Coffee, tea, soft drinks and other caffeinated drinks help many people start the day, remain alert in the afternoon and stay awake in the evening. However, according to the National Institute of Health, caffeine may interfere with the absorption of calcium which is needed by the body to maintain health.
Caffeine comes from leaves, berries, and roots of over 60 plant species, including tea leaves, kola nuts, coffee beans and cocoa beans. For thousands of years, humans have used caffeine, which acts as a mild stimulant to improve mental alertness.
Caffeine intake slightly increases the amount of calcium excreted through urine, but to date, medical experts have not decisively shown that caffeine intake correlates with decreased bone density. For example, the March 1997 issue of the “New England Journal of Medicine” concluded that caffeine consumption presents a risk factor for hip fractures. However, the August 2000 issue of the “Journal of the American College of Nutrition," the April 2000 issue of the “Journal of Bone and Mineral Research" and the 2009 issue of the “Journal of the American Dietetic Association” did not find an association between bone mineral loss and caffeine.
Great sources of calcium include dairy products, calcium fortified foods, and calcium fortified beverages. Bones and teeth contain ninety-nine percent of the body's calcium. In addition, calcium builds and maintains healthy bones, clots blood, sends nerve messages and contracts muscles. The National Academy of Science recommends adult men and women consume between 1,000 milligrams to 1,200 milligrams of calcium daily.
According to the Office of Dietary Supplements, the amount of caffeine in one cup of coffee causes a loss of calcium in the urine equivalent to about one tablespoon of milk. To make up for this loss, add milk to coffee or incorporate additional calcium containing products throughout the day.
To maintain healthy bones, consume the recommended amount of calcium daily. In addition, limit caffeine to no more than 300 milligrams per day -- 16 ounces of brewed coffee, 32 ounces of brewed tea, or six, 12 ounce cans of most caffeinated soft drinks.
- American Dietetic Association; Comparison between Dietary Assessment Methods for Determining Association between Nutrient Intakes and Bone Mineral Density in Postmenopausal Women
- Journal of the American College of Nutrition; Bone Status Among Postmenopausal Women with Different Habitual Caffeine Intakes: a Longitudinal Investigation
- Journal of Bone Mineral Research; Risk Factors for Longitudinal Bone Loss in Elderly Men and Women: The Framingham Osteoporosis Study
- National Academy of Science: Calcium