A new set of analyses published Monday in the Annals of Internal Medicine challenges the widespread recommendations to cut back on red and processed meats.
Three of the 14 researchers said they support reducing red and processed meats.
Ultimately this new research has come to the same meat consumption recommendation as many other scientists and advisory bodies over recent years, which is to limit red and processed meat to no more than three or four servings per week.
The new research is unsurprisingly proving divisive among scientists as its conclusions seem strangely at odds with the vast number of general nutritional recommendations suggesting health benefits for eating less red and processed meat.
"Based on the research, we can not say with any certainty that eating red meat or processed meat causes cancer, diabetes or heart disease", said senior researcher Bradley Johnston.
Their advice, that adults should continue to eat their current level of red and processed meat, which is about three to four times a week, is contrary to nearly all other guidelines that exist.
The bona fides and expertise of the leadership team and panel were not questioned, but he disputed the criticisms "which appear to be levelled at all other groups which have suggested guidelines in the past, " he said.
In 12 controlled trials involving about 54,000 people, they were unable to find a statistically significant or important association between meat consumption and the risk of heart disease, diabetes, or cancer.
Johnston remarked on how this should affect meat-eaters' diets, telling the BBC: "The right choice for the majority of people, but not everyone, is to continue their meat consumption".
The authors also did an additional systematic review looking at people's attitudes and health-related values around eating red and processed meats. "Meat is not consumed in isolation and it needs to be examined along with the other foods people eat, so you shouldn't only rely on RCTs to study diets".
"Most of the cholesterol-raising saturated fat Americans eat comes from meat and full-fat dairy products such as whole milk cheese", said Alice Lichtenstein, D.Sc., a professor of nutrition at the USDA Human Nutrition Center at Tufts University in Boston and a member of the American Heart Association's Council on Lifestyle and Cardiometabolic Health.
The recommendations are "sure to be controversial, but [they are] based on the most comprehensive review of the evidence to date", Dr. Aaron Carroll, the associate dean for research mentoring, and Tiffany Doherty, an assistant professor, both at the Indiana University School of Medicine who were not part of the reviews, wrote in an accompanying editorial. According to the research, led by Dr Bradley Johnston, an epidemiologist at Dalhousie University in Canada, red meat might not be as harmful as we now think. A weak recommendation means that it's not broadly applicable to everyone, but rather that people should be making their own decisions based on the evidence, he added.
"Regularly eating processed meat, and higher consumption of red meat, increases your risk of colorectal cancer".
Dr David Katz, director of the Yale-Griffin Prevention Research Centre at the Yale University School of Medicine, cited "grave concerns about the potential for damage to public understanding, and public health". But they noted that their own advice is weak, and acknowledged that they didn't take into account factors such as animal welfare and the toll meat production has on the environment.
Registered dietitian Lalitha Taylor says she understands why people might be unsure of what information to trust. "We have had enough of them".
Cancer Research UK said about 5,400 of the 41,804 cases of bowel cancer seen each year in the UK could be prevented if people did not eat processed meat at all.
Quadram's Johnson said people who choose to cut down their meat intake might still improve their health by doing so.