Calcium Intake and 25-hydroxyvitamin D are Associated with Hyperglycemia in an Adult South Florida Population
Abstract Number: 0068-OR
Authors: HERMES FLOREZ, ANA APAZA, ANGEL R. ALEJANDRO, ANDREA SOSA, MISHA DENHAM, BRUCE HOLLIS, BERNARD ROOS, SILVINA LEVIS, Miami, FL, Charleston, SC
Results: Previous studies have shown a relationship between low levels of 25-hydroxy-vitamin D (25-OH-VitD) and glucose intolerance, but the effect that calcium intake has on this relation is less clear. Therefore we evaluated the association of daily calcium intake and hypovitaminosis D with fasting hyperglycemia (serum blood glucose ≥126 mg/dl) in 168 participants (63.1% female and 72% Hispanics) aged 56.1 ± 11.8 years and with a body mass index (BMI) of 30.5 ± 6.4 kg/m², recruited from an internal medicine clinic at a local hospital in South Florida. Calcium and vitamin D intakes were estimated based on the assessment of supplement use together with a validated food frequency questionnaire. A sun exposure questionnaire was used to determine the amount of sunlight received in the week before the study visit. Sufficient total calcium intake (≥ 1g/day) was observed in 41.9% and 58.4% of those with and without fasting hyperglycemia, respectively (p=0.06). Hypovitaminosis D (25-OH-VitD<70 nmol/L) was more frequent in those with (86%) compared to those without (69.6%) fasting hyperglycemia (p=0.03). After adjusting for demographic variables, sun exposure, vitamin D intake, BMI, and hypertriglyceridemia, hypovitaminosis D was associated with higher risk (OR= 2.7; 95%C.I.:1.02-7.2) of fasting hyperglycemia while sufficient total calcium intake was associated with lower risk (OR= 0.46; 95% C.I.:0.22-0.97). These results suggest that 25-OH-VitD levels and daily calcium intake are factors associated with hyperglycemia in subjects living in an area with year-round sunny weather. Further studies are warranted to assess the potential benefits of providing sufficient calcium intake and keeping normal vitamin D levels in those with or at higher risk for diabetes.