Vegetarians and Cancer Risk: New Research Findings
A comprehensive study has found that vegetarians have up to a third lower risk of developing five different types of cancer. Researchers from Oxford University analyzed data from 1.8 million people, revealing that those who avoid meat are less likely to encounter various cancers, including breast and prostate cancer.
The scientists suggested that “meat itself” could play a significant role in cancer risk, recommending a diet rich in whole grains, pulses, fruits, and vegetables while limiting processed meats.
In comparison to meat eaters, vegetarians showed a 21% reduced risk of pancreatic cancer, a 9% lower risk for breast cancer, a 12% decrease in prostate cancer risk, a 28% lower chance of developing kidney cancer, and a 31% reduced likelihood of multiple myeloma, which is a type of blood cancer.
Each year, these cancers result in approximately 41,800 deaths and account for 143,000 new cases in the UK alone. However, it’s not all positive news for vegetarians; they were nearly twice as likely to develop the most common kind of oesophageal cancer, while vegans showed a heightened risk for bowel cancer. This might be due to missing essential nutrients like calcium and vitamin B12, which may serve as protective factors, according to the researchers.
Those who consume only poultry instead of red meat tend to have slightly lower cancer risks than those who eat all types of meat.
This study, published in the British Journal of Cancer, combined data from prior research over two decades involving mainly participants from the UK and the US, who completed food questionnaires to evaluate their diets.
Out of the total participants, 1.64 million consumed meat, averaging about 50 grams daily—roughly the amount in a sausage or two slices of ham.
Tim Key, an emeritus professor of epidemiology at Oxford Population Health, noted that vegetarians likely have lower cancer risks not just because they eat healthier foods but also due to the impact of meat itself.
He remarked, “I feel the differences seem tied more to the meat than to vegetarians just having healthier diets.” This aligns with existing knowledge that processed meats, like bacon and salami, are linked to higher chances of bowel cancer and possibly stomach cancer as well.
Various factors—including chemical changes during cooking and internal processes that can harm cell DNA—could be why certain meats are linked to cancer. Additionally, preservatives like nitrates in processed meats may further increase risks.
Key continued, “With around three million vegetarians in the UK and increasing interest in vegetarianism globally, it’s important to recognize that cancer remains a leading cause of death worldwide. Dietary habits focusing on fruits, vegetables, and fiber while avoiding processed meats can potentially lower cancer risks. Our findings provide essential insights on vegetarian diets’ benefits and risks.”
This research is notable as it quantifies how dietary patterns influence cancer risks across 17 types of the disease, accounting for other factors like obesity and alcohol consumption that also affect risk levels.
Among vegans, the research indicated a considerably higher risk of bowel cancer relative to meat consumers, possibly due to lower average calcium intake. Studies have shown that calcium may lessen the risk of bowel cancer, with one significant glass of milk a day linked to a 17% reduction in risk.
Aurora Pérez-Cornago, the chief investigator of the study, stated, “Vegetarians generally consume more fruits, vegetables, and fiber compared to meat eaters and avoid processed meats, which may contribute to lower cancer risks. However, the elevated risk of certain cancers among vegetarians and vegans might stem from insufficient intake of specific nutrients found predominantly in animal products. Further research is necessary to understand these cancer risk variations better.”
This study, funded by the World Cancer Research Fund, aims to provide trustworthy evidence as individuals contemplate reducing meat consumption, offering the most extensive findings to date regarding vegetarian and non-meat dietary patterns and their connections to cancer risks.
Dr. Helen Croker from the World Cancer Research Fund International emphasized the significance of this research, noting that while non-meat diets are associated with lower risks for certain cancers, this isn’t the case for all types, illustrating the complex relationships between dietary habits and cancer varieties.
