When sales go stale, embrace the romanticism of exoticism.
That is one of the tricks of the wellness industry: selling gadgets and procedures that come from ancient traditions far, far away. There is, after all, an endless supply of folk remedies that can be repackaged for a modern audience suspicious of medicine but desirous of all-natural lotions and potions.
Enter gua sha. You may have seen it endorsed by the queen of wellness herself, Gwyneth Paltrow, or by legions of beauty influencers. Recently, rising star Hudson Williams from Heated Rivalry was seen smoothing out his skin with a gua sha tool in a viral (and delightfully unhinged) skincare routine video published by The Cut. Looking like a symbolic heart stretched thin, the gua sha stone most often used is made of jade, and we are told to gently stroke our face and neck with it to get rid of puffiness.
But the version modeled on social media is heavily diluted from true gua sha, which leaves red-and-purple bruises no Instagram star would want on their face.
How spooning might work
Gua sha hails from China, although the practice has also become popular in Southeast Asia. It has been traced back to nearly 2,000 years ago, near the end of the Han dynasty. The word gua translates to “scraping” or “scratching,” while sha can mean a number of things, including “sand,” “shark-skin,” or a “red, raised rash.” Basically, you gua until you see sha.
This old remedy begins by lubricating the skin—often the back, the chest, or stomach—and then using a tool with a smooth edge. Some people recommend using the flat side, while others use the edge itself. The tool can be a piece of jade stone, a metal jar cap, a piece of animal horn or bone, or even a thick ginger root. In 2012, a survey of 3,209 adults in Hong Kong revealed that nearly a quarter of them had used gua sha in the last year and their preferred tool for the technique was a simple spoon.
The gua sha tool is used to stroke the oiled-up skin repeatedly, in one direction, with a fair amount of pressure applied to it until blemishes start to appear. The pressure causes blood vessels under the skin to burst, creating ecchymoses that heal after a few days. This process is claimed to heal just about anything, from respiratory problems to fevers, from vomiting to constipation. In Vietnam, it is called cao gio; in Indonesia, kerik or kerokan; while English has preferred words like coining or scraping—even spooning, not to be confused with what couples do for comfort, which shouldn’t leave any mark.
To the uninformed eye, the bruises of gua sha can look like physical abuse, and the medical literature is peppered with warnings to healthcare providers. If the bruises, sometimes described as tiger stripes, are linear and symmetrical (especially if the patient is Asian), think gua sha. To be honest, though, some of the photos published in the literature show bodies that look like crime scenes, where the purplish-red bruising’s linearity and symmetry are not easy to observe. A 43-year-old Chinese woman was seen in the emergency room of an Italian hospital because of abdominal pain, and when the staff noticed the masses of ecchymoses on her back, they got suspicious. But the patient only spoke Chinese and wouldn’t admit what had happened to her own son. A cultural mediator arrived, and the patient finally confessed to having received gua sha treatment for her pain.
The reasoning behind gua sha originally comes from pre-scientific beliefs about how the human body works. Illnesses were ascribed to a stagnation of a life force called qi. By scraping the skin, the idea was that, like a blocked pipe tended to by a plumber, flow could be restored. As we learned more about human biology, the explanation had to shift away from unscientific notions of qi and toward molecular phenomena that might account for the putative benefits of gua sha. All sorts of ideas have been hypothesized: anti-inflammatory effects conjured up by the need to clean up the heme in those bruises; a tweaking of the production of nitric oxide due to blood vessel injuries; and an inhibition of how nerves detect pain.
There’s also a simpler theory when it comes to how using gua sha for pain might help. When we hurt our foot, what’s the first thing we do? We grab it and rub it. The sensation overrides the pain from the injury, at least temporarily. Similarly, ointments like Tiger Balm work by acting as counterirritants. Rubbing a spoon on the area might likewise cause a counterirritation that makes our brain less able to feel the original pain—for a short period of time.
This simple theory, which demotes gua sha to a league of run-of-the-mill counterirritants, doesn’t sound right to some. One of the most preposterous papers I’ve read in a while comes from a Chinese team that performed gua sha once on nine young women, drawing their blood before and after the procedure and looking at changes in messenger RNA expression. We are talking tens of thousands of mRNA molecules—short-lived transcripts from genes—to see what went up and what went down after gua sha, a massive fishing expedition. It turns out that the changes they saw were very specific to each woman and hardly anything changed consistently in all of them… except for the transcripts from three histone genes. The proteins encoded by these genes are the rolls around which our DNA is spooled, so they play a role in just about anything our bodies do, including the immune system. And this is where the authors land, claiming that these “subtle” changes in histone expression have something to do with immune function, and this may be how gua sha works. It’s anomaly hunting, but because it takes the form of a scientific paper, it can be weaponized by people looking to validate skin-scraping as a health intervention. It’s nonsense.
None of this hypothesizing on how it works can answer the real question of does it work.
Is it the oil? the massage? the bruising?
