Saturday Nov 9, 2013 (foodconsumer.org) -- A new study in Cancer Causes & Control suggests that taking glucosamine and chondroitin as dietary supplements may help reduce the risk of developing colorectal cancer.

The current study led by E. D. Kantor from Fred Hutchinson Cancer Research Center in Seattle, WA, USA and colleagues shows that men and women using a combination of glucosamine and chondroitin for more than three years had a 45% reduced risk of colorectal cancer, compared with those who did not take the supplements.

An early study based on the same the VITamins And Lifestyle (VITAL) study cohort in which participants were followed for a shorter period already observed the association between use of glucosamine and chondroitin and reduced risk of colorectal cancer.

For the current study, the researchers analyzed more data from an additional 2-year follow-up and found men and women reporting use of glucosamine and chondroitin on more than four days a day for more than three years were 45% less likely to be diagnosed with colorectal cancer, compared with non-users.

Body mass index modified the association.   Among those who were overweight or obese, but not those who had normal weight or lower weight, there was an inverse association between use of glucosamine and chondroitin and risk of colorectal cancer.  And use of glucosamine alone was not associated with the risk of colorectal cancer significantly.

The researchers concluded "There is great need to identify safe and effective cancer preventive strategies, suggesting that glucosamine and chondroitin may merit further attention as a potential chemopreventive agent."

Glucosamine and chondroitin as dietary supplements have been commonly used for joint pain and osteoarthritis because they have anti-inflammatory properties.  Many forms of cancer are believd to have something to do with inflammation.

There are many things food consumers may do or not do to prevent colorectal cancer.   What can help prevent or treat colorectal cancer include Mediterranean diet, green tea, vitamin D, b vitamins, dietary fiber, fish oil, aspirin, statins, walnuts, flaxseed, curcumin, lycopene or tomatoes, grape seed extract, eating tofu, cruciferous vegetables, garlic, and onions.

What may increase the risk of colorectal cancer include organochlorines, alcohol drinking, cooked meat, red meat, processed meat, prostate cancer treatment, obesity, diabetes, low magnesium and high calcium, trans fat, low carb diet,  and high fat diet.

Colorectal cancer includes rectum cancer and colon cancer.  Both cancers have many features in common and they are often studied and discussed together.  An estimated 102,480 cases of colon cancer and 40,340 cases of rectal cancer are expected to be diagnosed in the United States in 2013.  Colorectal cancer is expected to kill 50,830 men and women in the U.S. this year. (David Liu, PHD)