FNN 100 Lecture Notes - Lecture 11: Osteoporosis, Dental Caries, Skeletal Fluorosis

• School: Ryerson University
• Department: Nutrition and Food
• Course: FNN 100
• Professor: Barbara Wendland

Document Summary

P makes up about one percent of adult body weigt. 85% is found in bone and teeth, remainder is in soft tissues. The p in tissues is part of molecules with both structural roles and regulatory roles. Mechanisms: mostly passive diffusion, some active transport facilitated by vit d. Controlled by: vit d and p transporters. P and ca form the hydroxyapatite crystals. Blood levels not as strictly controlled as ca but maintained in conjunction with ca for adequate bone mineralization. When blood levels are low, triggers active form of vit d increases absorption of both p and ca and resorption from bone. High intake increases urine loss- (cid:449)o(cid:374)(cid:859)t affe(cid:272)t (cid:271)lood le(cid:448)els too (cid:373)u(cid:272)h. At times when pth is not secreted (i. e when?) P iks retained by the kidney and ca is excreted. Ca and p react in opposite ways as blood ca levels rise, p levels fall.