Infants, children and adolescents should get double the recommended amount of vitamin D because of evidence that it may help prevent serious diseases, the American Academy of Pediatrics said.

Many infants appear to lack vitamin D, which doesn’t necessarily show immediate symptoms but can lead to a weakened immune system that is more predisposed to disease. Many previous studies indicate that vitamin D deficiency plays a significant role in causing seventeen varieties of cancer as well as heart disease, stroke, hypertension, autoimmune diseases, diabetes, depression, chronic pain, osteoarthritis, osteoporosis, muscle weakness, muscle wasting, birth defects and periodontal disease.

According to a study made on 380 children aged from 8 to 24 months and released earlier this year by researchers from Children’s Hospital Boston, 40 percent had less-than-optimal blood levels of vitamin D. Moreover, 12 percent actually had vitamin D deficiency. About a third of these kids had bone demineralization, a sign of thinner bones when being X-rayed. Breastfed babies were more likely to have low levels of vitamin D as breast milk is the perfect food except it lacks vitamin D, Dr. Catherine Gordon, lead author if the study, said at the time.

The new guidelines say children, from newborns to teens, should get 400 units daily of vitamin D, meaning double the amount recommended in 2003. To meet this recommendation, millions of children will need to take daily vitamin D supplements, the AAP said. However, children on formula may not need the supplements as baby formula contains vitamin D. But breast-fed babies need the daily supplements as well as the other kids and teenagers because, although most commercially available milk is fortified with vitamin D, they don’t drink enough of it. “Enough” is defined as four cups a day, Dr Frank Greer, the reports’ co-author, said.

“We see lots of long-latency diseases linked with vitamin D deficiency. There's interplay between vitamin D and the immune system,” said Dr. Carol Wagner, a pediatrician at the Medical University of South Carolina and a member of the American Academy of Pediatrics Section on Breast-feeding Executive Committee. She was also a co-author of the report.

Besides fortified milk, vitamin D is found in many dietary sources as fortified breakfast cereals, fortified orange juice, fish, eggs, and cod liver oil. The sun also contributes significantly to the daily production of vitamin D, and as little as 10 minutes of exposure is thought to be enough to prevent deficiencies. This is the reason why the vitamin is also called the “sunshine vitamin.” However, the AAP recommends supplements rather than sunbathing because of the sun’s link to skin cancer.

The new recommendations will be made public Monday at an academy conference in Boston. They are to be published in the November issue of the academy’s journal, Pediatrics under the title “Prevention of Rickets and Vitamin D Deficiency in Infants, Children and Adolescent.”