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Osteoporosis: The Role of Calcium in Maintaining Bone Strength

and the role of calcium in preventing osteoporosis

Calcium is needed to maintain healthy bones.

The bones of the human skeleton contain 99.5% of the total calcium in the body. The calcium within bones is available to the body should the body need it for other purposes. It is the activity of bone osteoclasts which absorb the calcium in the bone and release it into the blood stream (more about this on our parathyroid and osteoporosis page). Remember, it is the calcium within the bones which makes them strong.

The daily recommended dietary calcium intake varies by age, sex, and menopausal status. Recent studies have shown that many American girls do not get enough calcium in their diet after the age of 11. Much of this is blamed upon the substitution of sodas in the diet for milk, yet the problem does not seem to be the same for males (for a number of subtle reasons).  It is important to know that many women of all ages in the US do not get enough calcium in their diet either.  The vast majority of endocrinologists encourage their female patients to take supplemental calcium daily.  One of the easiest and most effective methods of increasing your calcium intake is to take an oral calcium supplement daily.  There are several forms of oral calcium readily available over the counter (without a perscription) such as Citracal which can help maintain healthy bones and prevent osteoporosis.  The following list shows the recommended calcium intake according to age, sex and hormone status.


Age Amount of Daily Calcium
Birth to 6 months 400mg
Six months to 1 year 600mg
Children/Young Adults  
One to 10 years 800 - 1,200 mg
11 to 24 years 1,200 - 1,500 mg
Adult Women  
Pregnant or Lactating 1,200 - 1,500 mg
25 to 49 years (premenopausal) 1,000 mg
50 to 64 years (postmenopausal taking estrogen or similar hormone) 1,000 mg
50 to 64 years (postmenopausal not taking
estrogen or similar hormone)
1,500 mg
Over 65 years old 1,500 mg
Adult Men  
25 to 64 years old 1,000 mg
Over 65 years old 1,500 mg

Source: National Institutes of Health Consensus Panel, Optimal Calcium Intake, 1994.