The Science Doesn’t Support IARC Decision

Philip Ellis_headshotBy Philip Ellis, Wyoming Rancher, NCBA President

We learned this week that the International Agency for Research on Cancer (IARC), has voted to tell the world that they believe processed meats are a human carcinogen. Similarly, they have decided red meat is a “probable carcinogen.” Let me be clear, this group did not conduct new research during their meeting, they simply reviewed existing evidence, including six studies submitted by the beef checkoff. That evidence had already been reviewed and weighed by the medical and scientific community. The science reviewed by IARC simply does not support their decision.

We know that there isn’t clear evidence to support IARC’s decision because the beef checkoff has commissioned independent studies on the topic for a decade. In fact, countless studies have been conducted by cancer and medical experts and they have all determined the same thing: No one food can cause or cure cancer. But that hasn’t prevented IARC from deciding otherwise.

Since IARC began meeting in 1979, these experts have reviewed more than 900 compounds, products and factors for possible correlation with cancer. To date, only one product (caprolactam, which is a chemical primarily used to create synthetic fibers like nylon) has been granted a rating of 4, which indicates it is “probably not carcinogenic to humans.” Most other factors or products that have been examined by the body, including glyphosate, aloe vera, nightshift work and sunlight have fallen into three categories: 2B “possibly carcinogenic to humans,” 2A “probably carcinogenic to humans,” or 1 “carcinogenic to humans.”

It seemed likely from the beginning that we’d find ourselves here. We knew the deck was stacked against us, so the beef industry and others have long been working on providing credible research that would support what many others outside our industry have already verified: A full, fair and unbiased examination of the entire body of research does not support a finding that red or processed meats cause cancer. This conclusion isn’t mine alone and you can evaluate the information for yourself. We’ve posted the studies reviewed by IARC on the website: At NCBA, our team of experts has also been working with our state partners and other industry organizations to mount a full-scale defense of beef.

As just one example of the work we’ve done, we commissioned a study with the same body of research reviewed by IARC. Our study engaged a panel of 22 epidemiologists from the United States and abroad who were recruited by a third-party research group. Participants in the study averaged 22 years of experience and the full panel had a combined total of 475 years of experience. They were provided with a meta-analysis graph which showed data for a specific exposure and a specific human disease outcome, but the specific human disease outcome and exposure were not revealed. In other words, they plotted the results of the study findings on a graph, without telling the participants what product the studies examined. Of the 22 participants in the study, 21 (or 95 percent) said their assessment of the magnitude of the association was weak. Of the 22 epidemiologists, only 10 (or 45 percent) said there was even a possible association. Perhaps most importantly, the epidemiologists agreed that, given the evidence provided, there is not sufficient evidence to make public health recommendations.

Cancer is a complex subject and no one understands fully what causes it or how it can be prevented. Despite billions of dollars spent on research, we only know that no one food can cause or prevent cancer. We also know, thanks in part to decades of producer-funded work on the subject, that when people lead overall healthy lifestyles and maintain a healthy weight, they reduce their risks for chronic diseases, such as cancer, and our team and our state partners are hard at work on this topic to be certain that consumers and their influencers know and understand that beef should remain in their diets, regardless of what IARC might say.

Science Does Not Support International Agency Opinion on Red Meat and Cancer

beef consumer demand meat caseAn international committee assigned to review all of the available evidence on red meat and cancer risk were divided on their opinion whether to label red meat a “probable” cause of cancer, according to the Beef Checkoff nutrition scientist and registered dietitian who observed the International Agency for Research on Cancer (IARC) process. After seven days of deliberation in Lyon, France, IARC was unable to reach a consensus agreement from a group of 22 experts in the field of cancer research, something that IARC has proudly highlighted they strive for and typically achieve. In this case, they had to settle for “majority” agreement.

“Cancer is a complex disease that even the best and brightest minds don’t fully understand,” says Shalene McNeill, PhD, RD. “Billions of dollars have been spent on studies all over the world and no single food has ever been proven to cause or cure cancer. The opinion by the IARC committee to list red meat as a probable carcinogen does not change that fact. The available scientific evidence simply does not support a causal relationship between red or processed meat and any type of cancer.”

Most scientists agree that it is unrealistic to isolate a single food as a cause of cancer from a complex dietary pattern further confounded by lifestyle and environmental factors.

“As a registered dietitian and mother, my advice hasn’t changed. To improve all aspects of your health, eat a balanced diet, which includes lean meats like beef, maintain a healthy weight, be physically active and, please don’t smoke,” says McNeill.

While IARC represents a select group of opinions, it doesn’t always represent consensus in the scientific community.

A large meta-analysis, published online in May in the Journal of the American College of Nutrition, analyzed the relationship between red meat intake and risk for colorectal cancer and concluded “red meat does not appear to be an independent predictor of CRC risk,” according to Dominik Alexander, PhD, MSPH, the epidemiologist who conducted the research on behalf of the Beef Checkoff.

“There are a constellation of factors that are associated with the probability of getting cancer, which include age, genetics, socioeconomic characteristics, obesity, lack of physical activity, where you grew up, alcohol consumption, smoking and even your profession,” says Alexander. “The bottom line is the epidemiologic science on red meat consumption and cancer is best described as weak associations and an evidence base that has weakened over time. And most importantly, because red meat is consumed in the context of hundreds of other foods and is correlated with other behavioral factors, it is not valid to conclude red meat is an independent cause of cancer.”

