What are your chances of developing colorectal cancer?
Five Guardians
What are your chances of developing colorectal cancer?
Take this quick quiz to find out:
- Do you have a close relative (sibling or parent) who has had colon polyps or has been diagnosed with colorectal cancer?
- Are you over age 65?
- Do you smoke?
- Do you drink alcohol?
- Do you exercise infrequently or not at all?
- Is your diet high in processed foods and low in fruits and vegetables?
- Do you live in an industrialized, western society?
As you’ve probably already guessed, colorectal cancer risk rises for every “yes” answer and lowers for every “no” answer. And those who smoke more than 20 cigarettes a day can add a couple more points to their risk score.
Some of the risk factors can’t be altered, of course. If you’re over 65, there’s no way to unring that bell. And while we may fantasize about living in an unspoiled tropical paradise, most of us will remain in our industrialized home sweet home. But when it comes to diet modification, there’s something we can do beyond eating more fruits and vegetables.
A new study from France confirms previous research about five key nutrients that may offer significant protection against the development of colorectal polyps; a precursor of cancer.
Polyp blockers
Researchers at a digestive cancer center in Dijon, France, recently reported on a study in which colorectal polyp risk was compared to intake of dietary vitamins and beta-carotene. (Beta-carotene is a plant chemical that the body converts into vitamin A.)
Nutrient intakes were assessed in two groups: more than 360 subjects with polyps, and about 425 polyp-free subjects. The Dijon team found five nutrients that were associated with a lower risk of colorectal polyps: folate, beta-carotene, and vitamins B-6, C and D.
But beta-carotene received a special note.
Scientists are not yet sure why beta-carotene intake produces adverse effects among smokers. In the e-Alert “Live Long” (10/26/05), I told you about recent studies that show smokers are at higher risk of developing lung cancer when they have a large intake of beta-carotene and a low intake of other antioxidants.
In the Dijon study, data indicated that beta-carotene intake might increase colorectal polyp risk among smokers, while lowering risk among non-smokers. The researchers suggest that smokers avoid high doses of beta-carotene.
Add one more
In previous e-Alerts I’ve noted how calcium intake has also been shown to help reduce the risk of developing colon polyps.
Last year, researchers from the Dartmouth-Hitchcock Medical Center in Lebanon, NH, published an analysis of data collected from 930 patients enrolled in the Calcium Polyp Prevention Study.
All of the study subjects had been diagnosed with colorectal polyps. Divided into two groups, participants received either a 1,200 mg daily supplement of calcium carbonate, or a placebo. Two colonoscopies were conducted approximately one year and four years after each subject’s initial exams.
The researchers found that while calcium supplements may provide some protection against the development of polyps, the supplements proved most effective against advanced polyps. Subjects who received calcium supplements had generally fewer polyps compared to the placebo group. But as the lead author of the study, Dr. John A. Baron told Health Day News, calcium may help lower the risk of advanced polyps by as much as 45 percent.
Sources:
“Tobacco Use and Associations of Beta-Carotene and Vitamin Intakes with Colorectal Adenoma Risk” Journal of Nutrition, Vol. 135, No. 10, October 2005, ncbi.nlm.nih.gov
