The study, conducted by the Institute of Social and Preventive Medicine at the University of Zurich in collaboration with researchers from 10 European countries, tracked the diet and disease trends of 450,000 people and concluded that the risk of mortality increased by 18% for every 50g of processed meat consumed a day.
“We estimate that 3% of all premature deaths can be attributed to the high consumption of processed meat,” explained lead author Sabine Rohrmann of the Institute of Social and Preventive Medicine at the University of Zurich.
The researchers surmised that the increased risk of cancer was related to carcinogenic substances, such as nitrosamines, which form when meats are salted, smoked or pickled. They added that processed meats were also high in cholesterol and saturated fat, which have been linked to an increased risk of heart disease.
Benefits of meat
The study, which was published in the BMC Medicine journal, stops short of suggesting people should stop eating meat altogether, pointing out that it is a vital source of vitamins and minerals including B vitamins and iron. “Moderate consumption of up to 40g a day doesn’t increase the mortality risk,” said Rohrmann.
The researchers also admitted that the participants in the study who ate more processed meats also lived a less healthy lifestyle, eating fewer fruit and vegetables, consuming more alcohol, smoking more and doing less sport. However, they claimed that even adjusting for these factors, the findings suggested that people who ate more than 40g of processed meat a day had more risk of dying early than people who ate less than 20g a day.
Tracy Parker, a dietician with the British Heat Foundation said that the fact the people who ate the most processed meat in the study also made other unhealthy lifestyle choices “may have had an impact on the results”. She added that red meat could be enjoyed as part of a balanced diet.
“Opting for leaner cuts and using healthier cooking methods, such as grilling, will help to keep your heart healthy. If you eat lots of processed meat, try to vary your diet with other protein choices such as chicken, fish, beans or lentils,” she said.
This is not the first study not to link red meat, and particularly processed meats, with increased risk of heart disease and cancer. However, researchers and nutritionists have previously pointed out that most of these studies are based on epidemiology, which cannot reliably establish cause and effect due to the myriad of other lifestyle factors that could have influenced the results.
Speaking to Globalmeatnews.com last year, Betsy Booren, American Meat Intitute foundation director of scientific affairs told Globalmeatnews: “All of these studies struggle to disentangle other lifestyle and dietary habits from meat and processed meat and admit they cannot do it well enough to use their conclusions to accurately recommend people change their dietary habits.
"What the total evidence has shown, and what common sense suggests, is that a balanced diet and a healthy body weight are the keys to good health."
Science writer and researcher Gary Taubes also dismissed epidemiology during an interview with Globalmeatnews.com. "To call it science is to do science a disservice. It is pseudo-science, it is quackery," he said.
Taubes pointed out that only controlled clinical experiments can provide definitive proof that increased consumption of certain foods increases the risk of disease.