Vitamin D is involved in the process by which your body makes use of calcium. It is sometimes called “the sunshine vitamin” because in the presence of sun your body makes its own vitamin D from a substance already present in your skin. There are few sources of preformed vitamin D, but fortified milks (which contain 400 IU per quart) are the most reliable source. Poor intake of the performed vitamin, coupled with low sunlight exposure may cause problems, particularly with the enamel development of baby’s teeth. If you do not use commercial milk or milk products and are only infrequently exposed to sunlight, you should discuss the use of a vitamin D supplement with your clinician.

Studies conducted in the U.K. suggest that mothers who take supplemental vitamin D while pregnant are more likely to have children with higher bone mineral content as they age. The study measured bone mineral density or BMD in 9-year old children whose mothers supplemented with vitamin D throughout their pregnancy.

More vitamin D equates to better bone strength and a reduced risk for bone fractures resulting from bone thinning or weakening diseases like osteoporosis. The study appearing in a recent issue of the Lancet suggests that it is vital that women receive enough vitamin D to ensure the health and well-being of their children's bones later in life.

The Role of Vitamin D and Your Health

Most people assume that calcium is the most important vitamin or nutrient for bone health. Realistically speaking however, vitamin D is just as important. Found in common foods like egg yolks, certain fishes, liver and fortified foods including milk, vitamin D works in combination with other vitamins and minerals to ensure healthy bone growth. Vitamin D helps the body absorb valuable nutrients like calcium and phosphorus.

Researchers discovered that many pregnant women have a vitamin D deficiency, as do the elderly. The study published in the Lancet suggests that early postnatal development and intrauterine development contribute to a person's overall bone mineral accrual later in life. This in turn may influence their risk of osteoporosis.

Vitamin D Deficiencies

People can get Vitamin D by exposure to direct sunlight. Typically most people will receive enough vitamin D simply through routine exposure, however recent skin cancer concerns are causing people to cover up (rightly so) under the sun. This can reduce the vitamin D the skin produces resulting from sun exposure.

Hence, those with light colored skin may be more at risk for deficiencies. They often apply sunscreen to protect from skin cancer. The sun ultimately provides one source of vitamin D however; hence this population may be more at risk for shortages. Others simply don't eat enough of vitamin D rich or fortified foods. Studies also confirm that most people do not get enough vitamin D from their diet alone.

The study conducted of pregnant women included more than 150 women delivering babies in the early 90s. The researchers used blood tests to find out the levels of vitamin D in pregnant women. The study revealed that nearly 31% of women had a slight vitamin D deficiency while 18% had a significant vitamin D deficiency.

The researchers followed the infants into early childhood. By age nine the children received BMD scans, revealing that children whose mothers had vitamin D deficiencies during pregnancy had less BMD than those whose mothers had enough vitamin D circulating in their system while pregnant.

Are Vitamin D Supplements Necessary?

The researchers stressed how important satisfactory vitamin D intake is during pregnancy. The studies suggest that vitamin D supplementation during pregnancy may result in stronger bones in children later in life.

The study suggests that more long-term studies are necessary to assess the role vitamin D plays in bone development and growth of children while in utero. Women who enjoy their last trimester during winter months may be more at risk for vitamin D deficiencies, in part due to less exposure to sunlight and lower than average levels of sunlight. These women may need vitamin D supplements to promote healthy bone development in their babies.

Vitamin D supplementation is not only good for babies however, but also good for their mothers. Check with your doctor to ensure that you are receiving enough vitamin D supplementation during your pregnancy. Your health and that of your unborn baby may depend on it!