Calcium makes up about 1.5% to 2.0% of the human body, with about 98% in the bones, 1% in the teeth, and the rest in tissues and the circulatory system. It has become a popular fortification nutrient in foods and beverages â€” in everything from cereal and orange juice to soup and bread â€” because of its role in preventing osteoporosis, a disease that results in bone-mass loss that makes bones susceptible to fractures. We require it throughout life: first to build bones, then to maximize bone density, to maintain adult bone mass and, later in life, to minimize bone loss and prevent osteoporosisâ€™s debilitating effects. The National Academy of Sciences, Washington, D.C., recommends that children ages 4 to 8 should consume 800 mg calcium/day, preteens and teens ages 9 to 18 need 1,300 mg, adults 19 to 50 need 1,000 mg, and those 51 and older require 1,200 mg. Calcium can be obtained from dairy products and other naturally calcium-rich foods in sufficient quantities to meet these daily requirements, but that just isnâ€™t happening, hence the rising importance of calcium-fortified products. According to the National Osteoporosis Foundation (NOF), Washington, D.C., in 2002, more than 10 million people suffered from osteoporosis; this figure might climb to 12 million by 2010 if the trend continues. Itâ€™s estimated that about 75% of the U.S. population currently has calcium-deficient diets. As the awareness and incidence of osteoporosis continues to grow, so does the need for calcium-fortified products. Ideally, most nutritionists recommend foods, especially lowfat dairy products, as the best source of calcium. Milk, yogurt and cheese provide about 25% to 30% of the RDA per serving (approximately 250 to 350 mg calcium/8 oz. of milk). However, the National Dairy Council, Rosemont, IL, notes: â€œLow intake of dairy foods â€¦ is largely responsible for Americansâ€™ low calcium intake. Americans are consuming an average of only 1.5 servings of dairy foods a day, or half the number of servings recommended in the Food Guide Pyramid.â€� So unless eating patterns drastically change, calcium fortification is here to stay. Calcium ingredients range from a variety of GRAS salts with various calcium contents â€” such as carbonate (40% Ca), chloride (27%), citrate (21%), gluconate (14%), lactate (14%) and phosphates (mono-, di- and tribasic with 17% to 38%); to dairy calcium (including high-calcium milk protein, and milk minerals), with calcium contents from 2% to approximately 25%; to new forms, such as a calcium amino acid, malic acid chelate complex, and calcium fumarate (19%). Choosing the best calcium form for food fortification depends on a number of technical considerations, such as bioavailability, solubility, taste, palatability, stability and effects on the final product, as well as cost and consumer preference.