EFFECT OF DIETARY CALCIUM IN ADULTS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 研究表明，细胞内钙（Ca）是人体脂肪代谢的调节因子。细胞内Ca增加导致脂肪储存增加和脂肪利用减少。调节脂肪细胞内Ca ~（2+）的方法可能成为预防和/或治疗肥胖症的新策略。维生素D的活性形式骨化三醇刺激细胞内Ca增加。通过抑制骨化三醇，细胞内Ca将减少，导致脂肪利用增加。引起骨化三醇抑制的一种机制是通过增加膳食Ca。通过增加血流中细胞外Ca的量，刺激甲状腺释放降钙素，降钙素是一种抑制骨化三醇的激素。膳食中的钙也会导致粪便中未吸收的脂肪排出。本研究将探讨补充钙和能量限制对减肥的影响。我们的目标是确定膳食钙与能量不足如何影响能量代谢和平衡，体重和组成，以及脂质代谢。 拟议研究的具体目标是： 1. 确定高钙饮食如何影响能量代谢和平衡。 2. 确定高钙饮食如何影响体重和成分。 3. 解释膳食钙如何影响脂质代谢。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. It has been shown that intracellular calcium (Ca) is a regulating factor in fat metabolism in humans. Increases in intracellular Ca cause an increase in fat storage and a decrease in fat utilization. Methods to regulate intracellular Ca in fat cells may be a new strategy in the prevention and/or treatment of obesity. The active form of vitamin D, calcitriol, stimulates an increase in intracellular Ca. By suppressing calcitriol, intracellular Ca will decrease causing an increase in fat utilization. One mechanism that causes the suppression of calcitriol is by increasing dietary Ca. By increasing the amount of extracellular Ca in the blood stream, the thyroid gland is stimulated to release calcitonin, which is a hormone that suppresses calcitriol. Dietary calcium could also cause excretion of unabsorbed fat in stool. This study will examine the effect of calcium supplementation and energy restriction on weight loss. Our goal is to determine how dietary calcium in combination with energy deficit affects energy metabolism and balance, body weight and composition, and lipid metabolism. The specific aims of the proposed research are: 1. To determine how high calcium diet affects energy metabolism and balance. 2. To determine how high calcium diet affects body weight and composition. 3. To explain how dietary calcium affects lipid metabolism.