CHEM 181 Lecture Notes - Lecture 8: Bone Resorption, Hip Fracture, Bone Density

• School: McGill University
• Department: Chemistry
• Course: CHEM 181
• Professor: David Harpp

Document Summary

Calcium: main sources: cheese, milk, yogurt and broccoli, have about 1kg in body --99% bones and teeth; 1% neural transmission and blood clotting, discovered 1883 by ringer that calcium needed for nerve impulses to function. Intake: varies enormously, and dependent on age: 700mg/day 0-3 years old, 1000 mg/day 3-10 years old, 1300 mg/day 10-20 years old, 1000 mg/day 20+ years old. Calcium requirement: much lower for women than men, probably bc many women are osteoporotic, extreme level athletes have higher recommendation for calcium intake since eat more calories from food (1. 2-2. 7x daily allowance, women-men) If intake 250mg/day, 85mg/day found in urine, and 265 in stool --balance of - If intake 820 mg/day, 180 mg found in urine, 610 in stool and so --balance +30mg: just about break even. If intake 1,250mg then get +100mg balance, and intake 2,350 get +160mg balance.