglycerides; C055453:glucagon-like peptide 1 (7-36)amide; D005749:Gastric Inhibitory Polypeptide; D004763:Glucagon-Like Peptides; D002079:Butter; D052216:Glucagon-Like Peptide 1; D005934:Glucagon