Table 1.

Summary of studies on calcium and colon cancer

·Majority of epidemiologic studies suggest protective effect

·In vitro studies: decreased proliferation and increased differentiation and maturation of many types of epithelial cells

·In vivo rodent studies: numerous studies demonstrated inhibition of colonic tumor development preceded by decreased hyperproliferation, ODC and ras mutations, binding of bile and fatty acids into insoluble complexes reducing irritant and hyperproliferative effects, reduced cytotoxicity of fecal water

·Human studies: decreased hyperproliferation in most studies, increased differentiation and maturation of colonic epithelial cells, binding of bile and fatty acids into insoluble complexes, decreased cytotoxicity of fecal water

·Decreased recurrence of human adenomas