Vitamin D status in eastern South Dakota.

BACKGROUND: Vitamin D deficiency is prevalent in the general U.S. population. To date, although there are a number of case reports, no studies of the prevalence of vitamin D deficiency in the general population of the upper Midwest have been reported. The present study was undertaken to define the vitamin D status in three groups: healthy working adults, pregnant women and nursing home residents. METHODS: A prospective evaluation of serum vitamin D levels. RESULTS: Seventy-five percent of healthy working adults, 63 percent of nursing home residents and 83 percent of maternity patients had serum calcidiol levels below 32 ng/mL. Mean levels were 26.4 ng/mL, 28.8 ng/mL, and 20.7 ng/mL, respectively. CONCLUSION: Hypovitaminosis D is highly endemic in this region's population; routine supplementation and/or empiric replacement therapy should be considered, especially as a part of routine prenatal care.