Crohns disease (CD) is an autoimmune condition where part of the digestive tract becomes inflamed ulcerated and marked with sores. Along with ulcerative colitis Crohns disease is part of a group of diseases known as inflammatory bowel disease (IBD). 

Crohns disease may involve the immune system. The immune system of a person with CD may treat bacteria food or other substances as foreign invaders leading to chronic inflammation from the accumulation of white blood cells in the lining of the intestines and resulting in ulcerations and injury to the tissues. 

Data is emerging which shows that vitamin D supplementation may lengthen the remission in CD. A new study just published in this month's edition of United European Gastroenterology Journal suggests that vitamin D supplementation may impact the intestinal barrier dysfunction associated with Crohn's disease and play a role in the treatment of the condition.

The researchers assessed changes in gut barrier function and disease markers in CD in response to vitamin D supplementation. In this double-blind randomized placebo-controlled study 27 CD patients in remission were given 2000 IU/day of vitamin D or placebo for 3 months. They found that patients treated with vitamin D were more likely to maintain their intestinal barrier integrity whereas intestinal permeability increased in the placebo group. Increased intestinal permeability has been demonstrated to predict and precede clinical relapse in CD patients. In addition those with the highest blood levels of vitamin D showed signs of reduced inflammation measured by C-reactive protein and antimicrobial peptides.

A previous study had shown a clear chain of cellular events from the binding of DNA through a specific signaling pathway to the reduction of proteins known to trigger inflammation. The vitamin D receptor appears to bind directly to DNA and activate a gene known as MKP-1. MKP-1 interferes with the inflammatory cascade triggered by lipopolysaccharides (LPS) which includes a molecule known as p38 and results in higher levels of IL-6 and TNF-alpha. 

Autoimmune disorders occur when the bodies immune system is tricked into producing antibodies that attack its own tissues. Vitamin D helps autoimmune disorders by regulating T cells in the immune system. This makes the body more tolerant of itself and less likely to mount autoimmune responses.

Vitamin D deficiency has been linked to many autoimmune diseases including type 1 diabetes systemic lupus erythematosus multiple sclerosis and Crohns disease as research shows a higher prevalence of these diseases in those who are deficient in vitamin D. The severity of Crohns disease has been linked to the lowest vitamin D levels. 

There is plenty of evidence regarding the benefit of vitamin D supplementation for a multitude of health benefits besides autoimmune disorders. Given the fact that supplementation of vitamin D in its natural form is harmless and inexpensive many patients may benefit by having their vitamin D levels checked regularly and supplementing accordingly.