By Marc Sorenson, EdD, Sunlight Institute..
Inflammatory bowel diseases (IBD) include diseases such as Crohn’s disease and ulcerative colitis. Like multiple sclerosis, lupus and rheumatoid arthritis, they are autoimmune diseases that cause the immune system to attack its own tissue, in this case the tissues of the digestive system. This may cause extreme distress and damage.
Recent research shows that the IBD is associated with both sun exposure and vitamin D deficiency. In experimental IBD, vitamin D positively influences gut epithelial cells, innate immune cells, T cells, and the microscopic organisms that live in the gut. Separately from vitamin D, there is some scientific work that demonstrates that ultraviolet radiation (UVR), a component of sun exposure, can independently reduce IBD cells.
The authors of this research sum up their research with the following statement: “Together the data suggest that UVR suppression of T cells and potentially IBD are both vitamin D dependent and independent.”
Of course, we know that the natural way to obtain vitamin D is through sun exposure, so to me it appears that sun exposure, or sunlamp exposure, when available is the best method of suppressing the disease. Of course, proper nutrition is also imperative.
Many previous investigations have shown the remarkable positive influence of sun exposure on IBD. In a 12-year year investigation of hundreds of thousands of IBD patients, hospitalizations and prolonged hospitalizations were higher among those who had low sun exposure compared to those with very high sun exposure. The same relationship was shown between sun, bowel surgeries and deaths; more surgeries were needed for those patients who experienced the lowest sun exposure compared to those who had the highest sun exposure, and more deaths occurred among those with low exposure.
An interesting side note to this investigation was that a large number of non-IBD patients were also analyzed for sun exposure amounts. The same relationship existed as with the IBD patients; low sun exposure was associated with prolonged hospitalizations and more deaths when compared with high exposure. There is other research involving the association of Crohn’s disease to sun exposure, which, as above, found that surgery for the disease was significantly reduced among those patients who received more sun exposure.
It has also been shown that in the US, there is a north-south gradient for IBD,    meaning that the risk of developing IBD is significantly lower for the southern latitudes (where sun exposure is greater). So for a healthy gut, sun exposure plays a vital role. Be sure to get some sun exposure daily when available. That way, you will obtain your vitamin D, along with other photoproducts that may protect you from IBD as well as myriad other diseases.
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