With all the encouragement to eat healthy that’s come out of anti-obesity campaigns, it would make sense that people who eat mostly fruits and vegetables would be ahead of the general population in terms of health. Studies have shown vegetarians live 20 percent longer than the average meat eater, and while this is largely due to the abundance of fruits and veggies they eat, it’s also because they’ve chosen to abstain from meat, which has been shown to cause cancer. Now, a new study shows just how much skipping meat can protect a person from colorectal cancer.
Conducted by researchers at Loma Linda University in California, the study found that it really doesn’t matter what kind of vegetarian a person is, because they all confer a reduced risk by skipping meat. Out of four categories of vegetarians, pescovegetarians — those who also eat fish — saw the lowest risk of developing the deadly cancer, at 49 percent. Vegetarians who also ate milk and eggs (lacto-ovo vegetarians) came in next with an 18 percent lower risk, while vegans had a 16 percent lower risk and semi-vegetarians had an eight percent lower risk, according to a press release. Overall, vegetarians had a 22 percent lower risk of all colorectal cancers.
The researchers said that while science has made great strides in preventing colorectal cancer through screening, prevention through lowering risk factors like a poor diet has remained an important goal — as with many other conditions like obesity. This screening has reduced cancer diagnoses and death rates significantly; however, it remains the second leading cause of cancer death in the United States. It may be overreaching to suggest everyone stop eating meat to prevent colorectal cancer, but even the study participants categorized as nonvegetarians ate less meat than the average American, The Wall Street Journal reported. That suggests the reduced risk might be lower than the study found and gives Americans more of a reason to lower their meat intake.
These nonvegetarians likely ate less meat than the average American because they were Seventh-day Adventists — the religion promotes healthy eating. All 77,659 participants subscribed to the religion, and were part of the Adventist Health Study between 2002 and 2007. At the beginning of the study, they completed food and health questionnaires, which included asking them about the type of vegetarian they were. At an average follow-up of about 7.3 years, the researchers found 380 people had developed colon cancer and 110 had gotten rectal cancer.
Speaking to The Journal, lead researcher Dr. Michael Orlich, an assistant professor of preventive medicine at the university, said study participants still had 34 percent fewer cases of colorectal cancer than the general U.S. population. And while the fact they ate less meat contributed to this, it was also because they ate more plants. “Diets high in fiber are linked with decreased risk, and fiber comes from whole plant foods, so this could be a major reason why the risk is much lower,” Orlich said.
Beyond lowering cancer risk, vegetarian diets have been shown to lower cholesterol, blood pressure, and weight, thus reducing risk of obesity and heart disease, among other chronic diseases. But Orlich’s study shows you don’t need to be a strict vegetarian to reap the benefits. Eating fish adds vital omega-3 fatty acids to a diet, and keeps the brain and heart healthy — it’s also been shown to prevent some cancer. Even a semi-vegetarian diet, which consists of eating plants with the occasional meat, has been shown to reduce heart disease and stroke risk. So, even if you don’t want to quit eating meat, reducing how much of it you eat is better than doing nothing at all.
Source: Orlich M, Singh P, Sabate J, et al. Vegetarian Dietary Patterns and the Risk of Colorectal Cancers. JAMA Internal Medicine. 2015.