My social media feeds me a lot of health-related content. A common format is a video of someone spouting all kinds of medical falsehoods, and then a real doctor explaining why it’s wrong. And as I watched one tonight, I thought to myself, “no one is going to believe him—he’s just a doctor, not a real expert.”

Boom. That hurts. My own brain has betrayed me.

Social media, like all propaganda, can change the way we think. It’s a part of the current cultural movement to de-legitimize expertise and to value clicks and hot takes over facts. This is not a new human behavior, but our current media environment certainly magnifies it.

(If you’ve never played “Plague, Inc.”, it’s a video game that lets you create and spread a disease with the objective of wiping out all life on Earth. You get to choose what kind of germ to use and you can alter factors such as whether it is airborne, causes diarrhea, has visible symptoms, etc. Capturing the zeitgeist, they’ve added a new virulence factor: ”fake news”.)

So what is a medical expert? Am I one? Are there limits to my expertise?

A common misstep we often make is that when we are an expert in a particular field, we somehow are experts in other fields as well. A famous example is Linus Pauling, the Nobel Prize-winning chemist who decided he was an expert on the effects of vitamin C on health—and got it all wrong.

Part of being a real expert is knowing the limits of your expertise. What makes me an expert in internal medicine? To become a specialist in internal medicine, I completed an undergraduate bachelor’s degree, a four year medical doctorate, and three additional years of residency training. It’s a long, rigorous road to take, and not everyone who walks it becomes, in my opinion, an expert. The difference between a doctor who is an expert and one who isn’t is usually a matter of not caring as much about keeping up with the science, or, as Linus Pauling did, forgetting the limits of your knowledge. Patients often ask me about, for example, the back surgery they are planning, and I am careful about saying more than I know—it’s not my field.

Why do people trust random folks on the internet more than doctors, even their own? It’s complicated. A lot of it has to do with how we are wired to think, and a lot more with the current social and political climate. We don’t naturally rate people based on their true expertise, but rather whether they are part of our “tribe” or say things that fit our beliefs. This is why simply educating people about the truth often fails.

It’s very hard for me to watch friends, family, and patients absorb all the medical falsehoods floating around out there. Because of the way the human mind works, someone can trust me to take care of their diabetes, blood pressure, and heart disease, but think I’m somehow totally wrong about, say, flu vaccines. So while simply giving facts to people doesn’t often work in countering these messages, giving them tools of skepticism can really help. Let’s take cholesterol medicines as an example.

The evidence of the importance of cholesterol medications is solid, as is the safety data. One of the most dramatic findings is that among people recently hospitalized for heart disease, those prescribed statin therapy had a 65% lower risk of death over the following year. I’ll post a piece at some point digging a bit deeper but suffice to say there are very good reasons for your primary care doctor or cardiologist to recommend a statin medication in the right situation.

Despite forty years of safety and efficacy data, many people decline to take statins, even if they are at high risk for heart attack. It’s important to give them the facts and try to save their lives, but that’s only a part of helping them. It’s important to personalize it—I take a statin, my wife takes one, most doctors who need them take them. It’s also important to ask where their information comes from—respectfully. What is the motive of the guy on Instagram/Facebook/TikTok who tells you statins are trash? Clicks make money. And the dude on the internet has no ethical obligation to you. He doesn’t know you. He knows monetization of page views.

Your doctor (and yours truly) doesn’t get paid to prescribe statins. No one is making a ton of money on them, and they only cost the consumer a few bucks a month. But most important, your doctor’s ethical and moral obligation is to your health, not their own benefit. If you take a second look at all the people online posting videos about the dangers of this, that, or the other proven treatments, you’ll see an entertainer making a buck (and I don’t begrudge them their income, unless they are a professional who should know better). If someone is giving advice that goes against the consensus of medical science, ask yourself, “what’s in it for them?” I can tell you what’s in it for me—the health of my patients.

People being people, we will all fall for information that is provably false—news, politics, science, medicine—no topic and no person is off limits. But we can adopt both an open-minded and a skeptical mindset. We can ask if it truly makes sense. We can ask who benefits.

Expertise matters. That doesn’t mean blindly accepting all you hear. It means do the cognitive work of deciding whether a particular expert really is an expert, and whether they are to be trusted. It takes the hard work of setting our own biases aside to look at things as objectively as possible. And it’s worth the work because, at least in my line of work, lives are on the line.