Randomized double-blind clinical trials (RCTs) are usually labeled the “gold standard” of medical evidence. But any given clinical trial can be done in an infinite number of ways. The length and duration of the RCT can vary. The eligibility requirements can vary. The definition of the placebo or comparison treatment can vary.
So on the broad issue of whether red meat is good for the heart, an RCT that compares the heart effects of red meat versus the heart effects of chicken, can yield different results than an RCT that compares the heart effects of red meat versus the heart effects of a plant-based diet.
Both RCTs might be competently done, involving no dishonesty or fraud.
We tend to overgeneralize the results of an RCT, for instance saying “red meat is heart healthy,” or “red meat is not heart healthy.” Whereas all we are justified in saying is “red meat is equally heart healthy as chicken” and “read meat is less heart healthy than a plant-based diet.”
Since RCTs are expensive and time-consuming, physicians and patients will often have to choose between treatments where no RCT has been done where the researchers made the choices that are most relevant to the patient’s situation.
And in an environment where RCT costs are high and funding is scarce, are researchers to be condemned if among the myriad varying ways of setting up the RCT, they choose the ways most likely to yield the results that will be appealing to their funder?
The article quoted below, in passages I did not quote, assumes this is only an issue with industry-funded research. But government funding review panels also have preferred outcomes. For example, Charles Piller in Doctored has recently documented that government funders have been more likely to fund RCTs that support the amyloid hypothesis of the cause of Alzheimer’s.
So is there hope for those who want to take effective action against dire disease? Yes, we can recognize that not all sound actionable evidence comes from RCTs. We can stop mandating Phase 3 trials, so that a more diverse assortment of plausible therapies can be explored. We can encourage diverse, decentralized funding sources.
(p. D6) In a review published last week in the American Journal of Clinical Nutrition, scientists came to a concerning conclusion. Red meat appeared healthier in studies that were funded by the red meat industry.
. . .
Past research funded by the sugar industry, for instance, has downplayed the relationship between sugar and health conditions like obesity and heart disease. And studies funded by the alcohol industry have suggested that moderate drinking could be part of a healthy diet.
Miguel López Moreno, a researcher at Francisco de Vitoria University in Spain who led the new analysis, said in an email that he wanted to know if similar issues were happening with the research on unprocessed red meat.
. . .
Dr. Moreno and his colleagues found that the trials with funding from the red meat industry were nearly four times as likely to report favorable or neutral cardiovascular results after eating unprocessed red meat when compared with the studies with no such links.
. . .
These differing results may have stemmed from how the studies were set up in the first place, Dr. Tobias wrote in an editorial for the American Journal of Clinical Nutrition that accompanied the new study.
Individual nutrition studies can be good at showing how the health effects of certain foods compare with those of other specific foods. But to demonstrate whether a particular food, or food group like red meat, is good or bad for health in general, scientists must look at the results from many different studies that compare it to all possible food groups and diets.
The new review showed that, on the whole, the industry-funded red meat studies neglected to compare red meat to the full range of foods people might eat — including food we know to be good for the heart like whole grains or plant-based protein sources such as tofu, nuts or legumes. Instead, many of the studies compared unprocessed red meat to other types of animal protein like chicken or fish, or to carbohydrates like bagels, pasta or rice.
The independently funded studies, on the other hand, compared red meat to “the full spectrum” of different diets — including other types of meat, whole grains and heart-healthy plant foods like soy products, nuts and beans — Dr. Tobias said. This more comprehensive look offers a fuller picture of red meat’s risks or benefits, she said.
. . .
A spokeswoman for the National Cattlemen’s Beef Association said in an email that “beef farmers and ranchers support gold standard scientific research,” and that both animal and plant sources of protein can be part of a heart-healthy diet.
For the full story see:
Caroline Hopkins Legaspi. “Eyes on the Outcomes Of Red Meat Research.” The New York Times (Tues., May 27, 2025): D6.
(Note: ellipses added.)
(Note: the online version of the story has the date May 20, 2025, and has the title “Is Red Meat Bad for Your Heart? It May Depend on Who Funded the Study.”)
The academic article co-authored by Moreno and mentioned above is:
López-Moreno, Miguel, Ujué Fresán, Carlos Marchena-Giráldez, Gabriele Bertotti, and Alberto Roldán-Ruiz. “Industry Study Sponsorship and Conflicts of Interest on the Effect of Unprocessed Red Meat on Cardiovascular Disease Risk: A Systematic Review of Clinical Trials.” The American Journal of Clinical Nutrition 121, no. 6 (June 2025): 1246-57.
Some other articles discussing cases where industry funding is alleged to have funded biased research are:
Anahad O’Connor. “Sugar Backers Paid to Shift Blame to Fat.” The New York Times (Tues., Sept. 13, 2016): A1 & ?.
(Note: the online version of the story has the date Sept. 12, 2016, and has the title “How the Sugar Industry Shifted Blame to Fat.”)
Alice Callahan. “Is Fake Meat Superior to the Real Thing?” The New York Times (Tues., Feb. 18, 2025): D7.
(Note: the online version of the story has the date Feb. 17, 2025, and has the title “Is Fake Meat Better for You Than Real Meat?”)
Roni Caryn Rabin. “U.S. Wooed Alcohol Industry for a Drinking Study.” The New York Times, First Section (Sun., March 18, 2018): 1 & ??.
(Note: the online version of the story has the date March 17, 2018, and has the title “Federal Agency Courted Alcohol Industry to Fund Study on Benefits of Moderate Drinking.”)
