Determinants of vitamin D status in physically active elderly in the Netherlands

PurposeVitamin D deficiencies are common in elderly, which increases the risk for, e.g., bone fractures. Identification of determinants of vitamin D status may provide leads for specific deficiency prevention strategies. Although determinants of vitamin D status have been studied in various populations, this has not been examined in elderly that have a physically active lifestyle.MethodsVitamin D status of 450 physically active elderly who do not use vitamin D supplements was determined and information on possible determinants (demographic, dietary intake and physical activity) was collected around a prolonged four day walking event in July and analyzed in linear regression models.ResultsThe average summertime serum 25(OH)D concentration was 88.822.4 nmol/L. Only 2% of the participants had a 25(OH)D concentration below 50 nmol/L. Dietary intake of vitamin D was 4.0 +/- 1.9 mu g/day, and the participants spent 12.4 +/- 8.6 h/week on outdoor activities. In the multivariate model, lower age (=- 0.48, 95% CI - 0.80 to - 0.16), lower BMI (=- 0.86, 95% CI - 1.62 to -0.10), being a moderate to high drinker versus a non-drinker (=7.97, 95% CI 0.43-15.51) and more outdoor physical activity (=0.25, 95% CI 0.01-0.50) were significantly associated with higher 25(OH)D concentrations.Conclusions In physically active elderly, vitamin D status was very high in summertime, with few deficiencies, suggesting that elderly with a physical active lifestyle might not necessarily need supplements during the summer period. Lower age, lower BMI, higher alcohol intake and more outdoor physical activity had a significant association with vitamin D status.