Colon Cancer: A Disease of Fibre Depletion or of Dietary Excess ?

Abstract

It cannot be denied that the fibre theory is attractive and appears to be firmly based in ‘common sense’ – one would expect a priori that all of the statements are likely to be true. When further investigated, however, we find that ‘common sense’ has again let us down and that an expected relation is in fact reversed simply because the situation is much more complex than expected (the best example is the lack of relation between bowel transit time and the degree of bacterial degradation of fecal steroids, etc.). There is little virtue in criticising a hypothesis unless a better one can be suggested as a replacement. I would therefore like to reiterate the hypothesis that I and my colleagues have been investigating. We believe that it offers a better rationalisation of the facts.

Daily Elimination of Fecal Neutral Sterols by Humans

“…This is indeed the case for subject F (tables 11, HI) and also for subjects T. Additional daily analyses with these latter show that the proportion of coprostanol does not vary more than 4%, whereas the masses of sterols eliminated can have a ratio of 1:10 (as for subject T2 in figure 2). Moreover, analogous findings have been reported by other authors (9).…”

Farnesoid X Receptor Deficiency in Mice Leads to Increased Intestinal Epithelial Cell Proliferation and Tumor Development

“…Consumption of high-fat diet and increased fecal excretion of bile acids is associated with elevated incidence of colon cancer (Hill, 1974;Stamp, 2002). However, the mechanism by which bile acids contribute to colorectal cancer is not clear.…”

Intestinal Disease and the Urban Environment

“…Blood cholesterol levels in cancer patients, however, tend to be low rather than high (52) (55). Some species of clostridia have been reported to be of excessive frequency in patients with colon-cancer (55,56), but this finding has not been confirmed in subsequent studies (57,58 (59). In rats monocontaminated with bacteria having ,3-D-glucosidase activity and in conventional rats, cycasin given orally is carcinogenic and produces carcinoma of the large intestine.…”