No Effect of High-Dose Vitamin D Supplementation on Glycemic Status or Cardiovascular Risk Factors in Subjects With Prediabetes

• Published in: Diabetes care Vol. 37; no. 8; pp. 2123 - 2131
• Main Authors: Sollid, Stina Therese, Hutchinson, Moira Y.S., Fuskevåg, Ole M., Figenschau, Yngve, Joakimsen, Ragnar M., Schirmer, Henrik, Njølstad, Inger, Svartberg, Johan, Kamycheva, Elena, Jorde, Rolf
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Diabetes Association 01.08.2014
• Subjects: 25-Hydroxyvitamin D 2 - metabolism; Adult; Aged; Aged, 80 and over; Biological and medical sciences; Blood pressure; Blood Pressure - physiology; Calcifediol - metabolism; Cardiovascular disease; Cholecalciferol - administration & dosage; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - prevention & control; Diabetes. Impaired glucose tolerance; Diabetic Angiopathies - prevention & control; Dietary Supplements; Double-Blind Method; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Female; Glucose Intolerance - prevention & control; Glucose Tolerance Test; Glycemic index; Humans; Insulin - metabolism; Insulin resistance; Insulin Resistance - physiology; Lipids - blood; Male; Medical sciences; Metabolic diseases; Metabolism; Middle Aged; Prediabetic State - blood; Prediabetic State - prevention & control; Risk Factors; Vitamin D; Vitamin D - analogs & derivatives; Vitamin D - metabolism; Vitamin D Deficiency - blood; Vitamin D Deficiency - diet therapy; Vitamins - administration & dosage; Young Adult; Human; Nutrition; Vitamin D; Risk factor; Cardiovascular risk; Metabolic diseases; Cardiovascular disease; Supplementation; High dose; Endocrinology; Glycemia
• ISSN: 0149-5992; 1935-5548; 1935-5548
• DOI: 10.2337/dc14-0218

In observational studies, low serum 25-hydroxyvitamin D [25(OH)D] concentrations have been associated with insulin resistance and other risk factors for cardiovascular disease. We present 1-year data from an ongoing 5-year trial in 511 individuals with impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) randomly assigned to 20,000 IU/week vitamin D3 or placebo. An oral glucose tolerance test was performed at baseline and after 1 year. Mean baseline serum 25(OH)D was 59.9 nmol/L and 61.1 nmol/L in the vitamin D and placebo groups, respectively, and increased by 45.8 nmol/L and 3.4 nmol/L, respectively. With adjustment for baseline concentrations, no differences in measures of glucose metabolism, insulin secretion or sensitivity, blood pressure, or hs-CRP were found after 1 year. There was a slight, but significant decrease in total and LDL cholesterol in the vitamin D group compared with the placebo group, but as there was also a decrease in HDL cholesterol, the change in the total/HDL cholesterol ratio did not differ significantly. Only analyzing subjects with 25(OH)D <50 nmol/L did not change the results. This study shows that vitamin D supplementation does not improve glycemic indices, blood pressure, or lipid status in subjects with IFG and/or IGT.