Intestinal calcium absorption more than doubles during pregnancy, whereas the maternal skeleton is resorbed to provide most of the calcium content of breast milk during lactation.
Intestinal calcium absorption is dependent on serum vitamin D concentration.
Intestinal calcium absorption is increased after feeding a low calcium diet or under conditions of increased calcium needs, such as during growth, via a parathyroid hormone (PTH -vitamin D mediated PTH -vitamin.
Intestinal calcium absorption was determined by fecal recovery of Ca. Stool weight and mineral content were assessed during 3 days, and 24-h urinary mineral content and serum chemistry were assessed over 5 days at the end of each phase.
Cortisol also inhibits intestinal calcium absorption, which in turn causes increases in PTH production and the rate of bone resorption.
A form of vitamin D called calcitrial increases the efficiency of intestinal calcium absorption and also interacts directly with osteoblasts to increase osteoblast function.
Mineralization defects are due to the decrease in the efficiency of intestinal calcium absorption, which results in a decrease in ionized calcium concentrations in blood.
This study reports the intestinal calcium absorption of a new product that combines calcium and other nutrients from milk and the consumer's desire for soft drinks.
Black individuals have lower urinary excretion and increased intestinal calcium absorption, reduced levels of 25(OH D, and high levels of 1.25(OH)2D and parathyroid hormone (PTH).
It is not until the postnatal period, when intestinal calcium absorption becomes an active process, that the organism begins to depend upon vitamin D/calcitriol.
At times of increased need, such as during pregnancy, lactation, and adolescent growth, circulating levels of calcitrial are increased, resulting in an increase of up to 80 percent in the efficiency of intestinal calcium absorption.
