Eating less meat linked with lower overall cancer risk

Vegetarians, fish-eaters, and low meat-eaters have a reduced risk of developing all cancers in comparison to regular meat-eaters, according to a new study.

The research, published in the journal BMC Medicine and conducted by researchers at the University of Oxford, aimed to assess the associations of vegetarian and non-vegetarian diets with risks of all cancer, including colorectal cancer, postmenopausal breast cancer, and prostate cancer. Researchers also sought to explore the role of potential mediators between these associations.

By analyzing data collected from 472,377 British adults who were between 40 and 70 years of age, researchers calculated the incidence of new cancers that developed over an average period of 11 years using health records. Participants were asked to report how frequently they ate meat and fish; and researchers accounted for diabetes status, as well as sociodemographic, socioeconomic, and lifestyle factors in their analysis.

Of the participants evaluated for the study, 52 percent of participants ate meat more than five times per week, 44 percent ate meat five or less times per week, two percent ate fish but not meat, and two percent were vegetarian or vegan. Twelve percent or 54,961 of the participants developed cancer during the study period.

The researchers found that the overall cancer risk was two percent lower among those who ate meat five times or less per week, 10 percent lower among those who ate fish but not meat, and 14 percent lower among vegetarians and vegans, compared to those who ate meat more than five times a week.

When breaking those findings down into specific cancers, researchers concluded that those who ate meat five times or less per week had a nine percent lower risk of colorectal cancer, compared to those who ate meat more than five times a week. The risk of prostate cancer was 20 percent lower among men who ate fish but not meat and 31 percent lower among men who followed a vegetarian diet. Post-menopausal women who followed a vegetarian diet had an 18 percent lower risk of breast cancer, compared to those who ate meat more than five times per week.

According to researchers, the observational nature of this study does not allow for conclusions about a causal relationship between diet and cancer risk.