Calcium May Lower Risk of Digestive Cancers by Jennifer Wider, MD
It has long been established that calcium builds stronger bones, but there’s another good reason to get your daily dose. A new study from the Archives of Internal Medicine reveals that dairy and other food rich in calcium may lower a person’s risk of digestive cancers.
Researchers at the U.S. National Cancer Institute in Bethesda, Maryland handed out questionnaires to roughly 500,000 participants to examine their dietary habits. Their findings revealed that a high calcium intake was linked to a lower risk of digestive tract cancers, including colon cancer.
The lead researcher, Yikyung Park, Sc.D., and colleagues write: “In both men and women, dairy food and calcium intakes were inversely associated with cancers of the digestive system.” They also noted that: “supplemental calcium intake was inversely associated with colorectal cancer risk.”
The effects of calcium were exceptionally strong among the female participants in the study. Women who consumed 1,800 mg or more of calcium per day had almost a 25 percent lower risk of colorectal and other digestive system cancers than women who consumed less than 500 mg per day.
Calcium is the most common mineral in the body and it plays a vital role in many processes including blood clotting, muscle contraction, bone and tooth formation and nerve impulse transmission. This study is among several other recent studies touting the benefits of calcium in the prevention of diseases including cancer.
The study comes along at a time when the rates of obesity are sharply rising in the United States. According to the National Cancer Institute (NCI), obesity is a major risk factor for certain diseases, including digestive cancers. “Overweight and obese individuals are two times more likely than healthy weight people to develop a type of esophageal cancer called esophageal adenocarcinoma. A smaller increase in risk has been found for gastric cardia cancer, a type of stomach cancer that begins in the area of the stomach next to the esophagus.” In addition, data from the NCI also reveals that colon cancer occurs more frequently in people who are obese.
Aside from obesity, other risk factors for cancers of the digestive tract include:
• Age
• Family history of disease
• Lifestyle choices (including smoking and moderate to heavy alcohol consumption)
• Personal history of gastroesophageal reflux disease (for esophageal cancer)
• Personal history of colorectal polyps (for colorectal cancer)
• Inflammatory bowel disease (for colorectal cancer)
• Certain occupations (Workers in the coal, metal, and rubber industries seem to have a higher risk of getting stomach cancer)
Knowing your risk for a certain disease can make a significant difference in prevention. And although the researchers in the study call for more studies to confirm their findings, it seems likely that the benefits of calcium extend deeper than our bones. It is always wise to check with your health care professional before making significant changes to your dietary regimen.
Sources
Park, Y, et al. Dairy Food, Calcium, and Risk of Cancer in the NIH-AARP Diet and Health Study. Arch Intern Med. 2009;169(4):391-401.
Polednak AP. Trends in incidence rates for obesity-associated cancers in the U.S. Cancer Detection and Prevention 2003; 27(6):415–421.
Murphy TK, Calle EE, Rodriguez C, Kahn HS, Thun MJ. Body mass index and colon cancer mortality in a large prospective study. American Journal of Epidemiology 2000; 152(9):847–854.
Martinez ME, Giovanucci E, Speigelman D, et al. Leisure-time physical activity, body size and colon cancer in women. Nurses’ Health Study Research Group. Journal of the National Cancer Institute 1997; 89(13):948–955.
To contact this physician or to learn more about digestive cancers visit the Society for Women's Health Research at http://www.womenshealthresearch.org/ or call (202)223-8224.
