High-dose vitamin D does not improve insulin resistance in older adults with … – Healio
Older adults assigned high-dose vitamin D supplementation for 1 year showed no differences in measures of insulin resistance when compared with older adults assigned a lower dose of vitamin D, according to recent study findings presented at The American Society for Bone and Mineral Research Annual Meeting.
“High dose vitamin D did not improve insulin resistance in elderly overweight individuals,” Ghada El-Hajj Fuleihan, MD, MPH, of American University of Beirut-Medical Center in Lebanon, and colleagues wrote. “Regardless of vitamin D dose, an unexpected rise in fasting glucose, that correlated with the rise in [vitamin D levels], and exceeded the anticipated rise in [fasting blood sugar] in an aging, overweight population, was observed.”
Fuleihan and colleagues analyzed data from 222 adults (mean age, 71 years; mean BMI, 30 kg/m²; 55% women) without diabetes participating in a 1-year, double-blind, randomized controlled trial. Researchers randomly assigned participants to 1,000 mg calcium citrate and the equivalent of either 600 IU or 3,500 IU vitamin D3 daily.
Hormone levels and serum 25-hydroxyvitamin D were measured at baseline, 3, 6, and 12 months.
Within the cohort, 69% of participants had impaired fasting glucose or abnormal HbA1c; 45% of participants were taking antihypertensive medications; 30% were taking lipid-lowering medications. After 1 year, vitamin D levels in the low-dose group rose from 20 ng/mL to 26 ng/mL; levels in the high-dose group rose from 20.9 ng/mL to 35.9 ng/mL. Researchers noted a significant rise in fasting g glucose within each group, which was not explained by either statins or a drift in laboratory performance over the study period.
“There were no detectable differences in [fasting blood glucose], nor in any of the indices of insulin resistance, between the two groups at 1 year,” the researchers wrote. “In the multivariate analyses, BMI, but not vitamin D treatment or age, predicted insulin sensitivity indices at 1 year.” – by Regina Schaffer
Fuleihan G, et al. Abstract 1091. Presented at: The American Society for Bone and Mineral Research Annual Meeting; Oct. 9-12, 2015; Seattle.
Disclosure: Fuleihan reports no relevant financial disclosures.