According to Alexander, studies in nutritional epidemiology can be highly prone to bias such as self-reported dietary intake, for which habits may change over time. Because of this, associations reported in nutritional epidemiology may be surrounded by uncertainty. For instance, most, if not all, of the observational studies with red meat are limited by confounding factors; for example, studies have shown that people who consume the most red meat are the most likely to smoke, eat fewer fruits and vegetables and be overweight or obese – all of which may confound the relationship between eating red meat and risk of cancer.

Also, more recent studies in large cohorts are now finding either no association or non-significant findings between red meat and cancer. For example, a recent study out of Harvard using the well known The Nurses’ Health Study (NHS) and The Health Professionals Follow-up Study (HPFS) found unprocessed meat intake had an inverse association with distal colon cancer and a weak, statistically non-significant, positive association with risk of proximal colon cancer.

In addition, gold standard nutrition evidence, such as the Women’s Health Initiative and the Polyp Prevention Trial, two large, multi-year randomized controlled dietary interventions, found that a 20 percent reduction in red meat consumption did not reduce the risk of colorectal cancer and/or had no effect on adenoma recurrence in the large bowel. These studies were disregarded from the IARC review.

“Given the weak associations in human studies and lack of evidence in animal studies it is hard to reconcile the committee’s vote,” says nutritional toxicologist James Coughlin, PhD, CFS. “Of more than 900 items IARC has reviewed, including coffee, sunlight and night shift work, they have found only one ‘probably’ does not cause cancer according to their classification system.”

Coughlin, a toxicologist with more than 40 years of experience in meat and cancer, is critical of the IARC review process due to the lack of transparency, selective inclusion or exclusion of studies and broad interpretation of study results that are inconsistent with the conclusions of the study authors.

“In my experience as an observer to an IARC working group, the process typically involves scientists who have previously published research on the substance being reviewed and may have a vested interest in defending their own research” says Coughlin. “In the case of red and processed meat, the overall scientific evidence simply does not support their conclusion.”

–NCBA Press Release

NCBA: Dietary Guidelines Recommendations are Misleading

WASHINGTON  – Yesterday, the U.S. Department of Health and Human Services and the U.S. Department of Agriculture released the 2015 Dietary Guidelines Advisory Committee’s report. This report is a recommendation to the Secretaries as they develop the 2015 Dietary Guidelines for Americans that will be released later this year. Unfortunately, the report is inconsistent, and if adopted will lead to conflicting dietary advice. On one hand, the Committee has endorsed the Mediterranean style diet, which has higher red meat levels than currently consumed in the U.S.; and on the other hand, they have left lean meat out of what they consider to be a healthy dietary pattern.

Dr. Shalene McNeill, Registered Dietitian and Nutrition Scientist with National Cattlemen’s Beef Association said the recommendation that a healthy dietary pattern should be lower in red meat is not consistent with scientific evidence and would be unsound dietary advice.

“Lean meat is red meat. Today’s beef supply is leaner than ever before with more than 30 cuts of beef recognized as lean by government standards,” said McNeill. “The protein foods category, which includes meat, is the only category currently consumed within the current guidelines, and it is misleading to conclude that a healthy dietary pattern should be lower in red meat.”

According to the report, “dietary patterns with positive health benefits are described as high in vegetables, fruit, whole grains, seafood, legumes, and nuts; moderate in low- and non-fat dairy products; lower in red and processed meat; and low in sugar-sweetened foods and beverages and refined grains.”

Unfortunately, the statement disregards the positive role of lean meat. Lean beef is one of the most nutrient rich foods, providing high levels of essential nutrients such as zinc, iron and protein, as opposed to empty calories.

Dr. Richard Thorpe, Texas medical doctor and cattle producer, said the key to a healthy lifestyle is building a balanced diet around the healthy foods you enjoy eating, coupled with physical activity.

“It is absurd for the Advisory Committee to suggest that Americans should eat less red meat and focus so heavily on plant-based diets,” said Thorpe. “The American diet is already 70 percent plant based and to further emphasize plant-based diets will continue to have unintended consequences. The Advisory Committee got it wrong in the ‘80s advising a diet high in carbs, and look at what that got us – an obesity problem. My colleagues and I commonly encourage people to include lean beef more often for their health, not less.”

Thorpe added, “We are disappointed the Advisory Committee would go outside the purview and expertise of nutrition/health research to bring in topics such as sustainability. We urge the Secretaries to reject the Advisory Committee’s recommendations on topics outside of diet and health.”

Lean meat plays an important role in the American diet and science shows it needs to be recognized as part of a healthy dietary pattern just as it was in the 2010 Dietary Guidelines for Americans. On behalf of U.S. cattle producers that work each and every day to provide a nutritious and healthful beef product for consumers, we encourage Secretaries Burwell and Vilsack to reject the Advisory Committee’s recommendation that healthy American diets should be lower in red meat. The process was incomplete with flawed conclusions specific to health benefits of red meat’s role in the American diet.