Eating a portion of processed red meat every day dramatically increases the risk of death from heart disease and cancer, according to a study of more than 120,000 people over almost three decades.
The study, one of the largest ever to consider the link between red meat and premature death, found that one additional serving per day of processed meat - which is equivalent to a hot dog - increased the risk of dying early by 20%.
By consuming one extra serve of unprocessed red meat per day, study participants increased the risk of early death by 13 percent. But by replacing red meat with fish, poultry, nuts, legumes and low-fat dairy, they lowered the risk by 7 to 19 per cent, a team from the Harvard School of Public Health, Boston, found.
The findings are published in the journal Archives of Internal Medicine.
The researchers analysed data from 37,698 men and 83,644 women over 28 years, and documented 23,926 deaths - including 5,910 from heart disease and 9,464 from cancer.
Senior author Professor Frank Hu said they provided “clear evidence that regular consumption of red meat, especially processed meat, contributes substantially to premature death.
"On the other hand, choosing more healthful sources of protein in place of red meat can confer significant health benefits by reducing chronic disease morbidity and mortality.”
Another large-scale study published last year concluded there was a strong link between red meat consumption and bowel cancer. The World Cancer Research Fund/American Institute for Cancer Research’s Continuous Update Project advised that people eat no more than 500g of cooked red meat per week, or around five or six medium serves of roast beef, lamb or pork.
The panel recommended avoiding processed meats, such as ham, smoked meat and hot dogs, altogether.
But Veronique Droulez, marketing nutrition manager for Meat and Livestock Australia, said that participants in the latest US study were “less likely to be physically active, more likely to smoke, drink alcohol and have a higher body mass index. They were more likely to have a higher energy intake and ate less whole grains, fruits and vegetables.
"The scientific evidence to support the role of lean red meat in a healthy diet is robust, nothing in this study proves otherwise.”
Tim Crowe, an Associate Professor in Nutrition at Deakin University, said that even taking into account “confounding factors” such as the possible impact of alcohol, tobacco and exercise, there was “a very clear message coming from all of the research that there’s a strong risk that can most likely be attributed to red meat. So even though we can’t say for 100% certain, there is a link there.
"Eating within the current Australian recommendations of three to four servings per week puts you in the lower risk category. So the best advice is don’t have red meat every day.”
Processed meat should be restricted “very much to an occasional food”, Professor Crowe said. “There are no absolutes in nutrition. It’s all about risk, and if you’re having it very occasionally then the risk remains low.”
Ian Olver, CEO of the Australian Cancer Council and a clinical professor at the University of Sydney, said that population studies could show associations but not causal links. “However in the case of red meat and cancer there are plausible causal links such as the animal fat content causing obesity, and the ways meat is cooked producing carcinogens, as two examples.”