title: Glucose Metabolism Effects of Vitamin D in Prediabetes: The VitDmet Randomized Placebo-Controlled Supplementation Study.
abstract: Epidemiological evidence suggests a role for vitamin D in type 2 diabetes prevention. We investigated the effects of vitamin D3 supplementation on glucose metabolism and inflammation in subjects with prediabetes. A 5-month randomized, double-blind, placebo-controlled intervention with three arms (placebo, 40 μg/d, or 80 μg/d vitamin D3) was carried out among sixty-eight overweight (BMI 25-35) and aging (≥60 years) subjects from Finland, with serum 25-hydroxyvitamin D3 [25(OH)D3] < 75 nmol/L and either impaired fasting glucose or impaired glucose tolerance. Analyses included 66 subjects who completed the trial. Glucose metabolism was evaluated by fasting and 2-hour oral glucose tolerance test-derived indices and glycated hemoglobin. Inflammation was evaluated by high-sensitive C-reactive protein and five cytokines. Although a dose-dependent increase in serum 25(OH)D3 over the supplementation period was observed (P trend < 0.001), there were no other statistically significant differences in changes in the 13 glucose homeostasis indicators between the study groups other than increase in the 120 min glucose concentration (P trend = 0.021) and a decreasing trend both in 30 min plasma insulin (P trend = 0.030) and glycated hemoglobin (P trend = 0.024) concentrations. A borderline statistically significant decreasing trend in interleukin-1 receptor antagonist concentration was observed (P = 0.070). Vitamin D3 supplementation does not improve glucose metabolism in ageing subjects with prediabetes but may have modest anti-inflammatory effects.
authors.affiliation: Unit of Public Health, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Tomi-Pekka
authors.initials: TP
authors.lastname: Tuomainen
authors.affiliation: Unit of Public Health, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Jyrki K
authors.initials: JK
authors.lastname: Virtanen
authors.affiliation: Unit of Public Health, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland ; The Unit of Clinical Nutrition, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Sari
authors.initials: S
authors.lastname: Voutilainen
authors.affiliation: Unit of Public Health, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Tarja
authors.initials: T
authors.lastname: Nurmi
authors.affiliation: Unit of Public Health, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Jaakko
authors.initials: J
authors.lastname: Mursu
authors.affiliation: The Unit of Clinical Nutrition, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Vanessa D F
authors.initials: VD
authors.lastname: de Mello
authors.affiliation: The Unit of Clinical Nutrition, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland ; Institute of Clinical Medicine, Internal Medicine, Kuopio University Hospital (KYS), P.O. Box 100, 70029 Kuopio, Finland.
authors.forename: Ursula
authors.initials: U
authors.lastname: Schwab
authors.affiliation: The Unit of Clinical Nutrition, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Martti
authors.initials: M
authors.lastname: Hakumäki
authors.affiliation: Department of Clinical Chemistry, Institute of Clinical Medicine, University of Eastern Finland and Eastern Finland Laboratory Centre, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Kari
authors.initials: K
authors.lastname: Pulkki
authors.affiliation: The Unit of Clinical Nutrition, The Institute of Public Health and Clinical Nutrition, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland.
authors.forename: Matti
authors.identifier: 0000-0001-6052-2001
authors.initials: M
authors.lastname: Uusitupa
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D002097:C-Reactive Protein / Q000378:metabolism*; D002112:Calcifediol / Q000097:blood*; D002762:Cholecalciferol / Q000627:therapeutic use*; D016207:Cytokines / Q000378:metabolism*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000150:complications / Q000378:metabolism*; D011236:Prediabetic State / Q000150:complications / Q000188:drug therapy* / Q000378:metabolism; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000378:metabolism; D016896:Treatment Outcome; D014815:Vitamins / Q000627:therapeutic use*
chemical_list: D001786:Blood Glucose; D016207:Cytokines; C508585:IL1B protein, human; C507763:IL1RN protein, human; C508600:IL6 protein, human; D053590:Interleukin 1 Receptor Antagonist Protein; D053583:Interleukin-1beta; D015850:Interleukin-6; D047889:Receptors, Tumor Necrosis Factor, Type II; D014815:Vitamins; D002762:Cholecalciferol; D002097:C-Reactive Protein; D002112:Calcifediol