The role of calcium
40% of the weight of the human skeleton is composed of calcium.
99% of this calcium is stored in the bones and the teeth, the remaining 1% is found in the blood and tissues. That small percentage of calcium allows the blood to clot, allows muscles to contract and allows nerves to transmit messages to the brain (neurotransmission).
Calcium is an oligoelement whose primary function is bone mineralization. It can only be metabolized in conjunction with vitamin D and is transported and fixed to the bone through bone forming proteins that are activated by Vitamin K.
If the intake of either calcium, vitamin D or vitamin K is insufficient, calcium will slowly migrate from the bones leaving them fragile and porous.
People often believe that bones are like concrete and that once they are formed, they remain unchanged. This is not true. Our bones are living tissues continually renewing themselves.
When the amount of calcium in the blood decreases, the body draws from the calcium stocked in the bones to fill its needs. This is known as “re-absorption”. Once the calcium needs are met through nutrition, any surplus is returned to the bones. This is known as “formation”. If the intake of calcium, vitamin D or vitamin K is insufficient, calcium loss will continue and will eventually weaken the bones to the point of fracture.
Recommended Daily Allowance in calcium :
|Children 3 to 5 years||300 mg per day|
|Children 6 to 9 years||600 mg per day|
|Children and adolescents 10 to 20 years||800 to 1200 mg per day|
|Adults (men and women)||800 to 1200 mg per day|
|Pregnant and nursing women||1000 to 1200 mg per day|
|Menopausal women||1200 to 1500 mg per day|
|Men over 55||1000 to 1200 mg per day|
Foods rich in calcium are: all milk products (preferably skimmed), cereals, whole wheat bread, dry legumes (soybeans, lentils, beans, peas).