Influence of intestinal resection and type of diet on digestive utilization and metabolism of magnesium in rats.

The influence of intestinal resection and type of diet on nutritive utilization of magnesium was studied in rats in which 50% of the distal small intestine was removed and in sham-operated controls. Nutritive parameters were analyzed after feeding the rats different diets for one or three months after surgery. Loss of 50% of the distal small intestine reduced digestive utilization of Mg as reflected in the mineral content of bone, however digestive and metabolic utilization of Mg were seen to recover by three months postsurgery. When dietary fat was supplied as equal parts of medium chain triglycerides, sunflower seed oil and olive oil instead of 100% olive oil, Mg absorption and retention were enhanced in resected rats after one month with the beneficial effects on Mg metabolism becoming even more marked after three months. One month after resection, dietary supplementation with vitamin D3 clearly stimulated digestive utilization of Mg. Although this effect was less notable at three months, nutritive utilization of Mg remained higher than in resected rats fed a diet lacking vitamin D3 supplementation. Dietary levels of vitamin D3 favored the deposition of Mg in bone tissue.