The role of the intestine in bone homeostasis.

The intestine is critical for calcium absorption and skeletal mineralization. Nutritional factors affect the dietary intake of calcium and its bioavailability in the intestine. Individuals differ considerably in their ability to absorb calcium but the reasons for this physiological variation are not fully understood although much is now known about the effects of vitamin D metabolites and the molecular steps in calcium absorption. Bone changes are found in many intestinal disorders including lactose intolerance, coeliac disease, short bowel syndrome, small intestinal bacterial overgrowth and Crohn's disease.