From Spanx Power Panties shorts, to Reebok CrossFit compression tops, Lululemon running tights for men and modern-made corsets, there is a huge market for clothes that squish, squeeze and sculpt. For some people, shimmying into shapewear is worth it for the figure-enhancing powers of Spandex, an attitude shared by Katy Perry, Kim Kardashian and Heidi Klum, who have given Spanx credit for making them look good on the red carpet. Others wear compression clothing to run faster, lift heavier weights or reduce soreness after intense exercise.
But, doctors warn, there are real health risks to wearing extra-tight clothing for prolonged periods. Instead of stuffing your body into suffocating clothes, some experts advise, it may be better to stick with more proven forms of body-shaping behavior. Plenty of people are taking the clothing way, however; research firms estimate that shapewear is a $680-million annual market.
"We all want a shortcut that will be more effortless," says Orly Avitzur, a neurologist in Tarrytown, N.Y., and medical advisor to Consumer Reports. "But that doesn't help us in terms of all the advantages of exercise and a really nutritious diet."
Neurologists have long known about a condition called meralgia paresthetica, which causes painful burning and tingling in the thighs when there is too much pressure on nerves that run through the groin. The condition is most common in pregnant women and people who gain weight quickly, as their pants suddenly become too tight. But every month or two, Avitzur says, she sees a patient suffering from nerve pain because of shapewear.
Some patients defy stereotypes, including a 15-year-old girl who came to her office after seeing a gastroenterologist for stomach pain.
It turned out that the girl's entire soccer team had been wearing colorful compression shorts under their uniforms at school, a fashion trend that was common among high school teams in the area. "I wouldn't have normally asked her if she wore tight compression clothing because she was a young athlete," she says. "It wasn't until I was almost leaving the room, and I said, 'In my mother's generation, we saw this in women who wore girdles.'"
Tough to digest
Putting pressure on the abdomen squeezes internal organs, which can push acid from the stomach into the esophagus. That's why weight gain can lead to gastroesophageal reflux disease, and tight undergarments can do the same thing, says Jay Kuemmerle, a gastroenterologist at Virginia Commonwealth University in Richmond. "It's really just plumbing," he says. "For someone who has reflux disease or is prone to reflux, wearing tight garments may exacerbate those symptoms." Tight clothes can also worsen the discomforts of irritable bowel syndrome and urinary incontinence, he says. As for the Jessica Alba-endorsed "corset diet," Kuemmerle doesn't recommend shapewear for weight loss.
More pain, less gain
Wiggling your limbs into shaping garments takes effort, and it is equally difficult — and perhaps not very sexy — to peel them off. Many women don't bother, avoiding the bathroom for as long as they're wearing their Spanx. But holding your bladder can lead to urinary tract infections, Avitzur says. Sweating in tight clothing can also cause yeast infections and skin irritation. People with diabetes are at particular risk of developing skin infections from snug clothes. Googling suggests other potential health dangers including varicose veins, blood clots, weak core muscles and back pain, though, according to some researchers, those risks are overblown. Doctors often prescribe compression stockings to improve blood flow and reduce the risk of clots after surgery or for people who have circulation problems. "I'm not trying to say that everyone wearing restrictive garments is going to have problems," Kuemmerle says, adding that most problems go away quickly when the clothing pressure is off. "But adopting a healthy lifestyle may obviate the need to feel like you have to wear these things."
Pressure to the finish line
Elite runners like Paula Radcliffe and Meb Keflezighi have helped popularize knee-high compression socks, which have become trendy among amateur athletes too, along with other tight workout clothing.
The idea is that squeezing muscles might improve circulation, eliminate waste products and increase power by reducing the amount of force muscles need to produce.
Evidence, however, is mixed, says Philip Skiba, director of sports medicine at Advocate Medical Group in Chicago. Research is also still new, as scientists have been conducting rigorous studies on compression gear for less than a decade. And most studies include only a dozen or two athletes, making it impossible to generalize results for everyone. Given the research so far, Skiba says, there is no convincing data that compression garments lower levels of lactic acid in the blood, reduce muscle damage or inflammation, or make people run, ski or kayak faster.
Compression garments may, however, offer some help with recovery after hard exercise.
In a 2014 study of 24 runners, athletes who wore compression socks after completing a marathon reported less soreness 24 hours later. For sprinters, studies suggest that wearing compression socks for a few days after a workout could help them go a few seconds faster during their next several-mile-long run.
Whether benefits like these are physiological or psychological remains to be determined. Placebo rituals are common — and commonly effective — among athletes who believe a lucky shirt or ritual breakfast will help them. There's no harm in wearing compression garments for short periods of time if they give you a perceived boost, Skiba says. But there's no guarantee they'll help.
"My colleagues in elite sports are mostly unimpressed," he says. "There is definitely nothing I have read in the last five years that would make me say, 'Oh my God, everyone needs to use these.'"