It’s a thirst trap.

Dry-fasting, a fad diet gaining traction with Instagram lifestyle gurus, restricts water as well as food — and some people are taking it to dangerous lengths, experts say.

“I don’t drink any water, and haven’t done so since December 2016,” Alice Copilet, 36, tells The Post. “I eat my water via fruits, which contain high amounts of the best water, filtered by nature.”

Typically, dry-fasting calls for abstaining from both food and water for 16 to 36 hours at a time, but die-hard followers like Copilet are pooh-poohing humanity’s most vital resource and eliminating it from their lives entirely because they believe it actually doesn’t hydrate the body.

Instead, Copilet prefers to get her daily water intake through “fruits, veggies, herbs and coconuts” — and broadcasts her beliefs to her some 11,000 followers on Instagram and Facebook.

“This is what hydrates the body at a cellular level — not plain water, which merely acts a solvent, flushing acidity from the body but not actually hydrating the cells,” she writes in a post.

But experts disagree, and are disturbed by the trend.

“There’s a reason we feel thirsty, and it’s because the body is saying, ‘Oh, you need water.’ It’s a natural response,” says Sarah Miller, a registered dietitian at the Northwell Health Lipid Center in Great Neck, LI. “Depriving yourself of water is dangerous and puts you at serious risk of dehydration.”

While Miller admits it is possible to get some hydration by eating “tremendous amounts” of fruit, the amount of sugar and overloading on one food group can pose health risks, too.

“Too much sugar can lead to weight gain. If you’re diabetic, it could be dangerous, [and] if you eat sugar, sugar, sugar all day long and have an underlying predisposition to diabetes, you’re at a higher risk of developing it,” says Miller.

Kidney function is another point of contention between dry-fasters and medical experts.

Water shunners believe the liquid is tiring for kidneys, which can only process liquids or lymphatic fluids one at a time.

But Miller retorts, “Restricting fluids is actually more taxing and dangerous — water helps dilute all the other elements the kidneys filter.”

Influencers praising the diet are also citing personal experiences — rather than strictly medical proof and facts — to extol the virtues of going water free.

“Skepticism is very natural, and it has its benefits, but nothing trumps direct experience,” Copilet insists. “My body made it very clear to me that dry-fasting was incredibly beneficial.”

Five years ago, Copilet was working as a corporate lawyer in London and never dreamed up giving up her meat, dairy and water-drinking habits.

“I had a successful job, really cool, successful friends, [a] thriving social life, handsome boyfriends, et cetera . . . But I wasn’t happy,” says the self-proclaimed “fruitarian” who now lives in Koh Phangan, Thailand.

She set out on a journey to self-discovery, which led her to “Quantum Eating: The Ultimate Elixir of Youth” by Tonya Zavasta. The book inspired her to try dry-fasting, and she’s never looked back.

Today, she works as a yoga teacher and fasting coach, and has inspired others to follow in her footsteps, such as Sophie Prana.

Several years ago, Prana, 35, was battling with health problems including a puffy face and digestion issues. Doctors told her nothing was wrong, but, desperate for answers, she decided to listen to Copilet’s advice, whom she met in southeast Asia, and do a 36-hour dry fast.

“I felt change immediately,” says Prana. “The swelling went down. Something changed with my digestion. And then I started to, like, look into this whole thing of living on fruits and raw food.”

Amazed, she gave up water for good.

“My family freaked out and thought I’m in a cult,” added Prana, who’s based in Vienna and has been water free for a year. “Everybody thought, ‘Oh, now she’s completely lost it.’ ”

She’s now a wellness influencer, colonic hydrotherapist and yoga teacher with 18,000 Instagram followers.

But Miller says to be wary of the so-called success stories on social media: Condoning this diet is anything but healthy.

“It’s irresponsible to encourage others to do this,” she scolds. “My initial response is: Please just no.”