Children harangued by their parents to drink milk for strong hones and teeth now have more reasons to drain their glasses. In a flurry of research published over the past six months, calcium is turning out to have important health benefits throughout the body, from lowering blood pressure to warding off premenstrual syndrome (PMS) and cancer. 
For many years, scientists have known that calcium - the body's most abundant mineral - contributes to many physiological processes, including muscle contraction, nerve transmission, blood clotting, hormone secretion and the production of digestive enzymes. 
Among recent studies supporting the health benefits of consuming more calcium, some of the most compelling relate to the mineral's effect on blood pressure. A study published last full in the American Journal of Clinical Nutrition found that adding calcium to the diet of 116 African-American teenagers (who ordinarily ingested little calcium) lowered the adolescents' blood pressure. African-Americans are more than twice as likely to develop high blood pressure - accompanied by heightened risk of cardiovascular disease - as their Caucasian counterparts. 
The calcium - cancer connection is more circumstantial. Before colon cancer fully develops, epithelial cells lining the colon begin to grow abnormally, providing physicians with a sign that patients may be at increased risk. In research published in September 1998 in the Journal of the American Medical Association, scientists reported that when subjects doubled their consumption of low-fat, calcium-rich dairy products, abnormal epithelial cell growth in the colon reverted to normal patterns. 
Such findings come at a time when Americans, particularly children, are getting less calcium than they did in the past. Nutritionists agree that diet is nearly always a better source of calcium than are supplements. Foods like milk include additional nutrients, such as vitamin D, that help the body fully benefit from the nutrient. Yet non-milk drinkers need not despair: A variety of foods, from cheese and yogurt to sardines, soybeans and black-eyed peas, also may provide hefty amounts of calcium. 
 

U.S. News and World Report 
Your family's health, March 1999 Pg 15