Crohns disease is an inflammatory disease of the intestines that may affect any part of the gastrointestinal tract from anus to mouth, causing a wide variety of symptoms. It primarily causes abdominal pain, diarrhoea (which may be bloody), vomiting, or weight loss, but may also cause complications outside of the gastrointestinal tract such as skin rashes, arthritis and inflammation of the eye.
A new study has found that Vitamin D, readily available in supplements or cod liver oil, can counter the effects of Crohn’s disease.
The data collated in this study suggests, for the first time, that Vitamin D deficiency can contribute to Crohn’s disease. Epidemiologically it had already been noted that people from northern countries, which receive less sunlight, necessary for the fabrication of Vitamin D by the human body, are particularly vulnerable to Crohn’s disease.
Crohn’s has been described as an autoimmune disease in which there exists and inappropriate reaction via the innate immune system to the commensal flora. It is surmised that a defect in the innate immune handling of intestinal bacteria leads to an inflammatory response that may lead to an autoimmune condition.
This study revealed that Vitamin D acts directly on 2 key genes related to Croh’s called the beta defensin 2 gene, which encodes an antimicrobial peptide, and the NOD2 gene that alerts cells to the presence of invading microbes. If NOD2 is deficient or defective, it cannot combat invaders in the intestinal tract.
Clinically this represents a simple and safe method of limiting risk in siblings of patients with Crohn’s disease that haven’t yet developed the disease. It is a proportional recommendation to ensure they are vitamin D sufficient. It’s something that’s easy to do, because they can simply buy Vitamin D supplements. The vast majority of people with Crohn’s in the family would be candidates for Vitamin D treatment.
The dosing would ideally be tailored to appropriate blood tests, but a dose of 2000iu per day during the winter months or when there is inadequate sunlight exposure would be safe.
A further report in the BMJ looked at a long term study with over 500,000 people called EPIC. This study added weight to the requirement for levels of Circulating vitamin D concentration (25-hydroxy-vitamin-D, 25-(OH)D) to be above 50nmol/l as below this level risk for colorectal cancer increased and above 75nmol/l risk declined. They concluded:
The results of this large observational study indicate a strong inverse association between levels of pre-diagnostic 25-(OH)D concentration and risk of colorectal cancer in western European populations.
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