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On a recent Wednesday afternoon, the Whole Foods in Williamsburg, Brooklyn, was absolutely bereft of celery.

Conventional, organic, whatever—Hilary Sloan was out of luck. Sloan, a former colleague of mine who works in marketing, was looking for celery because a friend had evangelized to her about the health-promoting properties of celery juice. That friend had learned about the juice’s magic in the well-trafficked wellness corners of Instagram.

The claims circulating about the juice are indeed enticing: Depending on whom you talk to, it promises to relieve inflammation, improve your microbiome, alkalize the body, kill mold in your gut, cure chronic mystery illnesses, and banish “toxins.” Suddenly, everyone from Vogue to Good Morning America recommends you give it a try.

For wellness-focused businesses, celery juice’s exploding popularity has been impressive and sudden. Zach Berman, a co-founder of the popular Vancouver-based juice business The Juice Truck, told me his company added the drink to its official menu two weeks ago as a result of overwhelming consumer demand. “This has been the most interest in a cold-pressed juice since green juice originally became popular, in 2011,” he says.

The American chain Pressed Juicery also added bottled celery juice to its menu a few months ago. When I recently asked the cashier at one of its New York locations if it had been popular, her eyes widened. “Yes. Extremely,” she said. I was there to try celery juice for myself. It cost $6.50 and tasted like celery. I don’t know what I was expecting.

Sloan, for her part, wasn’t expecting much, but was also hoping she was wrong. “It could help rebuild my immune system, which is terrible right now,” she says. “At the very least, I’ll be more hydrated.” After an accident last winter, she has had five surgeries and been on months of antibiotics, and although skeptical about the promised benefits, she felt open-minded about trying something that seemed, at worst, totally innocuous.

And that’s just the mix of emotions and circumstances that can make nutritional trends so tempting—and that medical-adjacent gurus might capitalize on. As strange as “Celery juice is a miraculous health elixir” sounds, the way it’s become a burgeoning trend might be even stranger.

Anthony William calls himself the “Medical Medium.” He has 1 million Instagram followers and the affection of the kingmaking wellness website Goop, which has published him expounding at length on the topic of celery juice. By his description, the upsides of drinking the juice daily (always by itself, always first thing in the morning, always before eating or drinking anything else) border on the magical. William lacks any sort of medical or scientific training or certification, according to the legal disclaimers on his website and his Goop contributions, but he claims a spirit he’s been in contact with since childhood has given him knowledge of health and wellness beyond what science can confirm.

No matter whose interest in celery juice I try to trace back to its source, it always ends up with William, and in his writings, he also claims to be the trend’s originator.

William did not return my requests for comment, and he seems not to engage frequently with traditional press. He’s written three books and has built a considerable following across social-media platforms and his own website, where he offers paid phone consultations to sick followers for hundreds of dollars apiece, according to the journalist Rae Paoletta. In addition to that, he uses revenue-generating Amazon affiliate links extensively, including to 177 nutritional supplements and additives he recommends.

The Medical Medium website also features testimonials from A-list celebrities such as Robert De Niro and Naomi Campbell. I wasn’t able to independently confirm these specific endorsements, but there’s no question William has his admirers in Hollywood. Goop, which has significantly raised William’s profile, is owned by the actor Gwyneth Paltrow. A reporter for InStyle heard the actors Debra Messing and Allison Janney discussing their adherence to William’s celery-juice regimen at a party in August. They also follow him on Instagram.

On a platform like Instagram, where there are few forces mediating the information that’s passed from a celebrity or influencer to her followers, it’s notoriously easy for health information of questionable veracity to spread like a game of telephone—losing attribution and context as it moves. When I mentioned to Sloan that William appeared to be the trend’s originator and that his background was questionable, she was surprised. “He’s not a doctor?” she asked. She’s only been on celery juice for five days, but she says she feels pretty good—at least, more hydrated.

I asked the registered dietitian Ashley Koff what she thought of celery juice, and she wasn’t impressed, even though she was enthusiastic about celery as a healthy snack in general. “There is no one food that will cure your cancer, inflammatory disease, or other ailment, so don’t believe the hype you see and hear on Instagram,” she said. That was echoed by Lisa Young, a registered dietitian, nutritionist, and professor of nutrition at New York University. “You’ll see something take off where you just have to have celery, or you just have to have kale—one vegetable is really not better than another,” she said.

The nutritionist and author Kimberly Snyder, on the other hand, was more optimistic. She praised celery juice as hydrating, vitamin packed, and anti-inflammatory. She also pointed out that recent research showed celery seed as a helpful check on hypertension for people dealing with blood-pressure problems.

A recent study out of the Cleveland Clinic bears out celery’s blood-pressure benefits, but the researchers recommend consuming full stalks instead of extracts in order to get maximum benefits. Young, too, mentioned that maybe celery might be better intact, as a snack or as an addition to a meal rather than as a medicine. “You don’t have to drink it; you can also chew it,” she says. “Whatever happened to chewing?”

The celery juice I bought listed four vitamins. Of those, the most abundant was vitamin A, and the bottle promised 30 percent of what the average person should have in a given day. As far as hydration goes, most of celery juice’s proponents cite solid celery’s 95 percent water composition as a way of proving the juiced version’s promise. Regular water is 100 percent water. I drink a bunch of that every day anyway.

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