Delhi: Vitamin D supplementation over 78 weeks in overweight/obese prediabetic and vitamin D deficient Asian Indian women significantly reduced fat and blood sugar, according to a study by researchers from All India Institute of Medical Sciences (AIIMS) and Diabetes Foundation of India. The study is published in the journal Scientific Reports.
Vitamin D deficiency is increasingly recognized as a global health problem. India, being a country is exposed to adequate sunshine, it is assumed that Indians have adequate vitamin D levels. However, several studies have shown a high prevalence of vitamin D deficiency in the Indian population. Also, there is an association between inadequate vitamin D levels and diabetes, obesity.
Anoop Misra, Diabetes Foundation (India), Safdarjung Development Area, New Delhi, India, and colleagues evaluated the effect of vitamin D supplementation on blood sugar levels and body composition in prediabetic, vitamin D deficient overweight/obese Asian Indian women.
"In women with prediabetes, it is worthwhile to give vitamin D (if deficient) in addition to diet and exercise to revert to normal glucose levels," Dr. Misra told .
This open-label randomized placebo-controlled trial (78 weeks duration) involved 121 females (aged 20–60 years) with prediabetes and vitamin D deficiency. They were randomly allocated to intervention (n=61) and placebo (n=60) groups.
The primary outcome variables were fasting blood glucose (FBG), 2-h blood glucose post-OGTT (2-h BG), hemoglobin A1c (HbA1C), and reversal to normoglycemia.
Key findings of the study included :
There was a significant decrease in FBG [−5.0], 2-h blood glucose post OGTT [−11], hemoglobin A1c [−0.41] and increase in 25(OH) D [7.5] levels in intervention as compared to the placebo group.
Changes in glycemic category based on FBG were as follows; intervention group: normal FBG, 58.6%; impaired fasting glucose (IFG), 39%; and type 2 diabetes mellitus (T2DM), 2.4%; placebo group: normal FBG, 48.8%; IFG, 46.3%; and T2DM, 4.9%.
Changes in category of 2-hour glucose post-OGTT after intervention were as follows; intervention group: normal glucose tolerance (NGT) 51.2% and prediabetes, 48.8%; placebo group: NGT, 43.9%; prediabetes, 53.7% and T2DM, 2.4%.
After intervention, subscapular skinfold (visit Ist compared to visit IIIrd) and suprailiac skinfold (visit IInd compared to visit IIIrd) were significantly lower in the intervention group vs. control group.
The study shows that some patients - who were pre-diabetic and given vitamin D supplements during the trial - reverted to normal glucose levels and body fat also decreased. Whereas, the placebo sample without vitamin D supplements progressed to diabetes.
"We observed a significant reduction in FBG, 2-hour glucose post-OGTT, HbA1c, and truncal subcutaneous fat and reversal to normoglycemia in overweight/obese prediabetic vitamin D deficient Asian Indian women after 78 weeks of vitamin D supplementation," concluded the authors.
"In this robustly conducted randomised controlled trial, we show that obese women, who are prediabetic and also have vitamin D deficiency, benefit from supplementation. Prediabetes reverted to normal glucose regulation in more women in vitamin D group than those who received placebo. This benefit occurred over 18 months. It also lead to decrease in truncal subcutaneous fat (perceived as 'bad fat'). Such a study has not been performed before in India. Also, results are generally contrary to some studies performed in western population. It is likely that vitamin d benefits Indians more than other races," said Dr. Misra.
The study, "Vitamin D Supplementation in Overweight/obese Asian Indian Women with Prediabetes Reduces Glycemic Measures and Truncal Subcutaneous Fat: A 78 Weeks Randomized Placebo-Controlled Trial (PREVENT-WIN Trial)," is published in the journal Scientific Reports.
DOI: 10.1038/s41598-019-56904-y