Minerals are an important component of our diet. These are needed in small amounts but without them, we cannot have strong and healthy bodies. The body contains some 50 minerals, which serves specific functions in the body.
Some minerals are required in very small amounts i.e. less than 100mg and they are referred as micro minerals. E.g. iodine, zinc, manganese, copper, cobalt, and fluorine. Macro minerals are those, which are required in amounts more than 100mg/day. These include calcium, phosphorus, iron, sodium, potassium, & magnesium etc.
One very important mineral is calcium (Ca)
Almost 99% of our body’s calcium is found in the hard tissues of the body i.e. the bones and teeth. The rest is distributed in blood and soft tissues.
Most of the bone formation in the fetus occurs in the 8TH & 9TH month of the pregnancy. At birth, the bones are very soft. Throughout the growth phases, the bone elongates, thickens, & hardens.
The first teeth are formed from 4TH -6TH week of pregnancy. By the 12TH week, these teeth calcify. These are the milk teeth. The permanent teeth are formed by the child’s 3RD birthday. So for proper growth of the body, optimum amount of calcium intake is necessary.
The requirement of calcium from childhood to adults ranges from 400-600mg/day. The important functions of calcium include:
- It is involved in the formation of bones & teeth.
- Calcium helps in muscle contraction.
- It is essential in controlling transmission of nerve impulses
- It is involved in the absorption of vitamin b12, in the action of fat digesting enzyme (pancreatic lipase) and in the secretion of insulin from the pancreas.
- Calcium is also needed for normal clotting of blood, as it is required for the conversion of protein prothrombin to an enzyme thrombin that converts a soluble blood protein fibrinogen into fibrin (blood clot).
So calcium not only gives strength to our basic structure but also is required in smaller amounts for the proper functioning of every cell in the body. All the nutrients that we take in our body through our diet are only of importance if they are absorbed and utilized in the body aptly.
Most of the utilization of calcium occurs in the small intestine as calcium salts are most soluble in acidic medium. On an average 30-40% of the dietary calcium is absorbed in adults. Growing children, pregnant & lactating women absorb 50-60% of dietary calcium. As their bodies are in a state of growth & development the efficiency of calcium, utilization also increases.
The efficiency of calcium absorption decreases to 20-30% after 45 years of age in women & 60 years in men. Estrogen increases calcium absorption and so after menopause calcium absorption decreases. In elderly, it is only about 10%. There are certain factors, which favors the absorption of calcium in the body while some other factors inhibit the same.
The factors, which favor calcium absorption, include:
- Vitamin D: which is available naturally from sunlight( up to 9:00 am)
- Acidic medium: from citrus fruits like lemon.
- Lactose: which is present in curd?
When calcium intakes are low, the body adapts, by absorbing a greater proportion of the dietary calcium available and excreting less.
The factors, which inhibit the absorption of calcium, are:
- Oxalic acid: mostly present in spinach, forms an insoluble complex with calcium which cannot be absorbed.
- Phytic acid: present in outer most layer of whole grain cereals
- Excess fat in diet.
- Lack of exercise.
- Increased fiber intake.
- Emotional instability in situations of stress, tension, anxiety, grief, and boredom.
- Aging.
- Caffeine.
- Drugs.
Deficiency
Deficiency of calcium manifests due to insufficient intake. When sufficient calcium is not supplied, pregnant women lose calcium from their body tissue to fulfill the needs of the growing fetus Similarly, nursing mothers lose calcium from the formation of milk. This can further lead to weak & fragile bones; more prone to fractures (osteoporosis).
In children, lack of calcium affects their growth. The skeletal system doesn’t mineralize properly resulting in weak bones, which are unable to support the weight of the body. In children, this can lead to rickets, which is characterized, by bowed legs, enlarged joints & other deformities. The teeth are also affected in calcium deficiency and the mechanism of blood clotting is also disturbed.
Sources
It is found in both animal and plant foods. Richest sources include milk & milk products & green leafy vegetables. Cereals like ragi are also a good source.
Foods like crab, sesame seeds; skimmed milk powder contains more than 1000mg of calcium in a serving of 100g. Cheese contains 950mg/100g.
Therefore, a diet rich in calcium can lead to a strong & healthy body with proper functioning of its systems. For growing kids it is more important to ensure proper growth & development. Having two glasses of milk. Including curd & cottage cheese in diet can very well meet the daily requirement of calcium.
In addition, do not forget to have a good amount of sunlight along with it. So enjoy a calcium rich diet and have a strong & healthy body!
