The Scientist: Gina Sam, MD/MPH, Director of Mount Sinai Gastrointestinal Motility Center, Assistant Professor of Medicine, Attending Gastroenterologist

The Answer: Waist training corsets, also called waist trainers, are popular with celebs right now for putting external force on the body to create the coveted “hourglass figure.” Waist trainers do this by putting pressure on your stomach and intestines. Side effects of a too-tight corset range from heartburn and abdominal pain or pressure to colon discomfort and discomfort in the lower abdomen. If you’re wearing a waist training corset for just one evening, you may feel fine – but remember that your body goes right back to normal once you remove the garment.

A waist trainer is meant to be worn short-term. There’s no medical data yet on the safest length of time to keep one on, but don’t believe celebrities’ hype that makes it seem like they spend all day, every day in a colon-pinching corset. Celebrities may walk the red carpet with a corset on under a gown for one evening, but there’s no medical evidence to suggest hitting the gym while wearing a waist trainer (a la Kourtney Kardashian) will help you lose weight faster or shape yourself into an hourglass figure.

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If you feel heartburn or pressure, your waist trainer is too tight and you should remove it immediately. Cinch too tight, and you could even break a rib! Keep tabs on your body to be sure that you’re comfortable at all times. (Accurate bust-waist-hip measures will help you find the right size for you.)

Key takeaways: The name “waist trainer” itself is misleading, as you won’t be losing any weight or “training”/permanently changing your body by wearing one. Overall, if you’re looking to alter your figure, there’s no substitute for plain old diet and exercise.

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