A randomized , double-blind , placebo-controlled , clinical trial was designed to determine whether calcium supplementation will reduce the colorectal epithelial cell proliferation rate and normalize the distribution of proliferating cells within colorectal crypts ( i.e. , shift the zone of proliferation from the entire crypt to the lower 60 % of the crypt , which is thought to be the normal proliferative zone of the crypt ) in patients with sporadic adenomas .
