“Vitamin D for Inflammatory Bowel Disease” Inflammatory bowel disease is a chronic
inflammatory condition of the intestine that includes Crohn’s disease
and ulcerative colitis. If you compare identical twins, even
though they have the same genes, most of the time if one twin
has it, the other does not. So there must be some important
nongenetic trigger factors. What might they be?
Well, studies like these offered a clue. Why do those living in the southern
United States have lower IBD rates than those living in the north? Maybe it’s because those living
in the south get more sun, which means more vitamin D,
which may mean less inflammation. So do those with Crohn’s and
ulcerative colitis with low vitamin D levels have worse disease?
Apparently so. Increased risk of surgery
and hospitalization. And those that normalized
their vitamin D levels appeared to reduce
their risk of relapse. But instead of better vitamin D
leading to better Crohn’s, maybe the better Crohn’s
led to better D. They felt so good they
went outside more. You can’t tell if it’s cause and effect
unless you put it to the test. The first pilot study tried
a thousand units of vitamin D a day and saw no change in the
Crohn’s disease activity index, though at 6 weeks there may
have been a slight increase in inflammatory bowel disease
quality of life scores. But even that disappeared by year’s end.
Pretty disappointing results. Maybe they didn’t use enough.
How about 1200 a day? The relapse rate appeared
to be cut in half, though there were too few people in the
study to reach statistical significance. How about 2,000 international
units of vitamin D a day? Gut leakiness, so called
intestinal permeability, continued to worsen in the placebo
group, but appeared to stabilize in the Vitamin D group, though only
those who reached blood levels over 75 nanomoles per liter appeared to
have a significant drop in inflammation. And indeed, if you start Crohn’s patients
on a thousand and then ramp it up until they reach a target blood level,
you can get a significant boost in quality of life, accompanying a
significant drop in disease activity. Disease scores under 150
are considered remission, so the majority of patients
achieved remission, with improvements in disease
activity in all but one patient. This suggests that Crohn’s
patients may want to take 5,000 international units
of vitamin D a day. But that’s nearly 10 times the RDA.
Why so much? Because that’s what it may take
to get normal vitamin D levels, as in normal-for-our-species levels,
the kind of levels one might get running around half naked in Africa,
as we did for millions of years.