(ARA) – You take her to regular checkups, monitor her nutrition, provide plenty of cuddle time and stimulation, and keep her out of the sun. But is your newborn really getting everything she needs to thrive? More likely than not, she is not getting enough vitamin D, according to studies published by a leading group of doctors.

Also known as the “sunshine vitamin,” vitamin D supports the growth of healthy bones in infants and assists with maintaining functions of their brain, heart and various muscle tissues. Vitamin D deficiency can lead to rickets, a disorder that weakens the bones and becomes apparent during infancy or childhood.

“Vitamin D is not only important in bone health, but emerging data support its role in maintaining our immunity and preventing diseases such as cancer and diabetes. Unfortunately, many infants are not receiving adequate levels of vitamin D from breast milk, formula, or synthesis from sunlight,” says Dr. Scott Cohen, a pediatrician and author of the book “Eat, Sleep, Poop: A Common Sense Guide to Your Child’s First Year.”

For many people, exposure to sunlight is the body’s way of producing vitamin D. But many others, including children being protected from the sun or those with darker skin, need supplemental vitamin D.

In 2008 the American Academy of Pediatricians (AAP) revised its recommendations regarding vitamin D, saying that all children, including newborns, should receive 400 IU a day of vitamin D – double the previously recommended level. Follow-up studies published this year in the organization’s scientific journal, Pediatrics, showed that most children are not receiving vitamin D levels that meet the new 2008 recommendations.

According to data reported in the two studies published in the journal Pediatrics this year, less than 13 percent of infants exclusively breastfed were meeting the daily recommendation of vitamin D. Yet less than 16 percent of infants who were exclusively or predominantly breastfed were receiving supplemental vitamin D.

Ensuring your baby gets enough vitamin D can seem challenging, regardless of whether you feed your child breast milk, infant formula or a combination. So what should you do? Here are a few simple ways to help ensure your baby gets enough vitamin D:

* If you breast feed, talk with your pediatrician to determine whether you should add a vitamin D supplement. While it is the gold standard for infant nutrition, breast milk by itself generally will not supply your baby with enough vitamin D to meet the AAP recommended levels.

* If you formula feed or partially formula feed your baby, you also should talk with your doctor. Standard infant formulas include 400 IU of vitamin D in 34 fluid ounces, but most babies consume an average of approximately 27 fluid ounces of formula a day over the course of their first three months of life. Look for a formula that supplies 400 IU in fewer fluid ounces, or talk with your doctor about supplements.

* Remember that your child’s need for vitamin D does not stop when he or she transitions to solid foods. Continue the conversation with your doctor and choose foods and drinks that contain vitamin D, including milk and milk-based beverages designed for toddlers.

“During infancy, you have just one chance to get nutrition right. For U.S. babies, vitamin D is often lacking but it is critical for healthy bones and body,” says Dr. Gregory Finn, a pediatrician at Blue Fish Pediatrics in St. Louis, Mo.

For more information on the importance of vitamin D and useful tips for including it in your child’s diet, visit www.healthychildren.org.