The cost of calcium - Vitamins and Minerals

Nutrition Research Newsletter, Dec, 2002 by J. Keller, A. Lanou, N. Barnard

Calcium, an essential mineral, is needed throughout life. Consumers are influenced by many nutrition authorities to include calcium-rich foods in their daily diets. Adequate intakes of calcium recommended by the Institute of Medicine, National Academy of Sciences, are highest at 1,300 mg for pregnant and lactating women aged 18 years or younger and females and males aged 9 through 18 years; 1,200 mg for adults older than 51 years; and 800 mg for children aged 4 through 8 years. Consumer purchases of both food and supplements are influenced not only by preferences, but also by cost. Until now, there have been no studies assessing the range of consumer prices of commonly available calcium-containing products.

A study was undertaken to assess the cost of calcium from a wide variety of sources in geographically diverse locations across the United States, while controlling for seasonal variation. The study was designed to take into account the fact that calcium absorption varies greatly among calcium-containing foods and thus to provide useful information to consumers and health professionals regarding the consumer cost of bioavailable calcium in US grocery stores.

In Seattle, WA; San Francisco, CA; Raleigh, NC; New York, NY; and Washington, DC researchers estimated the cost of absorbable calcium from foods and supplements. In each city, 2 large grocery stores were selected and trained observers recorded retail price. The observers were instructed to record regular, nonsale prices of generic or store-brand items in the most economical product size. Prices were recorded twice, once in September and once in March to allow for seasonal variations. For each product, gross and estimated absorbable calcium per serving and cost per 300 mg estimated absorbable calcium were calculated. The calculations were based on the best available calcium content and absorption data and should be considered estimates as calcium absorption is largely based upon the other nutrients and foods consumed at the meal. Prices were recorded for varying milk and dairy products, calcium-fortified soy milk, calcium-fortified orange juice from frozen concentrate, tofu processed with calcium chloride, flesh and frozen green leafy vegetables, dried white beans, Total cereal (General Mills, Inc, Minneapolis, Minn), Special K Plus cereal (Kellogg Co, Battle Creek, Mich), calcium citrate supplements, calcium carbonate supplements, and generic and brandname Tums (GlaxoSmithKline, Research Triangle Park, NC and Philadelphia, PA).

Following analysis, calcium carbonate supplements emerged as the least expensive source of calcium, at roughly one-third the cost of the least expensive food source of calcium. The least expensive food sources of calcium were Total cereal, skim milk, and calcium-fortified orange juice from frozen concentrate. This is useful information, not only for health care professionals, but also for the general consumer who should strive to meet their recommended calcium intake daily.

J. Keller, A. Lanou, N. Barnard. The consumer cost of calcium from food and supplements. J Am Diet Assoc; 102:1669-1671 (November, 2002). [Correspondence: J. L. Keller, Physicians Committee for Responsible Medicine, 5100 Wisconsin Ave, Ste 400, Washington, DC 20016].