Zooey Deschanel has a Facebook page where she gives advice on complex scientific topics. I love Deschanel as an actress and enjoy much of her work (particularly the otherwise mediocre movie version of the Hitchhiker’s Guide), but that does not mean I want to take advice from her on which foods I should eat.

Celebrity culture, in one form or another, has always been part of human society. Even chimpanzees will follow a charismatic leader, and it seems likely that humans are wired also to follow those we admire, and elevate them perhaps a bit too much. There is even research that shows that when we listen to a charismatic speaker the executive function part of our frontal lobes shuts down. We literally turn off our critical thinking when basking in the glow of our glorious leader.

Recognizing that this is part of the human condition is important. First, we need to be vigilant about surrendering our thinking to others. It’s also important to remind ourselves that everyone is a flawed human, and so constantly give those pedestals a reality check.

But that does not mean we should not admire and respect those who deserve it, or even look up to them for wisdom (as long as we maintain our critical eye). It does mean we need to choose carefully those we respect and follow.

Many people have written recently about the death of expertise. This is a concerning trend of lessening respect for those with genuine expertise, earned through years of study and experience, and often evaluated in some formal way. This may just be a historical trend swinging back and forth, and we happen to be going through a period of populist rejection of  authority. Regardless of cause, it is a dangerous trend. We live in an extremely complex technological civilization. Our lives literally depend on countless experts doing jobs we do not understand (or may not even know that they exist). It’s hard to know exactly how fragile the whole system is, but I don’t really want to find out.

But here is another point – while populists congratulate themselves for being independent thinkers and rejecting the authority of experts, they aren’t really. They are just replacing one set of authority figures for another. In many cases celebrity culture is stepping in to fill the void, and the result is not likely to be good.

In a recent commentary on the phenomenon, Michael Schulson points out:

As many celebrities have discovered, the combination of wellness culture, ethical consumerism, and Hollywood glamor can make for a potent — and profitable — media cocktail. Pioneers of the model include Gwyneth Paltrow’s Goop, a health and lifestyle brand, Jessica Alba’s Honest Company, and even Tom Brady’s TB12.

Exactly. I would add that sometimes health gurus become celebrities (Dr. Oz), and sometimes celebrities become health gurus, but the end result is usually the same. Paltrow’s Goop is probably the most successful example at this point, but there have been and will be others.

The very fact that Oprah’s name was seriously floated as a potential presidential candidate indicates how pervasive celebrity culture is. (I have already dealt with this nonsense.)

Spend any amount of time having discussions with those who follow any anti-science echochamber, an ideological belief, or a celebrity guru and you will see that they simultaneously rail against bowing to the authority of academics or scientists, as they are bowing to the authority of their guru or group.

We often make fun of those who claim they have “done their research” because what they really mean is that they have read a bunch of biased and cherry picked articles by hacks dedicated to an anti-scientific agenda.

Getting back to Deschanel – in one of her videos she literally advises people who are too poor to buy all organic to not eat certain vegetables, such as apples, tomatoes, grapes, peppers, and potatoes, because they may contain pesticides. This is a perfect example of how following fear and pseudoscience often leads to the exact opposite of what you want to achieve.

First, there is no evidence that eating fruits and vegetables poses any health risk due to pesticides. Residues are carefully regulated to be far below safety limits. Further, if you want to give yourself even more of a buffer of safety, then just wash your produce thoroughly.

Also, people on a limited budget tend to have worse diets, with real health consequences. Scaring them into avoiding cheap and abundant vegetables is really counterproductive. It also is a manifestation of privileged residents of industrialized nations imposing their nonsense on those with less privilege and causing harm. They have the luxury of wasting money on boutique food to make themselves feel better, but they should stop interfering with those for whom a healthful diet is not a given.

It also has to be pointed out that organic farming can and often does use pesticides. For marketing, they mostly use pesticides they can sell as “natural” – but they are usually more toxic than conventional pesticides, and have to be applied in larger amounts and more often. This is because they are not using the best pesticide, but ones that feel “natural” even if they are worse.

But Deschanel, steeped in Hollywood culture, and without any relevant actual expertise, is now perpetuating these marketing myths based on fear, and is giving bad advice. She is actually telling poor people to avoid certain vegetables in their diet, or waste money they really can’t afford on the worthless organic label.

I don’t mind if celebrities lend their fame to a cause, or give voice to a science documentary. That’s all good. But they should not confuse their celebrity with expertise, or wisdom, or really anything else. More importantly, the public should not make this mistake. I do think it is probably good advice to separate the art from the artists. Famous actors are good at acting, and I will enjoy their art – but I really don’t care about their opinions on science or health topics, or even their political opinions. If they want to be taken seriously on a topic other than acting, they will need to earn that right separate from their celebrity.

And in general – maintain a healthy skepticism toward any authority, and choose your authority figures wisely. Specifically, fame and even charisma should probably not even be criteria.