When it comes to nutrition, we’re used to moving targets. Eggs are good, then bad, then good again. First fat was the enemy, now it’s sugar. This week’s superfood is kale, next week’s will be blueberries. Yet with all of the uncertainty, red and processed meats was something that we thought we had down. Then came a new study this past week in the Annals of Internal Medicine, widely reported on with a collective gasp, claiming that maybe these meats aren’t so bad after all and that we should probably go ahead and keep eating them. Ready to throw your hands up and binge on everything you’ve ever desired? Read this first.
It’s Time To Talk About Evidence
In one of the follow up articles to the story printed in the New York Times, a very important quote appeared. Speaking on nutrition guidelines at large, Dr. Dennis Bier of Baylor University said this:
“[Nutrition] guidelines are based on papers that presumably say there is evidence for what they say. And there isn’t. That’s the history of nutrition.”
This statement sounds extreme at first glance, but it is not. The thing about nutrition science is that it usually relies on observational evidence and, as we all know, observational evidence is tricky because looks can be deceiving. If you look out the window on a rainy day, for example, and see everyone has an umbrella, you might conclude that umbrellas cause rain. That’s obviously wrong, but if you were an alien from another planet how would you know? You’d need to do a controlled experiment to test your observation, like having people take umbrellas out on a sunny day to see if it changes the forecast. Now, here’s the rub: because observational data can be misleading, other fields of science such as physics or chemistry consider it to be weak evidence. You can’t get away with saying the earth is bigger than the sun just because that’s how it looks from the ground. You need harder, less subjective evidence.
As far as that point goes, the new research seems to be correct in the assertion that the evidence for reducing our consumption of red and processed meat is not, at least by the standards that we hold other scientific disciplines to, particularly strong. That being said, the research has drawn some deserved ire because it takes that point as a justification to suggest that we all go ahead and continue eating these products just as much as we currently are. In other words, they are committing the same sin in a different form. Weak evidence that something is harmful does not constitute strong evidence that it’s ok. We do in fact have reason to suspect that these meats might be unhealthy. We just need to remember that, like in the criminal justice system, suspicion doesn’t count as evidence.
Now Let’s Talk About Bias
After the initial report on this study and the ensuing outrage another follow up article in the New York Times disclosed, again with a gasp, that the lead author on this study had ties to the food industry. He hadn’t reported them, he says in the article, because the journal only asked about relationships within the past three years and these ties are more than three years old. It’s a squint-worthy excuse, maybe even side-eye worthy. However, when asked about it Dr. Christine Laine, the editor in chief of the Annals of Internal Medicine, had something very interesting to say on the subject:
“Many of the people who are criticizing these articles have lots of conflicts of interest they aren’t talking about,” she said. “They do workshops on plant-based diets, do retreats on wellness and write books on plant based diets. There are conflicts on both sides.”
When it comes to health and fitness, this is a point that is worth reflecting on. As a society, we’ve become much more aware of the kind of bias that is baked into the medical industry, like the fact that surgeons tend to recommend surgery, that specialists tend to think all your ailments are related to their specialty, that dentists sometimes go hog-wild on fillings, etc. It’s the old if-you-are-a-hammer-everything-looks-like-a-nail problem. The same is true with health and fitness. Pilates instructors recommend pilates. Strength trainers recommend strength training. Yogis swear by yoga. And yes, vegans recommend veganism, vegetarians recommend vegetarianism, paleo people recommend paleoism (a new word!), and on it goes. The important point is that often, these recommendations are not because the evidence is so overwhelmingly confirming, it’s because the practitioner is deeply sold on it. That doesn’t necessarily mean the recommendations are bad ones, but it does mean that claims about the evidence should be received skeptically.
Gather Information, But Evaluate It Yourself
So where does that leave someone who just wants to know whether or not they should eat red meat?! Well, it certainly isn’t easy. As far as understanding the evidence goes, in any health and wellness question, the best practice is to research widely and then evaluate for yourself. If you are looking for something a little less time intensive, a good rule of thumb in fitness—probably in life as well—is to greet extremes with suspicion. It might not be necessary to avoid all red and processed meats, but that’s not a license to eat it with no limits either. At least in fitness, when faced with an unclear choice, the middle road usually serves you well.