Vitamin D has long been known for its role in calcium absorption and maintaining bone health. In recent years, studies suggest vitamin D’s possible role in infections, diabetes, cancer, multiple sclerosis and autoimmune and cardiovascular diseases.

Rajni Ahlawat

Very few natural foods contain vitamin D; the flesh of fatty fish and fish liver oil are among the best resources. Small amounts of vitamin D are found in beef liver, cheese and egg yolks. Fortified foods such as milk, orange juice, yogurt, margarine and cereal, provide most of the vitamin D in American diet. The recommended daily amount of vitamin D is 400 international units (IU) for children up to 12 months, 600 IU for ages 1 to 70 years, and 800 IU for people older than 70.

Vitamin D deficiency is common in children with gastrointestinal health conditions such as celiac disease (CD) and inflammatory bowel diseases (IBD), including Crohn’s disease or ulcerative colitis. Current research has suggested that patients with untreated celiac disease are at increased risk for developing low bone mineral density (BMD), osteoporosis and bone fractures.

In an article about vitamin D in pediatric gastrointestinal disease published in the journal “Current Opinion in Pediatrics,” I wrote that vitamin D deficiency is common in children with celiac disease and inflammatory bowel diseases. Normal vitamin D levels are considered more than or equal to 30 ng/ml. If vitamin D levels are between 20 to 30 ng/ml it is called vitamin D insufficiency and if less than 20 ng/ml it is vitamin D deficiency.

Vitamin D levels should be checked in children with celiac disease and inflammatory bowel diseases when initially diagnosed. If levels are found low, children should be given vitamin D supplements and the levels should be followed to check if they normalize. Cholecalciferol or vitamin D3 is the preferred form of vitamin D supplementation, however, there is no consensus on the vitamin D treatment dosing regimen.

In another study, I assessed vitamin D levels in newly diagnosed children with celiac disease and compared them to children with functional gastrointestinal disorders. I found that vitamin D levels were insufficient in both the study groups. Vitamin D levels were strongly associated with dietary intake of vitamin D, such as milk and supplements. Since children with celiac disease had low vitamin D levels at the time of diagnosis, it is recommended to assess vitamin D levels in these children.

Both of the above studies show that it is very important to diagnose and treat vitamin D deficiency in children with gastrointestinal disease, especially celiac disease and inflammatory bowel diseases. Consult your primary care provider about making sure your child is getting the proper amount of vitamin D.

Dr. Rajni Ahlawat, pediatric gastroenterologist at Marshfield Clinic Health System, is an expert in treating pediatric gastrointestinal diseases and is involved with multiple ongoing research projects involving vitamin D deficiency in gastrointestinal disorders.