Taking care of a wee one this winter? You may want to talk to your doctor about supplementing with vitamin D. Research has found babies born during the winter months may have markers of improved bone health if their mothers take vitamin D. The study was published in Lancet Diabetes & Endocrinology and included 737 pregnant women ages 18 or older who had vitamin D blood concentrations between 25 nmol/L and 100 nmol/L when they enrolled in the study. The women were randomly assigned to receive either 1,000 IU per day of cholecalciferol (vitamin D3) or a placebo from the time of enrollment (before the 17th week of pregnancy) until delivery. At weeks 14 and 34 of pregnancy, researchers took blood samples to measure the women’s vitamin D concentrations and collected information about diet, smoking habits, change in health status, and other factors. Researchers then ran a test on each newborn within two weeks of birth to assess bone mineral content and other measures of body composition. At the end of the study, researchers found:

• Overall, there were no differences in bone mineral content or other measures of body composition between newborns born to mothers supplementing with vitamin D and those not supplementing with vitamin D.
• A second analysis that included season of birth, however, revealed that winter babies born to mothers receiving vitamin D had higher bone mineral content, whole-body bone area, bone density, and body fat mass than winter babies born to mothers receiving a placebo.
• Mothers who supplemented with vitamin D were less likely to have vitamin D insufficiency at 34 weeks than mothers taking a placebo.

While other research has provided conflicting data on the significance of a mother’s vitamin D levels on their child’s bone development, these results suggest maintaining vitamin D sufficiency in pregnancy may result in higher bone mineral content in winter babies. Other research has further suggested that bone status at birth may be a predictor of bone health later in life. As for getting vitamin D, sunlight is a major source for mothers, babies, and others, but during the dark days of winter, other sources are necessary. There are only a few foods that naturally contain vitamin D, but you can also get it from fortified foods like cereal and milk. A supplement can also be a good way to get a boost of vitamin D.

Source: Lancet Diabetes & Endocrinology