Copper-infused compression garments are selling like crazy. Ranging from tight-fitting knee and elbow sleeves, to shirts, leggings, gloves and socks, these products are marketed as a way to relieve pain and improve sports endurance. One of the biggest purveyors of copper-infused athletic apparel, Tommie Copper, grossed about $87 million in sales between April 2011 and October 2014, according to court documents.

The only hitch? There’s little to no reliable scientific evidence that the copper/compression combo does what manufacturers are claiming. Which is why Tommie Copper and its founder Thomas Kallish agreed to pay $1.35 million to settle Federal Trade Commission charges that they deceptively advertised their copper-infused garments that are priced between $29.50 and $69.50. The proposed federal court order imposes an $86.8 million judgment, which will be partially suspended upon payment of $1.35 million by the defendants.

The FTC charged the company with falsely claiming that its products would treat or relieve chronic or severe pain (including pain and inflammation caused by diseases such as multiple sclerosis, arthritis, and fibromyalgia) and provide pain relief comparable or superior to the effects of drugs or surgery.

“It’s tempting to believe that wearing certain clothing will eliminate severe pain, but Tommie Copper didn’t have science to back its claims,” said Jessica Rich, Director of the FTC’s Bureau of Consumer Protection. “If you see an ad for a product that promises to replace the need for drugs or surgery, talk to a healthcare professional before you spend your money,” Rich said in a statement from the FTC.

Why Combine Compression With Copper?

Tommie Copper and other makers of copper-infused compression clothing, including Copper Fit, Miracle Copper, and Copper Wear, are combining two theories with their products: that compression plus copper equals pain relief and boosted healing.

Compressing the site of an injury is the third step of the recommended treatment for injuries such as muscle strains and ligament sprains, known as RICE—Rest, Ice, Compression, Elevation. Compression works by limiting swelling while providing support to the injured area. Medical compression stockings have also been prescribed to help prevent leg swelling and blood clots in patients who’ve had surgery.

Copper, a soft, malleable metal, has long been touted as a folk medicine treatment to relieve pain and heal injuries. According to court documents, a 2012 Tommie Copper catalog claimed that, “Copper has been used for thousands of years to aid in reducing inflammation, growing and sustaining connective tissues and aiding in blood flow and oxygen transport,” and that it “provides immediate relief from inflammation… and harnesses the other well-known health benefits of copper.”

Claims Debunked

Consumer Reports has also reviewed the research into the use of copper to ease pain and has found little evidence of the metal’s ability to lessen aches. A 2013 study of 70 people with rheumatoid arthritis (a relatively large sample for this kind of research), published in the journal PLOS ONE, concluded that wearing a copper wrist strap did not help ease pain. “There are also no reliable studies supporting the healing powers of copper-infused fabrics,” says Consumer Reports medical director Orly Avitzur, M.D. “It’s extremely unlikely that these fabrics would provide any therapeutic benefit beyond compression for arthritis or pain,” Avitzur says.

Makers of copper-infused compression sports apparel have also made other unproven claims beyond those addressed in the court settlement. For example, Tommie Copper claims that its products “improve muscle recovery and performance,” and another purveyor called Primary Health Sports claims its compression sleeves “enhance sport performance." However, there is little evidence that shows the efficacy of compressing muscles to improve athletic performance. While some small studies have shown a slight improvement in performance and slightly faster recovery from muscle swelling and pain, most others, including studies of runners, cyclists, and kayakers, have failed to prove that wearing compression garments gave these athletes an edge. To date, there are no large-scale, well-designed studies that have revealed a meaningful link between compression garments and improved athletic performance.

Targeting Consumers

Tommie Copper’s compression garments have been marketed online, in television ads, infomercials, and video testimonials—including highly-produced videos featuring the inspiring stories of celebrity endorsers such as Olympic swimming star Dara Torres and rodeo champion Shawn "Copper Cowboy" Minor. In one infomercial, talk show host Montel Williams said, “Tommie Copper is truly pain relief without a pill.”

Tommie Copper has also advertised in magazines such as Arthritis Today, according to the FTC complaint. “Pain relief is top-of-mind for people with arthritis. It’s easy to understand how a product like this, which has no scientific basis but that has such a strong advertising campaign would appeal to people,” Avitzur says.

Tommie Copper did not respond to Consumer Reports’ request for an interview or a comment. According to the settlement, Tommie Copper and its founder neither admitted nor denied the allegations of the FTC's complaint.