If you’ve scrolled through Instagram recently, you may have seen ads for “bamboo detox foot pads.” The ads claim that if you stick the pads on the bottom of your feet before bed, the “toxins” in your body will be sucked out, resulting in better sleep and less stress. Their “proof?” When you peel them off, the pads will be coated with nasty-looking black stuff.

These products, which come in various incarnations, claim to contain naturally “detoxifying” agents like bamboo, charcoal, vinegar, and ginger. While some of these ingredients, like charcoal and vinegar, do have some health benefits, anything that claims to ‘detox the body’ is a misunderstanding of how our bodies actually work. Here’s what you need to know about the wellness trend.

Do detox foot pads work?

There is no evidence that detox foot pads do what they claim to do. In fact, the claims about “detoxification” or removing heavy metals from one’s body are so egregiously unsupported that in 2009, the Federal Trade Commission sued marketers of Kinoki “Detox” Foot Pads over deceptive advertising. The FTC claimed that “The defendants falsely claimed to have scientific proof that the foot pads removed toxic materials from the body.” In addition, the FTC argued that the marketers made “false or unsupported claims” when they said the pads could help with a variety of conditions, including depression, headaches, insomnia, diabetes, arthritis, and high blood pressure.

By 2010, the foot pads were banned and the marketers agreed to a judgment of 14.5 million dollars, though it was suspended based on the “defendants’ inability to pay,” according to an FTC press release.

The ruling prohibiting the sale of these products only applied to the companies that were defendants in the lawsuit. Since that time, more companies have sprouted up and haven’t faced similar lawsuits, perhaps because they make slightly less outlandish claims. I haven’t seen any products that specifically make the “heavy metals” claim; the claims are of more vague and unspecified “detoxification” properties, along with improved circulation and sleep.

Zachary Rubin, an allergist and clinical immunologist in Illinois says products that claim to detoxify the body are often a red flag.

Manufacturers of these products generally do not have scientific studies to back up their claims, Rubin tells Inverse. “Often, they are not regulated by the FDA so it is unclear whether these products meet basic safety standards. It is important to read labels carefully because these products may contain chemicals that can irritate the skin.”

Indeed, one reviewer of a detox foot pad product on Amazon notes that the adhesive on certain brands of these products was so strong that they had to scrub to get it off. And the gross black stuff you see on the pads after use? Experts say it’s likely a mixture of sweat and one or more of the ingredients in the patch.

How does our body eliminate toxins?

While the idea of ridding your body of any harmful might seem appealing, it’s probably already happening.

Our bodies are constantly trying to achieve homeostasis or a state of balance, Rubin says. “This is very important for our bodies to function properly. The main organs that excrete waste are the liver, kidneys, and skin in the form of feces, urine, and sweat. If you take too much of something, our body does a good job of removing most of it through these means.”

It’s not perfect, of course. Certain kinds of substances do tend to stick around, but there’s no evidence that foot pads can do anything your liver, kidneys, or skin can’t.

Why are detox products so popular?

The popularity of products that claim to detoxify the body is evident in the billions of dollars companies earn. In 2020 alone, the Global Detox Market was valued at more than 48 billion dollars.

“Products that promise to ‘detoxify’ your body are very popular because they often give the illusion that they will be “quick fixes” for various health issues,” Rubin says. “Unfortunately, we do not understand all of our ailments, and these types of products offer expensive promises that don’t necessarily deliver results.”

The illusion can be harmful to how the public understands health and their own body, Rubin says because the products “may provide inaccurate information on how the body works and offer ‘quick fixes’ for health issues. This may create mistrust in the medical community when a healthcare professional does not agree with using these types of products. It can become a slippery slope.”

The bottom line: Be skeptical of any wellness product that claims to be a quick fix for a complex health issue.