In a study of healthy young adults in the Boston area, vitamin D deficiency was found prevalent irrespective of race and ethnicity. The study was presented at ENDO 2011: the 93rd Annual Meeting & Expo of the Endocrine Society in Boston. As known, vitamin D deficiency is associated with impaired bone mineralization and may be a risk factor for other health conditions. But the prevalence of vitamin D deficiency in healthy young adults had not been well described. Researchers at Massachusetts General Hospital in Boston measured serum 25-hydroxyvitamin D (25OHD) by chemiluminescent immunoassay in an ethnically diverse cohort of 634 adults aged 18 to 50 from January 2006 through April 2008. The subjects had no known health conditions that might affect vitamin D absorption or metabolism and were excluded if taking >2000 IUs of vitamin D daily. Following data analysis, 39% of subjects were found to have vitamin D deficiency (serum 25OHD </=20 ng/mL), and 7% had severe deficiency (25OHD </=10 ng/mL). Predictors of lower serum 25OHD values in univariate analyses included male gender; black, Asian, or “other” race; and lack of multivitamin use (P<0.001 for all predictors). Sixteen percent of multivitamin users had deficiency compared with 42% of non-users (risk ratio 2.6, P<0.001).In addition to their data analysis, the researchers developed a clinical score that may guide decisions regarding screening for deficiency. It awaits validation in future prospective studies. In other research presented at ENDO 2011, Australian investigators reported their finding that vitamin D deficiency was common in pregnancy but not associated with spontaneous miscarriage. Such had been hypothesized due to its implication in immune regulation.