This
study (1) looks at the association between added sugar consumption of less than
and greater than 50 g per day and smoking relative to CD. The study consists of a repeat or secondary
questionnaire sent to 104 CD patients and 153 controls 24 months after an
initial study. The initial study, the
author says, found strong associations between refined sugar intake and CD and
between smoking and CD. Ultimately, no
further association between CD and sugar intake was found in the smoker
population, and a conclusion was drawn that the lack of a compounding influence
could suggest that increased sugar intake and smoking work through a common
mechanism to bring about CD.
While the above conclusion is concurrent with data, an
important piece of information is omitted:
results also showed that there was an additional correlation amongst smokers
as well, such that whether they be control or patients with CD, the no sugar
added category also was found to equate.
In reading the abstract, one might be misled into believing that the correlation
amongst smokers with increased sugar intake whether or not diagnosed with Crohn’s
is the only one. Because the
correlation also exists with no sugar added, one might conclude, alternately,
that added sugar does not provide a risk for Crohn’s, since smoking without
added sugar is a sufficient risk factor to provide comparable results. Ultimately, smoking, without added sugar or
with over 50g of sugar added is found to result in comparable risk for Crohn’s. Amongst non-smokers, both the no added sugar
and the low added sugar groups showed comparable risk.
Sample size and patient matching to age (within two
years) and sex to two controls is a significant coup and not widely
accomplished in human studies. Future
direction for this study will include, as many references indicated, looking at
newly-diagnosed cases rather than two-year old cases for better determination
of study results.
1. Katschinski, B., et al. "Smoking and sugar intake are
separate but interactive risk factors in Crohn's disease." Gut 29.9
(1988): 1202-1206.
I'm glad you commented on the fact how there was not a direct correlation between those adding sugar to their coffee to smokers with or without Crohn's disease because it is true. Even when I was class I had forgotten we had mentioned that until I had read your post again.
ReplyDeleteI wonder what the physiological mechanism behind these results is. Why is it that the intake of added sugar does not correlate with the incidence of CD in smokers?
ReplyDeleteI'm thinking that smoking is correlated with the incidence of CD, and that the potential added sugar does not further influence a smoker's chance of getting CD. The results tell us that the intake of added sugar in non-smokers is correlated with the incidence of CD, so maybe this guess has some validity to it. However, I would be interested in seeing the actual mechanism that takes place.