There are more than 200 bones in the human body. The main function of the skeleton is to add structure to the body, protect organs, and enable the body, with the help of the attached muscles, to move.

Bones also play a role in several other bodily functions.

The formation of blood cells takes place in the marrow within certain bones. Bones also act as a storehouse for minerals, especially phosphorus and calcium. About 98 percent of the body’s calcium is stored in its bones. Every cell in the body requires small amounts of calcium to function properly.

When blood calcium levels fall, bones then release calcium that has been stored. The body uses intricate mechanisms to keep calcium levels balanced. When blood levels of calcium are low, the parathyroid glands secrete parathormone. This activates bone cells called osteoclastsins in order to break down bone to release the calcium that is needed by the body. This also triggers other hormones that counteract mineral loss in these bones to keep them strong during this process.

When blood calcium levels get too high, the thyroid gland secretes the hormone calcitonin, which blocks the actions of parathormone.

There are several factors that affect both calcium absorption and loss. These include, gender, weight, ethnic background, heredity, disease factors, and activity levels.

There are two areas of strengthening bone we’ll explore. These are diet and exercise. When using a calcium supplement, to complement your diet, it’s not just important how much you take, but how you take it. I recommend healthy folks take between 1,200-1,500 mg of calcium a day.

The two main forms of calcium readily available are calcium carbonate and calcium citrate. Both are well absorbed, but should be taken differently. Calcium carbonate needs to be taken with food for proper absorption, whereas calcium citrate needs to be taken on an empty stomach. Be sure to take one or the other, not both.

Your total calcium allowance per day should be divided and taken at two different times. Also, do not take your calcium within an hour of taking vitamin C. Calcium is a base and vitamin C is acidic. If they are both in the stomach at the same time, they will cancel each other out.

When it comes to calcium fortified orange juices, the form of calcium used is calcium hydroxide, which is not affected as much by the vitamin C in the juice. You also, need vitamin D and magnesium for calcium absorption, so I recommend a well-balanced vitamin/mineral supplement (we’ll talk more about that later).

Proper exercise is also crucial for bone strength and health. Weight training is excellent for this. Skeletal muscles have something called an origin and an insertion. The origin point of the muscle is attached to the immovable bone. The insertion point of the muscle is attached on the other end to the movable bone. When you lift weights properly, the bones between the origin and insertion are stressed. The brain senses this and signals the body to send calcium to harden these bones.

With proper strategy you can make real progress at any age, but make sure you get instruction from someone who is knowledgeable and experienced. Get your doctor, trainer, and nutritionist involved. Take care of your bones and they’ll really support you.

Diet or exercise question? Email me at dwcrocker77@gmail.com. David Crocker of Landrum has been a nutritionist and master personal trainer for 29 years. He served as strength director of the Spartanburg Y.M.C.A., head strength coach for the USC Upstate baseball team, the SC state champion girls gymnastic team, and the Converse College equestrian team. He served as a water safety instructor to the United States Marine Corps, lead trainer to L.H. Fields modeling agency, and taught for four semesters at USC Union. David was also a regular guest of the Pam Stone radio show.