Red Meat Study Raises Red Flags
Our family practice doctors in Delray Beach try to keep you abreast of all the latest news on medical research, and we often cite studies in bringing you this information. We do try, however, to ensure the research is based on sound scientific principles.
There are studies . . .
The problem is, some studies are more reliable than others, due to a number of possible variables: study design, number of study subjects, length of study, control over study subjects, and so on. One component that can affect the outcome of a study is who is paying for it. This may tend to bias the researchers—even subconsciously—who conduct the study.
Nutritional studies are notoriously difficult to design because there’s no way to capture a large population group, control everything they ingest for decades, and monitor their health for the duration. So researchers must either conduct animal studies and extrapolate their findings to humans, or monitor the food intake of a huge number of people (often tens or hundreds of thousands) over the course of decades, and look for patterns in their diet and correlate those to certain health outcomes.
. . . and then there are studies
As we can see, it’s not easy to design a “perfect” study, especially when it comes to nutrition and human behavior. However, when the ones we do have tend to show similar trends over continents, population groups, and decades, medical science tends to view these as “well-established” outcomes.
Such is the case for red meat, including processed meats, which years of research has linked to a higher incidence of cardiovascular disease (CVD) and certain cancers, including colorectal cancer, as we reported here.
But a study last month conducted on the health effects of red meat had critics up in arms, because it suggested that these effects had been exaggerated and that the recommendation to limit the consumption of red meat was unnecessary. This particular study was actually a “meta-review” of 66 other studies conducted on 55 populations, as well as of 73 articles that examined links between red meat and cancer incidence.
It concluded that the risks reported in these earlier studies, while present, were low enough that it wasn’t worth telling people to cut back on red meat consumption.
In the aftermath of the furor this conclusion caused, it was revealed this month that an industry marketing arm of Texas cattle ranchers, the Texas Beef Checkoff program, had funded several studies of the group, which was not disclosed when the study was published.
In addition, the study’s lead author had in the past also challenged the recommendation to limit sugar intake. That study was also funded by the processed food industry, including PepsiCo, Coca-Cola, McDonald’s, and Cargill, according to the New York Times.
Who to believe?
The beef study was led by an international consortium of researchers known as NutriRECS, headed by Bradley C. Johnston, an epidemiologist at Dalhousie University in Canada. The Washington Post reported that NutriRECS had also formed a partnership with an arm of Texas A&M University partially funded by the beef industry.
“In April,” the Post reported, “Johnston announced the Agriculture and Life Sciences (AgriLife) program at Texas A&M would join the NutriRECS consortium and provide ‘generous support’ to NutriRECS. AgriLife includes a beef cattle teaching program, educational workshops for cattle ranchers, and promotion of Texas beef to consumers.”
In addition, another study author received funding from a Brazilian firm that is the largest meat-processing firm in the world.
A spokesman for AgriLife said its financial support for the study represented only a small fraction of its overall funding and suggested that “[y]ou might also look at the intellectual and financial conflicts of our adversaries.”
So what do you do?
As NBC News reported, the beef study’s conclusion “has been massively refuted by other health authorities and organizations, including the Harvard School of Public Health and the American Institute for Cancer Research.” In addition, studies consistently link reduced consumption of red meat and increased intake of fruits and vegetables—such as the dietary pattern found with the Mediterranean Diet—to a decreased incidence of CVD and certain cancers.
Our recommendation is that you would do best to limit red meat consumption to one or two servings a week if possible, and focus your overall diet on such natural foods as fruits, nuts, and vegetables, along with seafood and poultry. If you have any nutrition questions, be sure to let us know. We will provide the best advice we can base on established science.