New research suggests another reason beyond curbing climate change for adopting meatless or low meat diets: they reduce the risk of cancer.
Giving up meat has never been easier than in the last few years; you can now take your pick for a drive-thru window that offers meatless burgers, or find a range of options at supermarkets that make plant-based food an easy stand-in for meat (and other animal products including eggs and dairy).
Reasons for reducing meat vary, but generally, people cite one of three: their health, their ethics, or the planet.
Meat and the climate
The climate crisis is deeply linked to animal consumption. More than 14 percent of all emissions are linked to animal agriculture, making it a leading cause of climate change. By comparison, the aviation industry represents just 2.5 percent of all emissions. In 2019, the Intergovernmental Panel on Climate Change (IPCC) of the United Nations released a report urging the world to reduce their meat consumption to fight climate change.
“We don’t want to tell people what to eat,” Hans-Otto Pörtner, an ecologist who co-chairs the IPCC’s working group on impacts, adaptation, and vulnerability, said of the report. “But it would indeed be beneficial, for both climate and human health, if people in many rich countries consumed less meat, and if politics would create appropriate incentives to that effect.”
Meat production’s problems don’t just start and stop with its contribution to emissions. It’s a tremendous strain on resources including fresh water, cereal grains, antibiotics, and land. In the Amazon, it’s now the leading cause of deforestation, pushing the rainforest into carbon emitter status instead of its long-held title of carbon sink.
Meat and cancer
In the U.S., though, most people that reduce or eschew meat altogether do it for their health. Obesity and type-2 diabetes rates are still sky high in the U.S. despite efforts to bring healthier food options to schools, restaurants, and supermarkets.
The World Health Organization has classified processed meats, including ham, bacon, salami, sausages and hot dogs, as a Group 1 carcinogen. This classification means they’re known to cause cancer, namely colorectal cancer, with a 50 gram daily serving of processed meat linked to an 18 percent increase. Whole-cut red meat including beef, lamb, and pork, has been classified as a Group 2A carcinogen, meaning they’re likely to cause cancer.
Recent findings published in the journal BMC Medicine, connect a diet low in or void of meat to lower overall cancer risks, according to the University of Oxford researchers behind the study.
The researchers looked at data from more than 470,000 British adults between the ages of 40 and 70.
Study participants reported on diet, and, in particular, how frequently they consumed fish and meat. The researchers compared that with new cancers over an 11-year period. The researchers controlled for issues like diabetes, sociodemographic, socioeconomic, and lifestyle factors.
According to the findings, the cancer risk was two percent lower in participants who ate meat five times or less per week compared with people who ate meat more often; ten percent lower for those who ate fish only, and 14 percent lower in vegan or vegetarians who consumed no meat at all.
Specifically, the first group that ate meat no more than five times per week saw a nine percent decreased risk of colorectal cancer. Prostate cancer risks dropped by 20 percent for men in the fish-only group. But in the vegan and vegetarian diet segment, that number dropped to 31 percent. For post-menopausal vegetarian or vegan women, the risk of breast cancer dropped 18 percent—likely a connection to healthier body mass index, the researchers noted.
“Following a vegetarian, pescatarian or low-meat diet may be associated with a lower risk of being diagnosed with cancer,” study co-author Cody Watling told UPI.
“However, further research is needed with larger number of vegetarians and pescatarians to better explore and understand these associations,” said Watling, a doctoral student in cancer epidemiology at the University of Oxford in England.
“There are different compounds that are found in red and processed meat, either through cooking or added during the processing, that may damage cells and therefore could increase the risk of colorectal cancer,” Watling said.
“However, for other cancer types, outside of colorectal, there is no convincing evidence that suggests consuming meat is associated with the risk of other cancers,” he said.
The findings aren’t the first to link a low-meat or no-meat diet to increased health benefits. U.S. News & World Report repeatedly puts the Mediterranean Diet at the top of its healthiest diet lists. The World Health Organization has recommended lower meat diets for years. And the American Heart Association recently updated its dietary guidelines for the first time in 15 years, suggesting a more sustainable plant-forward diet also has the most health benefits.