If it sounds too good to be true, it usually is.

You might have encountered celery juice in the past couple months.

It started to pop up in juice shops, gourmet delis, and high-end grocery stores.

Anywhere that people could reasonably be expected to pay seven bucks for a drink that contains no alcohol.

In fact, it doesn't contain anything, but the juice that results from putting fresh stalks of celery through a juice press.

For this phenomenon, you have Instagram to thank.

As a journalist, I've covered lots of products and ideas that have become popular because of Instagram, but celery juice might be the one most disconnected from reality.

Many of these trends are pushed by influencers who have huge followings as a result of their perceived authority on health and wellness.

Some of these influencers have nutritional training and real expertise, but many don't.

Sometimes they're just good-looking former reality stars with a huge audience to monetize.

Whatever the case, they take great pictures and talk a good game, but there are few mechanisms on the platform to mediate misinformation.

As a trend becomes viral, claims about a food or products benefits lose their context.

And people who encounter it down the line might assume they come from some sort of authority.

That's usually not the case.

If you take the Instagram wellness community's word for it, celery juice can fight inflammation, regulate the microbes in your gut, remove toxins from your bloodstream and cure chronic illnesses.

Those claims have not only gotten it into stores across America, but also Gwyneth Paltrow's Goop website, Vogue.com, Good Morning America, and the Today Show.

Except according to every actual medical expert I talked to, none of those claims are true.

Celery is almost all water and relatively low in nutrients, so the best its juice can do is keep you hydrated.

When I looked into celery juice's origins as a trend, most people who had tried it assumed that doctors or medical professionals had recommended it at some point.

But as I trace back the sequences of people who celebrities, influencers, and regular Instagram users credited for their love of celery juice, it all led back to one man.

Anthony William, a middle-aged Florida guru who, under the name "Medical Medium," has more than a million Instagram followers.

The name "Medical Medium" might make William sound credentialed, but the legal disclaimer on his website is careful to explain that he is not.

Instead, Anthony claims to have been in contact with spirits since childhood, which grants him insights into health beyond what science can prove.

For most people, there's relatively little danger in trying one of these Instagram health fads, which recently have included Himalayan pink salt and glasses meant to protect your eyes from the glare of your phone.

But for those desperate to find affordable alternatives to traditional care for real ailments, these trends can be a harmful distraction from pursuing care that actually works.

And throwing away money on juice machines, for example, can make affording care even harder.

Remember that the next time a smiling face on Instagram tells you to try something new.