JAMA and Archives Journals
Calcium associated with lower risk of cancer in women
Women with higher intake of calcium
appear to have a lower risk of cancer overall, and both men and women
with high calcium intakes have lower risks of colorectal cancer and
other cancers of the digestive system, according to a report in the
February 23 issue of
Archives of Internal Medicine, one of the
is known to benefit bone health, according to background information in
the article. Because of this, the Institute of Medicine recommends
1,200 milligrams of calcium for adults age 50 and older, and the 2005
dietary guidelines for Americans recommend 3 cups per day of low-fat or
fat-free dairy products. Studies of dairy products, calcium intake and
cancer have revealed different results for different cancer sites.
Park, Sc.D., of the National Cancer Institute, Bethesda, Md., and
colleagues analyzed data from 293,907 men and 198,903 women who
participated in the National Institutes of Health-AARP Diet and Health
Study. Participants took a food frequency questionnaire when they
enrolled in the study between 1995 and 1996, reporting how much and how
often they consumed dairy and a wide variety of other foods and whether
they took supplements. Their records were then linked with state cancer
registries to identify new cases of cancer through 2003.
an average of 7 years of follow-up, 36,965 cancer cases were identified
in men and 16,605 in women. Calcium intake was not associated with
total cancer in men but was in women—the risk decreased in women with
intake of up to 1,300 milligrams per day, after which no further risk
reduction was observed.
"In both men and women, dairy food
and calcium intakes were inversely associated with cancers of the
digestive system," the authors write. The one-fifth of men who consumed
the most calcium through food and supplements (about 1,530 milligrams
per day) had a 16 percent lower risk of these types of cancer than the
one-fifth who consumed the least (526 milligrams per day). For women,
those in the top one-fifth of calcium consumption (1,881 milligrams per
day) had a 23 percent lower risk than those in the bottom one-fifth
(494 milligrams per day). The decreased risk was particularly
pronounced for colorectal cancer. Calcium and dairy food intake was not
associated with prostate cancer, breast cancer or cancer in any other
anatomical system besides the digestive system.
which is relatively high in potentially anticarcinogenic nutrients such
as calcium, vitamin D and conjugated linoleic acid, has been postulated
to protect against the development of colorectal and breast cancer,"
the authors write. Calcium has been shown to reduce abnormal growth and
induce normal turnover among cells in the gastrointestinal tract and
breast. In addition, it binds to bile and fatty acids, potentially
reducing damage to the mucous membrane in the large intestine.
conclusion, our findings suggest that calcium intake consistent with
current recommendations is associated with a lower risk of total cancer
in women and cancers of the digestive system, especially colorectal
cancer, in both men and women," the authors write.
Arch Intern Med. 2009;169:391-401. Available pre-embargo to the media at www.jamamedia.org.)
Note: The study was funded by the Intramural Research Program of the
National Cancer Institute, National Institutes of Health. Please see
the article for additional information, including other authors, author
contributions and affiliations, financial disclosures, funding and