Supplementing with vitamin D early in life may reduce the chances of developing type 1 diabetes later on, according to a new study published in the Archives of Disease in Childhood.

Recent research has shown that vitamin D, well known for its important role in bone health, may be essential for many other aspects of health as well, including heart health and the prevention of chronic diseases such as cancer and multiple sclerosis. To determine the impact of early vitamin D supplementation on the development of type 1 diabetes, the authors reviewed five studies, which included 6,455 people who were followed from the time of supplementation to an average age of 15 years, and some for as long as 30 years.

A strong association

Type 1 diabetes risk was significantly reduced in babies who were given vitamin D compared with those who did not receive supplementation. Among those who were given vitamin D, those who received higher amounts were at even lower risk than children taking lower amounts. The authors noted that timing of supplementation may also be important, as children who received vitamin D between 7 to 12 months of age had a lower risk of developing type 1 diabetes compared with children who received it between 0 and 6 months. Children who received regular as opposed to irregular supplementation had a further reduced risk.

Types and dosages of supplementation varied among the reviewed studies. One study used cod liver oil from one to more than five times per week, and another study recommended regular supplementation with 2,000 IU of vitamin D per day.

“The results of the study suggest that vitamin D supplementation in infancy may offer protection against the development of type 1 diabetes,” said Christos Zipitis and his colleague from the Department of Pediatrics at Manchester Children’s University Hospitals, Manchester, United Kingdom. They found that children given vitamin D had a 29% reduced risk of developing type 1 diabetes compared with those who were not given supplements.

Good for the immune system

Type 1 diabetes is a serious condition caused by the destruction of cells in the pancreas that secrete insulin. When these cells are destroyed, the body lacks insulin and blood sugar levels rise. Because high blood sugar can lead to many serious health conditions, people with type 1 diabetes must take insulin in order to lower their blood sugar. The destruction of pancreatic tissue that leads to type 1 diabetes is thought to be due to a dysfunctional immune system. Vitamin D may help prevent type 1 diabetes by keeping the immune system healthy, although the exact mechanism by which the vitamin may be protective is not known.

Vitamin D may be obtained through sun exposure, diet, and supplementation. Dietary sources include fish, cod liver oil, and fortified milk. Check with your child’s pediatrician to find out the latest recommendations regarding vitamin D and the health of your child.

Jane Hart, MD