Blood calcium balance

calcium balance:

The normal level of calcium is 8.5-11 micro/ml

If the calcium level is reduced to less than 8.5 micro/ml the hormone called parathyroid hormone is produced that affects two main traget tissues: 1- bone: increase the bone resorption releasing calcium from bone the blood 

2- kidney: increase the absorption of the calcium from distal tubule of the kidney also in kidney it helps in activation of inactive vitamine D to active form which increase the absorption of calcium from intestine.

But if there was increasing in the level of calcium more than 11 the hormone called calcitonin will be produced which affects three target tissues: 1- bone: decrease the bone resorption so decrease clacium releasing from the bones.

2- kidney: prevent absorption of the calcium form the distal tubule of the kidney.

3- Intestine: prevent absorption of calcium form food in intestine.

note: persons with osteoporosis take drugs that contain calcitonin to prevent more bone damage by preventing bone resorption.

another advice is : if you are takning calcium supplement you should also take Vitamine D supplement beacause calcium can not be absorbed or used without Vitamine D.