Salt Lake Tribune
Posted: 02/26/2009 04:47:02 PM MST
An LDS Church-backed study has found a majority of pregnant women don't get enough vitamin D, which means their fetuses are deficient, too. The vitamin is critical for fetal growth, and a lack of it could put them at future risk for a host of diseases, including cancer, diabetes and multiple sclerosis.
Results from the South Carolina-based study could eventually help lead to new recommendations on how much vitamin D pregnant women should take -- and perhaps the development of new multivitamins to meet the need.
Physician Carol Wagner, who will discuss her preliminary findings Friday in Salt Lake City, called the widespread vitamin deficiency an "epidemic." She found 85 percent of study participants had insufficient or deficient levels of the vitamin, which is critical to bone growth, calcium absorption and immunity. She said it's one of the few studies that tracked deficiency levels during pregnancy.
"When you see something like this that's so pervasive, you have to do something about it," she said in an interview Thursday.
Vitamin D deficiency has long been linked to the bone disease rickets. Inadequate amounts have also been shown to increase the risk of osteoporosis, cardiovascular disease, diabetes, autoimmune diseases and colon, prostate and breast cancers.
Wagner's study was funded with $335,000 from the Thrasher Research Fund, which supports research to prevent and treat children's diseases. It is administered by The Church of Jesus Christ of Latter-day Saints.
Typical prenatal vitamins contain 400 international units of the supplement, which has been shown to have little effect on maternal levels. Wagner, a professor at Medical University of South Carolina, is studying whether 2,000 units or 4,000 units is better at reducing pregnancy complications and boosting levels of vitamin D in infants.
Wagner has extensively studied the deficiency in women and children: She was the lead author of 2008 American Academy of Pediatrics' guidelines that say all children and infants, including those breastfed, should have 400 units.
And in a separate study, Wagner is studying whether breastfeeding women should take 6,000 units.
"Babies are born with low levels of vitamin D because their only source is the mother," Wagner said. "If she's deficient, her milk will be deficient [and] the baby will be deficient."
Diet contributes just 10 percent of a person's vitamin D levels. Sun exposure is the main source -- up to 15 minutes of full-body exposure during the summer generates up to 20,000 units for the fair-skinned. Using sunscreen prevents skin cancer but also blocks vitamin D production.
People with darker skin pigmentation typically have lower levels of vitamin D because they need even more sun exposure.
Wagner's study backed that. After screening 500 underserved pregnant women in Eau Claire, S.C., Wagner found vitamin D deficiency varied by ethnicity and race. About 94 percent of black, 78 percent of Latino and 68 percent of white women had insufficient or deficient levels.
The Institute of Medicine is reviewing vitamin D studies and may revise guidelines that recommend 200 units a day for most adults and no more than 2,000 units.