Featured Research

from universities, journals, and other organizations

Calcium May Protect Women From Cancer

Date:
January 29, 2005
Source:
University Of Minnesota
Summary:
A University of Minnesota Cancer Center study found that women consuming more than 800 milligrams of calcium each day reduced their risk of colorectal cancer by as much as 26 to 46 percent. A 26 percent reduction in risk of colorectal cancer occurred regardless of whether the calcium intake was from diet or supplement.

A University of Minnesota Cancer Center study found that women consuming more than 800 milligrams of calcium each day reduced their risk of colorectal cancer by as much as 26 to 46 percent. A 26 percent reduction in risk of colorectal cancer occurred regardless of whether the calcium intake was from diet or supplement. Among women who consumed high levels of calcium from both diet and supplements, the risk reduction was almost double that observed for calcium from either source by itself.

The results of the study appear in this month's Cancer Epidemiology, Biomarkers and Prevention journal. Andrew Flood, Ph.D., epidemiologist with the University of Minnesota Cancer Center and School of Public Health, led the study in collaboration with the National Cancer Institute (NCI).

The study involved 45,354 women in the United States who did not have a history of colorectal cancer. The women were categorized into groups according to information they provided about their diets and lifestyles. The women averaged 61.9 years of age upon entering the study and they were followed in the study for an average of 8.5 years. This study began in 1987 and closed in 1997. During that time, 482 women in the study developed colorectal cancer.

"It is especially notable that the risk reduction was present regardless of the source of the calcium, and that simultaneously consuming high levels of calcium from both diet and supplements further reduced risk," Flood said. "These observations suggest that it was the calcium per se, and not merely dairy products or some other variable that accounted for the reduction in risk."

The findings provide further evidence in a growing body of research that indicates a link between calcium and prevention of colorectal cancer. This study is good news for women because they comprise about half of the approximately 150,000 people in the United States diagnosed annually with colorectal cancer. The cancer ranks as the second leading cause of cancer death, and the risk of contracting it increases with age.

Flood notes that more research needs to be done to understand why and how calcium provides protection against colorectal cancer in some women.

"We really don't know at this point," Flood said. "There are currently two main theories. One is that calcium has the ability to neutralize secondary bile acids that are produced during the digestion of fat and are highly irritating to the cells in the lining of the colon. The evidence in support of this theory is not very strong.

"An alternate theory is that calcium has a direct impact on a whole series of biochemical pathways within the cells that line the colon and rectum. These pathways play important roles in regulating how these cells grow and mature and thus, can be important components of the cancer process."

To put the study results in perspective, Flood says consuming a diet rich in calcium – one that provides at least 800 mg per day, which is actually lower than the current recommended daily allowance of 1,200 mg per day--is a safe and effective way for women to help guard themselves against colorectal cancer.

As for the benefit of calcium for men, he said, "The results of this study are consistent with other studies that show calcium reduces risk of colorectal cancer in both women and men. A note of caution for men, however, is that dairy foods, the primary source of calcium in the U.S. diet, have been linked in some studies to increased risk of prostate cancer."

<b>More about the study</b>

The 45,354 women in this study were selected from the Breast Cancer Detection Demonstration Project (BCDDP), which was a breast cancer screening program conducted jointly by NCI and the American Cancer Society between 1973-1980.

The women initially completed a 62-item questionnaire that assessed their usual daily diet, lifestyle habits and patterns, and use of over-the-counter nonsteroidal anti-inflammatory medicines. A separate series of questions asked about their intake of calcium from supplements, whether multivitamins or calcium-specific.

The information received was used to categorize the women into five equally sized groups. The groups were ranked in order of increasing calcium intake, based on the dietary practices the women reported at the start of the study.

* Women in the lowest group consumed less than 412.3 mg of calcium from diet each day.

* Compared to the low-consuming group, women in the four higher groups (412.4-528.9 mg/d; 529.0-656.2 mg/d; 656.3-830.9 mg/d; and greater than 830.9 mg/d) all showed reduced risk of developing colorectal cancer over the course of the study.

* Women in the highest group of dietary calcium intake – greater than 830 mg/d – had a 26 percent lower risk of developing colorectal cancer compared to women in the lowest group.

The women also were divided into groups based on their intake of calcium from supplements. Women who reported consuming 800 mg/d of calcium from supplements had a 24 percent lower risk of developing colorectal cancer than women who took no calcium from supplements. The researchers further found that high intake of calcium from both diet and supplements reduced risk even more than calcium from either source alone. Women who consumed more than 412.4 mg/d of calcium from diet and also consumed more than 800 mg/d from supplements had a 46 percent lower risk of colorectal cancer than women who consumed less than 412 mg/d from diet and less than 800 mg/d from supplements.

This study was funded by NCI. In addition to Andrew Flood, researchers on the study were Ulrike Peters, Fred Hutchinson Cancer Center, Seattle; and Nilanjan Chatterjee, James Lacy, Jr., Catherine Schairer and Arthur Schatzkin, all with NCI in Bethesda, MD

###

The Cancer Center at the University of Minnesota is a National Cancer Institute-designated Comprehensive Cancer Center. Awarded more than $80 million in peer-reviewed grants during fiscal year 2003, the Cancer Center conducts cancer research that advances knowledge and enhances care. The center also engages community outreach and public education efforts addressing cancer. To learn more about cancer, visit the University of Minnesota Cancer Center Web site at http://www.cancer.umn.edu. For cancer questions, call the Cancer Center information line at 1-888-CANCER MN (1-888-226-2376) or 612-624-2620 in the metro area.


Story Source:

The above story is based on materials provided by University Of Minnesota. Note: Materials may be edited for content and length.


Cite This Page:

University Of Minnesota. "Calcium May Protect Women From Cancer." ScienceDaily. ScienceDaily, 29 January 2005. <www.sciencedaily.com/releases/2005/01/050128222241.htm>.
University Of Minnesota. (2005, January 29). Calcium May Protect Women From Cancer. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2005/01/050128222241.htm
University Of Minnesota. "Calcium May Protect Women From Cancer." ScienceDaily. www.sciencedaily.com/releases/2005/01/050128222241.htm (accessed April 20, 2014).

Share This



More Health & Medicine News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins