Daily consumption of vitamin D– or vitamin D + calcium–fortified yogurt drink improved glycemic control in patients with type 2 diabetes: a randomized clinical trial

• Published in: The American journal of clinical nutrition 2011-04, Vol.93 (4), p.764-771
• Main Authors: Nikooyeh, Bahareh, Neyestani, Tirang R, Farvid, Maryamosadat, Alavi-Majd, Hamid, Houshiarrad, Anahita, Kalayi, Ali, Shariatzadeh, Nastaran, Gharavi, A’azam, Heravifard, Soudabeh, Tayebinejad, Nima, Salekzamani, Shabnam, Zahedirad, Malihe
• Format: Article
• Language: English
• Subjects: Adult; Biological and medical sciences; Blood Glucose - metabolism; Body Composition; Body Mass Index; Calcium; Calcium - pharmacology; Calcium - therapeutic use; Cholecalciferol - pharmacology; Cholecalciferol - therapeutic use; Clinical trials; Comparative analysis; Diabetes; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - drug therapy; Effects; Fasting; Feeding. Feeding behavior; Female; Food, Fortified; Fundamental and applied biological sciences. Psychology; Glucose; Glycated Hemoglobin - metabolism; Humans; Insulin Resistance; Male; Middle Aged; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vitamin D; Vitamin D - blood; Vitamins - blood; Vitamins - pharmacology; Vitamins - therapeutic use; Waist Circumference; Yogurt
• ISSN: 0002-9165; 1938-3207
• DOI: 10.3945/ajcn.110.007336

Background: Low serum concentrations of 25-hydroxyvitamin D [25(OH)D] have been associated with impaired glucose tolerance and diabetes. Objective: This study aimed to compare the effects of daily intake of vitamin D– or vitamin D3 + calcium–fortified yogurt drink on glycemic status in subjects with type 2 diabetes (T2D). Design: Ninety diabetic subjects were randomly allocated to 3 groups to consume plain yogurt drink (PY; containing no vitamin D and 150 mg Ca/250 mL), vitamin D–fortified yogurt drink (DY; containing 500 IU vitamin D3 and 150 mg Ca/250 mL), or vitamin D + calcium–fortified yogurt drink (DCY; containing 500 IU vitamin D3 and 250 mg Ca/250 mL) twice per day for 12 wk. Fasting serum glucose (FSG), glycated hemoglobin (Hb A1c), homeostasis model assessment of insulin resistance (HOMA-IR), serum lipid profile, and percentage fat mass (FM) were assessed before (baseline) and after the intervention. Results: In both the DY and DCY groups, mean serum 25(OH)D3 improved (+32.8 ± 28.4 and +28.8 ± 16.1 nmol/L, respectively; P < 0.001 for both), but FSG [−12.9 ± 33.7 mg/dL (P = 0.015) and −9.6 ± 46.9 mg/dL (P = 0.035)], Hb A1c [−0.4 ± 1.2% (P < 0.001) and −0.4 ± 1.9% (P < 0.001)], HOMA-IR [−0.6 ± 1.4 (P = 0.001) and −0.6 ± 3.2 (P < 0.001)], waist circumference (−3.6 ± 2.7 and −2.9 ± 3.3; P < 0.001 for both), and body mass index [in kg/m2; −0.9 ± 0.6 (P < 0.001) and −0.4 ± 0.7 (P = 0.005)] decreased significantly more than in the PY group. An inverse correlation was observed between changes in serum 25(OH)D3 and FSG (r = −0.208, P = 0.049), FM (r = −0.219, P = 0.038), and HOMA-IR (r = −0.219, P = 0.005). Conclusion: Daily intake of a vitamin D–fortified yogurt drink, either with or without added calcium, improved glycemic status in T2D patients. This trial was registered at clinicaltrials.gov as NCT01229891.