Calcium is an important mineral which is a part of bones, teeth and soft tissues and is essential for the functioning of the muscles and nerves, as well as the secretion of hormones and enzymes.
The role of calcium in the body
Calcium builds bones and teeth. It is necessary for the transmission of nerve impulses, muscle contraction, activation of the enzyme. Participates in the structure of hormones and blood clotting. The biological role of calcium is not fully revealed. It was found that it could reverse the change in mood and pain before and during menstruation and other symptoms of PMS. Foods rich in calcium reduce the risk of colon cancer and lower the blood pressure. It is used for osteoporosis, osteopenia, hypocalcemia, tetany, hypoparathyroidism and rickets.
The amount of calcium in the blood is constant. If the organism does not receive enough calcium from the food then it uses the calcium from the bones, thus they become brittle and prone to fracture. The level of calcium in the bones depends from the quantity of food and physical activity. If a man is physically active then the incorporation of calcium in the bones is increased, while the inactive have a larger loss. Calcium is gradually incorporated into the bones and strong bones are created from childhood. After thirty years of age the density is reduced more rapidly in women after menopause.
Daily needs of calcium:
For the normal growth of the children around 800mg of calcium a day is necessary, adolescents for the formation of strong bones need about 1200mg, women of child bearing age 800mg, 1000mg for men. Daily needs of pregnant and lactating women are 1200mg. Baby's receive enough calcium from the mothers milk. However, if the mother does not bring food in sufficient quantity for the baby's needs then is taken from her body. In postmenopausal women due to estrogen deficiency the loss of calcium is increased so that their needs are 1500mg. In the older ages the loss of calcium is increased so in this age we should ensure adequate intake.
Sources of calcium
Calcium is found in milk, yogurt, cheese and other dairy products. Interestingly, it is found more in dairy products with a lower percentage of fat. There is a large amount of calcium in the canned fish with bones.
At many people the milk interferes with welding and allergies. Fortunately, there are other calcium rich foods such as green beans( more yellow than green), beans(more white than yellow), dried figs , tofu, cabbage, cauliflower, broccoli, pumpkin, chick pea, soya bean, lentil, black onion, celery, peanuts, walnuts, sunflower seeds and in some juices, soy milk, and other industrial products are enriched with calcium.
Source: The begginer's guide to healthy eating Andrew Weil