What’s the Best Diet for Preventing Colon Cancer?

A new study set out to see which diet is the best for preventing colorectal cancer. The researchers divided 77,659 people into five dietary groups and followed them for about seven years. . . .

Compared to nonvegetarians who ate meat at least once a week, vegetarians had a full 22% reduced risk of colorectal cancer. The risk of colon cancer was reduced by 19%, and the risk of rectal cancer was reduced by 29%.

Breaking the groups down further, the researchers found that pescatarians (include fish and seafood) had 43% reduced risk, lacto-ovo-vegetarians had an 18% reduced risk, vegans had a 16% reduced risk, and semi-vegetarians (who ate meat less than once a week) had an 8% reduced risk (JAMA Intern Med [on line] 2015.doi.10.1001/jamainternmed.2015.59).

As impressive as these results are, they are probably even more impressive for the average person. Vegetarians had a 22% reduced risk of colorectal cancer compared to people who eat meat at least once a week. But most North Americans eat meat a lot more often than that.

Another study also published this year found that compared to people who eat the least meat, processed meat, and fish, the people who eat the most increased their risk of colorectal cancer by 84%. This study found that plant based diets reduce the risk of colorectal cancer by 45% (Nutrition Journal 2015;14:8).

An earlier study found that people who eat the most red meat and processed meat have a 20% higher risk of colorectal cancer than people who eat the least (Int J Cancer 2009;125:171-80).