Chrissy Teigen admits to using a waist trainer. How safe is it?

Kim Kardashian West is probably the biggest waist-trainer advocate on the planet, but new mum Chrissy Teigen is now following in her good friend’s footsteps. After giving birth to her daughter, Luna, in April, the supermodel says she’s been using a waist trainer to whip her middle into shape.

Teigen just starred in Fergie’s “MILF$” video, looking as fab as ever — but she swears she’s got more work to do and that the waist trainer is helping her along the way. “I think people think that I’ve snapped back, but I really have just, in fact, been utilising undergarments more,” she tells People. “I never was a Spanx person or a waist-trainer person. Now I do it. It looks great on the outside, but trust me, I’m a bit soft.”

Waist trainers are seemingly always in the news for some reason, whether positive or negative, but how safe and effective are they? Especially for new mums? Gina Sam, MD, an assistant professor of gastroenterology at Mount Sinai Health System, wants to set the record straight about what these trendy body-shapers actually do.

“They’re similar to a corset, where they restrict the waist,” Sam tells Yahoo Beauty, explaining that most women “do just fine” with a little extra support around the middle. “Some claim you will lose body fat while using a waist-trainer, and that is not true. There is no research to support that.”

Some experts, like Ruben Soto, CEO of HourglassAngel.com, say that the waist trainer does carry multiple benefits, including some weight loss potential. “Results vary from person to person, but waist training has several benefits,” Soto says. “You get an instant hourglass shape the second you put it on. It’s also a great complement for a healthy lifestyle that can help you feel confident and keep you motivated with your diet and fitness.” He also says that many waist trainers “stimulate thermal activity in your core, so you sweat harder during runs, workouts and other exercises.” This could theoretically allow you to burn more calories.

Sam and Soto both say that the waist trainer is not a replacement for healthy diet and exercise, though — and Sam thinks waist trainers are becoming prevalent enough for scientists to put those weight loss and fat loss claims to the test, by way of a randomised controlled clinical trial. Until then, however, she says to consider these undergarments in the realm of supertight Spanx.

The negative side effects are minimal, and mostly relate to wearing a waist-trainer that’s too tight — think shortness of breath, abdominal pain, even bruising. “You are binding the organs in there, putting pressure on the lungs, stomach, small intestine, and colon,” Sam explains. “So it’s not uncommon to see those issues.” Of course, if you’re experiencing any of those symptoms, it’s time to loosen your waist trainer or take it off.

Bottom line: Think of Teigen and Kardashian’s tiny-waist mechanisms as a temporary fix, similar to Spanx. “Many use it for support, and that is fine,” Sam says. “But it won’t help you lose body fat, no matter what claims are out there. The research doesn’t back it up.”

People have mixed emotions about waist trainers, and you shouldn’t expect fat loss. But if they make you feel better about your body, then go for it.

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