Calcium--osteoporosis and blood pressure.

Calcium is the main essential mineral for building strong bones and sound teeth. Bone remodeling occurs throughout life; new bone is deposited and existing bone is replaced. Peak bone mass development is obtained up to 35 yr of age after which bone resorption is increased. It is therefore imperative that Ca intake meet the recommended dietary allowances not only during the growing period but throughout life. Milk and dairy products are the major food source of Ca in the US diet, supplying about 61% of our intake while other food groups supply the rest. It is almost impossible to supply the recommended dietary allowances of Ca without consuming milk in some form, as most other food groups are low in Ca content. The Ca in dairy products is bioavailable and readily absorbed by the body whereas Ca in other food sources may be less so. Several government surveys have shown that a large proportion of the US population, especially females 11 yr of age and older, have very low Ca intakes that do not meet the recommended dietary allowances for Ca. Recent developments in osteoporosis (porous, brittle, and fragile bones) have indicated that low Ca intake or bioavailability of this mineral is one of the major factors involved in this crippling bone disease. Osteoporosis affects 15 to 20 million middle-aged and elderly persons, especially postmenopausal women who are susceptible to bone fractures. Recent studies on nutrient intake and high blood pressure have reported an inverse relationship between dietary Ca intake and blood pressure levels.(ABSTRACT TRUNCATED AT 250 WORDS)