Vitamin D Supplementation and Glycemic Outcomes

Effect of Treating Vitamin D Deficiency on Glucose Homeostasis and Metabolic Markers in Apparently Healthy, Young or Aged, Normal-weight or Obese Lebanese People

The investigators examined the effect of vitamin D supplementation on glucose homeostasis and metabolic markers in healthy normal weight and overweight young subjects and healthy normal-weight and overweight elderly subjects living in Beirut, Lebanon.

A low serum 25-hydroxyvitamin D (25(OH)D) concentration has been shown to correlate with higher fasting blood glucose (FBG) and insulin levels and other metabolic abnormalities like dyslipidemia. Previous studies suggest that vitamin D supplementation is able to improve insulin sensitivity and metabolic markers. The aim of the study was to investigate the effect of vitamin D supplementation on glucose homeostasis and metabolic markers in healthy normal weight and overweight young subjects and healthy normal-weight and overweight elderly subjects living in Beirut, Lebanon. Participants (n= 180; 93 men and 87 women) deficient in vitamin D were recruited from Saint Charles Hospital, Beirut, Lebanon. Four groups were recruited: normal-weight adults (n=30, age ≤ 65 years and BMI < 25 kg/m²), overweight adults (n=30, age ≤ 65 years and BMI ≥ 25 kg/m²), normal-weight elderly (n=60, age ≥ 65 years and BMI < 25 kg/m²) and overweight elderly (n=60, age ≥ 65 years and BMI ≥ 25 kg/m²). Participants received a supplement of 10,000 IU cholecalciferol to be taken three times per week for a period of 6 months. Glucose homeostasis and metabolic markers were measured at start of treatment, at 3 months and at 6 months.

normal-weight adult subjects (n=30, age ≤ 65 years and BMI ≤ 25 kg/m²) All assigned patients received a supplement of 10,000 IU cholecalciferol (Euro-Pharm International, Canada) to be taken three times per week. The treatment was led for a period of 6 months.

overweight adult subjects (n=30, age ≤ 65 years and BMI ≥ 25 kg/m²) All assigned patients received a supplement of 10,000 IU cholecalciferol (Euro-Pharm International, Canada) to be taken three times per week. The treatment was led for a period of 6 months.

normal-weight elderly (n=60, age ≥ 65 years and BMI ≤ 25 kg/m²) All assigned patients received a supplement of 10,000 IU cholecalciferol (Euro-Pharm International, Canada) to be taken three times per week. The treatment was led for a period of 6 months.

overweight elderly (n=60, age ≥ 65 years and BMI ≥ 25 kg/m²) All assigned patients received a supplement of 10,000 IU cholecalciferol (Euro-Pharm International, Canada) to be taken three times per week. The treatment was led for a period of 6 months.

All assigned patients received a supplement of 10,000 IU cholecalciferol (Euro-Pharm International, Canada) to be taken three times per week. The treatment was led for a period of 6 months.

Inclusion Criteria: Participants with no medical history of congestive heart failure, acute heart insufficiency and renal failure were included Exclusion Criteria: Participants with medical history of congestive heart failure, acute heart insufficiency and renal failure were excluded

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Pittas AG, Lau J, Hu FB, Dawson-Hughes B. The role of vitamin D and calcium in type 2 diabetes. A systematic review and meta-analysis. J Clin Endocrinol Metab. 2007 Jun;92(6):2017-29. doi: 10.1210/jc.2007-0298. Epub 2007 Mar 27.