From Anaheim, Calif., at a meeting of the American Association for Cancer Research
Taking calcium supplements protects against colorectal cancer even years after a person stops taking them, a study finds.
Starting in the early 1990s, scientists randomly assigned 930 patients with a history of precancerous growths in the colon or rectum to receive either a daily calcium tablet or an inert pill. Researchers ended the calcium supplementation in 1997.
Over the subsequent 5 years, participants regularly completed follow-up questionnaires about health and lifestyle, and 597 participants had colonoscopies. The data showed that people who had been in the calcium group had only two-thirds as many precancerous colorectal growths, often called polyps, as did people in the placebo group, says John A. Baron of Dartmouth Medical School in Hanover, N.H.