I stood in line at the grocery store waiting to pay for my items. The woman behind me, who would be categorized as obese, was eyeing some of the snacks so conveniently placed in the checkout aisle. She grabbed a meal bar and analyzed it for a few seconds, then said aloud to me: “You ever had one of these? They’re pretty good. And they’re gluten-free, that’s how you know they’re healthy.”

Healthy.

What a word. A trillion different opinions, guidelines, historical changes, and bits of data crammed into seven letters. A word we toss around like a hot potato, assigning to it whichever meaning is most convenient or profitable. A word that has become, essentially, meaningless.

Need convincing?

This headline was published in Healthline. How are they categorizing “super healthy?” Doesn’t matter, just know that these 50 foods are.

Or what about this one by Fitness Magazine? The “proven” foods include potatoes, beans, dark chocolate, and broccoli. Are they “healthy?” Who’s to say? No, seriously — what research are they using and who is saying that the foods on this list are proven to facilitate health? Proven?

This one by EatingWell cites seven of the healthiest foods. It shares almost none with the ten healthiest foods from the previous list, unfortunately (you’d hope a consensus would develop). This one praises oatmeal, pomegranates, and quinoa. The subtitle asks if you’re getting enough of them. Well, how much is enough? Should we all fill our bathtubs with oatmeal and eat until we’re incapable of movement? You might say well obviously not — but why is that obvious? If we regress many steps and analyze where this information comes from, it becomes difficult to identify a source.

I’d like to stop here, but I suggest looking up “healthiest foods” and perusing for a bit. Or healthiest exercise, healthiest products, healthiest anything. The concept of “healthy” is undefinable so the ability for something to be that is limitless. The infinite results explain my experience in the grocery store checkout line. They explain how someone who arguably does not feel healthy (this is a generalization, as obesity and infirmity are not always correlated) could so confidently claim, “They’re gluten-free, that’s how you know they’re healthy.”

The confusion comes from marketing. Strategic, wonderfully executed marketing. But we cannot demonize corporations, as they are doing exactly what they should be doing. They have a product and are brilliant about selling it. They show nature-filled commercials with a friendly narrator who praises the energy-boosting properties of their chocolate sugar bar. But perhaps these corporations and the industry they represent are a little too brilliant. They know information sounds untrustworthy when it comes from them because they have a product to sell — so what do they do? Pay researchers at respected institutions to publish information in which the corporations can then market.

I sound like a conspiracy theorist, so take this meta-analysis for example. It analyzes trials that question the link between sugary beverages and metabolic outcomes like obesity and diabetes. Here’s what they found. Twenty-five of the twenty-six papers that maintained sugary beverages and metabolic outcomes were not related were funded by the sugar industry. Contrarily, one of the thirty-four papers that concluded sugary beverages arerelated to obesity and diabetes were funded by the sugar industry. The results of each study were almost entirely dependent on who paid the researchers. In a letter to the Annals of Internal Medicine, Schillinger et al conclude: “This industry seems to be manipulating contemporary scientific processes to create controversy and advance their business interests at the expense of the public’s health.”

Confounding the issue of problematic research are the publications which report on them (see above for Healthline, Fitness Magazine, and EatingWell, to name a few). These are profitable companies with advertisers, so they are fueled by page visits. Sensational headlines — especially about health — garner page visits. Authors for these sites write health information that could be categorized as opinion, embedding links to research that is either itself faulty or that does not say what they say it says. (The authors assume, often correctly, that a reader is not going to follow the link to an empirical study). Then, different blog sites take the misinformation from this site and report on it, creating an environment where outlets are citing each other on information that was initially misinterpreted. This is the system that allows us to so confidently claim something is “healthy.”

In another meta-analysis, this team of researchers conclude less than 16% of information found online is scientifically sound. Did you click on the embedded link or are you inclined to continue reading, ready to tell the next person you see about the 16% concept? Click the link. Maybe there is a study behind the claim, or maybe it sends you to an entertaining John Oliver segment about research. My point: See how easy that was?

Demonizing corporate interests (or quirky blog posts) is misplaced blame. The problem lies in the integrity of research institutions. It is a privilege to work to advance scientific knowledge, to teach medical students, and to write advice or guidelines for public health. Those who are privileged enough to be in this roles should not — under any circumstances — take private industry funding. But this is the norm.

The sugar industry is the tip of the tip of the iceberg. Nutrition is largely excluded from medical education anyway: We in medicine tend to be as clueless as anyone about useful dietary advice. More harmful to the integrity of the medical institution are the effects of private funding from pharmaceutical companies.

We as medical students learn the usages and side effects of pharmaceutical therapies. We learn which drugs should be prescribed for which diseases, and we trust those who teach us to have scientifically supported and unbiased knowledge. What other choice do we have? Medicine is a foreign territory for medical students — we retain what we learn from those who navigated the world before us. It would take massive amounts of extracurricular dedication to question the material we learn, and for what? Our success is determined by the scores we achieve on exams, which is regurgitating what we have been told.

Historically, information taught to medical students can be wrong, later being disproven and reversed. There is a saying that goes from educator to student which encompasses the ever-changing nature of medical knowledge: “50% of what we teach you over the next 5 years will be wrong. Sadly, we don’t know which 50%.” Topics range from using heroin and bloodletting as therapeutic treatments in the 19th century; to hormone replacement therapy for pregnant women in the 1990s; to statins and insulin now.

What medical students are taught can also be biased: the same physician-researchers who take money from food or drug companies find themselves at the front of lecture halls. This is not a coincidence: They gain prestige from speaking at pharmaceutical company gatherings — invitations they received from doing industry-funded research — then they become an “expert,” which helps them be hired or promoted as faculty at a university. It’s a revolving door.

The consequence of shady research is that it puts into question thorough, legitimate research — which is a pillar of science, progress, and knowledge. Research with integrity is at the foundation of everything we know. When we allow corporate interests to infiltrate this foundation in any way, trust in the entire realm collapses. This means pseudoscientific health claims — which are nonsense at best and harmful at worst — can capitalize on the vacuum of scientific certainty, claiming absurdities while citing that scientific evidence is untrustworthy in its entirety.

We in medicine must be vigilant about information. It is absurd that medicine not only accepts, but normalizes,  industry funding in research, regulations, and guidelines. This aspect of health knowledge cannot be ignored.

What can we do? Perk up with skepticism when someone claims something to be healthy. Click on links and read through the academic papers that are cited. Find out who funded circulating research. Question information, even if it comes from those who are standing at the front of your lecture hall. If you find yourself in a research position, refuse to be a pawn for companies with an agenda. We in medicine have a duty to promote health, but until private interests are eradicated from influencing our knowledge that duty will be difficult to uphold. We owe it to our current and future patients to try.

Jamie Katuna is a medical student.  She can be reached at her self-titled site, Jamie Katuna, and on Facebook.

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