Low levels of circulating vitamin D are associated with a greater risk of colorectal cancer, European researchers say.
A case-control study found that people in the top fifth of vitamin D levels had 40 percent lower risk for colorectal cancer than those in the bottom fifth, according to Mazda Jenab of the International Agency for Research on Cancer in Lyon, France, and colleagues.
But more research is needed to see if increasing circulating vitamin D can effectively reduce the risk of the disease, they concluded online in the British Medical Journal.
The main role of vitamin D is to maintain calcium levels in cells and bone metabolism, the researchers noted in the journal. But there is some evidence that it may also play a role in cancer control by modulating cell growth and death and by reducing the development of blood vessels to support tumor tissue.
Unfortunately, they said, epidemiological evidence -- mostly based on counting people's dietary intake of vitamin D rather than taking blood circulating levels -- is inconclusive.
To fill the gap, they turned to the European Prospective Investigation into Cancer and Nutrition (EPIC) study, which is prospectively following 520,000 volunteers from 10 European countries.
Jenab and colleagues compared 1,248 people who developed colorectal cancer after enrollment with 1,248 controls who were disease-free.
Dietary and lifestyle data were obtained from questionnaires and researchers measured circulating vitamin D concentrations.
The researchers found:
There was a linear trend for colorectal cancer. Those in the lower fifths of vitamin D levels significantly more likely to get the disease than those in higher fifths.
The same trend was seen for colon cancer but not rectal cancer.
Compared with volunteers with a mid-level concentrations, those in the lowest fifth had a 32 percent increased risk of colorectal cancer.
Higher concentrations were associated with lower risk.
The vitamin D concentration was associated with lower colorectal risk in a dose-response manner, the researchers reported.
The study's strengths include its large size and prospective (following a group of people before any got sick) design, the researchers said. Also levels of circulating vitamin D before a diagnosis of cancer were available for all participants.
On the other hand, follow-up was relatively short, which may mean that some participants with disease already had the illness at the time the samples were taken.
In addition, the study did not control for colorectal screening; however, the investigators said this is not routinely performed in Europe.
Vitamins do a lot of benefit in the body. To avoid cancer like that, we should engage ourselves in healthy lifestyle. So when we get older, our body can defend itself in any disease like cancer. Vitamin D is important but in colon cancer prevention, rich in fiber food is better.
When I saw my Dr last month to go over my recent blood work. He noted that I had low Vit D. He went on to say that it's an epidemic situation!
Not more than 2% of blood results he's done had adequate Vit D levels, he told me! Since, he directed me to take Vit D3, 1000 IU, 3 times a day until my next blood workup in a couple months.
Originally Posted by Phineas
Don't you want to be compared to Chuck Norris? Hmm?? Don't you???
get a good diet, take a multivitamin, should be okay!
gotta also think about all the people with this in their family that vitamin d is not going to help. my friend is 25 and last year he had a tumor in his colon. luckily it was benign, but colon cancer runs in his family and his grandfather died of it. sometimes you just can't avoid everything.