Vitamin D regulates calcium in a part of the intestine that previously was thought not to have played a key role. The findings have essential implications on how bowel disease, including ulcerative colitis and Crohn's disease, may disturb calcium regulation.
In a healthy person, the body consumes calcium to maintain strong bones and perform other vital functions like helping muscles move, and nerves carry information between the brain and body parts. Vitamin D is essential for this calcium absorption from the intestine and the function of the intestine.
The study, published in the journal Molecular and Cellular Biology, highlights the importance of the intestine's distal segments - including the colon - in vitamin D regulation of calcium and bone calcification. This regulation was previously thought to only occur in the proximal intestine, the first section of the intestine immediately beyond the stomach.
The study's lead author, Sylvia Christakos, says these findings suggest that vitamin D plays other roles as well. "The findings suggest that vitamin D have a role not only in calcium absorption but also in the cellular regulation of other necessary ions and in the function of intestinal stem cells," she said.
This research could lead to new strategies that can compensate for calcium malabsorption and improve intestinal calcium uptake efficacy to reduce bone loss due to bariatric surgery, small bowel resection, or reduced calcium absorption after menopause or due to aging.