title: High saturated fatty acid intake induces insulin secretion by elevating gastric inhibitory polypeptide levels in healthy individuals.
abstract: Insulin resistance is central to the etiology of the metabolic syndrome cluster of diseases. Evidence suggests that a high-fat diet is associated with insulin resistance, which may be modulated by dietary fatty acid composition. We hypothesized that high saturated fatty acid intake increases insulin and gastric inhibitory polypeptide (GIP) secretion. To clarify the effect of ingested fatty acid composition on glucose levels, we conducted an intervention study to investigate the insulin and plasma GIP responses in 11 healthy women, including a dietary control. Subjects were provided daily control meals (F-20; saturated fatty acids/monounsaturated fatty acids/polyunsaturated fatty acids [S/M/P] ratio, 3:4:3) with 20 energy (E) % fat, followed by 2 isoenergetic experimental meals for 7 days each. These meals comprised 60 E% carbohydrate, 15 E% protein, and 30 E% fat (FB-30; high saturated fatty acid meal; S/M/P, 5:4:1; F-30: reduced saturated fatty acid meal; S/M/P, 3:4:3). On the second day of the F-20 and the last day of F-30 and FB-30, blood samples were taken before and 30, 60, and 120 minutes after a meal tolerance test. The plasma glucose responses did not differ between F-20 and FB-30 or F-30. However, insulin levels were higher after the FB-30 than after the F-20 (P < .01). The GIP response after the FB-30 was higher than that after the F-30 (P < .05). In addition, the difference in the incremental GIP between FB-30 and F-30 correlated significantly and positively with that of the insulin. These results suggest that a high saturated fatty acid content stimulates postprandial insulin release via increased GIP secretion.
authors.affiliation: Faculty of Nutritional Sciences, Nakamura Gakuen University, Fukuoka, Japan. Electronic address: itohk@k7.dion.ne.jp.
authors.forename: Kazue
authors.initials: K
authors.lastname: Itoh
authors.affiliation: Faculty of Nutritional Sciences, Nakamura Gakuen University, Fukuoka, Japan.
authors.forename: Ririko
authors.initials: R
authors.lastname: Moriguchi
authors.affiliation: Department of Internal Medicine, Akita University, Akita City, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Yamada
authors.affiliation: Department of Public Health, Chiba University, Chiba, Japan.
authors.forename: Misuzu
authors.initials: M
authors.lastname: Fujita
authors.affiliation: Faculty of Nutritional Sciences, Nakamura Gakuen University, Fukuoka, Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Yamato
authors.affiliation: Faculty of Nutritional Sciences, Nakamura Gakuen University, Fukuoka, Japan.
authors.forename: Masayo
authors.initials: M
authors.lastname: Oumi
authors.affiliation: Department of Biomedical Sciences, Panum Institute, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jens Juul
authors.initials: JJ
authors.lastname: Holst
authors.affiliation: Kansai Electric Power Hospital, Osaka, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Seino
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism*; D059305:Diet, High-Fat; D004041:Dietary Fats / Q000494:pharmacology*; D005227:Fatty Acids / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D005749:Gastric Inhibitory Polypeptide / Q000037:antagonists & inhibitors*; D006801:Humans; D007328:Insulin / Q000097:blood*; D012016:Reference Values; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D004041:Dietary Fats; D005227:Fatty Acids; D007328:Insulin; D005749:Gastric Inhibitory Polypeptide
keywords: Diet; Gastric inhibitory polypeptide; Glucose; Human; Insulin; Intervention study; Saturated fatty acids