Having read dozens of papers on gua sha, I can say that their failings are exactly what we are used to when it comes to alternative medicine: small studies done at single centres with no long-term follow-up, in which the control group comparison is problematic. Basically, you can’t blind people to gua sha. There is no placebo gua sha that doesn’t also do what gua sha does. Experimenters resort to heating pads, standard of care, or wait lists, which means that at best we can say that doing gua sha can be better than doing nothing. When a patient dealing with chronic pain gets recruited into a study in which a person strokes their body for 15 minutes after being told that this might help with pain, is it any wonder that they report that their pain has gone down? Placebo effects are common, and these studies do not manage to subtract them from the equation.
Moreover, the oil used to lubricate the skin in these studies is often an ointment called Tumarol, which is medicated with camphor, eucalyptus oil, and menthol. If we compared a group receiving gua sha with a group being rubbed with Tiger Balm, would they report the same benefit? Or is it the massage itself, regardless of the tool used or the specific motion, that benefits the patient, in which case we can do away with the unnecessary bruising? We simply do not know. A common claim is that gua sha improves blood circulation in the area being massaged. This much is obvious: it is a type of massage, after all, but the effect on circulation, as seen in two very small studies, is temporary. Does it help in any way? Hard to tell.
Also, the lion’s share of the studies are done in China. I read too many scientific papers that introduced gua sha as “generally regarded as effective” or as having an “effectiveness rooted in the extensive empirical knowledge dating back to ancient times.” Chinese researchers are proud of gua sha. A similar nationalistic pride has contaminated the Chinese literature on acupuncture, whereby every trial of acupuncture done in China “proves” it works… but trials done elsewhere are much more muted.
Gua sha has an advocate outside of China, though. Arya Nielsen is part of the faculty at Beth Israel Medical Center in New York City and she has published numerous papers about gua sha. She lists a Bachelor’s degree in English and Philosophy, a Master’s degree in Community Organization and Advocacy, and a Ph.D.in Interdisciplinary Studies, Integrative Medicine, and Health Research. In her defense, she has published a safety protocol to minimize the potential harms of gua sha—by teaching practitioners to wear gloves and use a disposable stroking device like a metal cap to minimize the transmission of infectious microbes—but her use of the phrase “hegemony of science” is quite telling. Among believers in alternative medicine, science can be annoying when it shows these practices don’t work. Experience and anecdotes are often promoted instead, which are pretty terrible forms of evidence.
The risk of infection Nielsen outlines, though, is real and is not the only possible harm from gua sha. You can see that reusing the same stone on multiple patients without disinfecting it is not a good idea. The bruises are under the skin, sure, but tiny cuts may result from the treatment and the stone picks up blood-borne microorganisms and delivers them to the next patient who gets accidentally cut. One such patient was reported on a few years ago: she developed nodules and pustules on her arms and legs, filled with bacteria called Mycobacterium massiliense. She had to be put on antibiotics and have her nodules drained every month for nearly half a year.
Another patient could hardly talk and had bright red striations on his neck: his epiglottis had enlarged after receiving gua sha and he had to be injected with steroids to reduce the inflammation. Some will argue that gua sha should not be performed on the neck, but when a practice is unregulated and becomes popular, you never know how well trained the person caring for you is.
The good news is that serious complications from gua sha appear to be very rare. The often-repeated warning that the stroking can induce burns is a misrepresentation: it was actually a case of fire cupping gone wrong in Vietnam. But many studies of gua sha fail to report adverse events, so it’s possible that complications are underreported.
Gua sha is intense and it leaves you looking bruised. What we see on Instagram has little to do with this ancient practice.
Magic mirror on the wall, youth is the fairest one of all
So, does rubbing your face with a stone remove puffiness?
The closest thing I can think of is manual lymphatic drainage. Lymph is a clear fluid, a derivative from blood, full of immune cells, and some people experience swelling that is due to an abnormal accumulation of lymph somewhere in the body. It can happen, for instance, after treatment for breast cancer. A therapist can use their hands on the swollen body part in an attempt to move this accumulated lymph into a nearby lymph node. The evidence for its effectiveness is not great, however, when it comes to using it in the context of breast cancer care. Does it do anything when you think your face is a bit swollen? I have no idea, but if there is an effect, it’s likely to be minimal and temporary.
Why do influencers swear by running a stone across their face? Probably because they’re young and they already have really good skin, and it’s easy to register tiny changes when you want to see them. If these influencers want to keep that supple skin as long as possible, there are more evidence-based things to do than stroking their face with a jade stone: wearing sunscreen to avoid photoaging and refusing to smoke.
We may want to refer to the Instagram and TikTok version of the practice as gua, since there is no sha. As for the actual, bruise-inducing gua sha treatments that can seemingly help with everything, the old saying is worth trotting out once again: if something is claimed to treat everything, it probably doesn’t treat anything. Gua sha will need more than a spoon or a jar lid to smooth out the many wrinkles in its scientific literature.
Take-home message:
- Gua sha is a popular practice in Asia where an edged tool is used to massage the body until bruises appear, and the technique is claimed to help treat any health problem
- Studies of gua sha’s alleged health benefits are small and do not manage to exclude placebo effects, since there is no placebo version of gua sha
- One of the main risks is infection if the tool is reused on multiple patients without being properly sanitized, as gua sha can create small cuts and pick up disease-carrying microorganisms
- A softer version of gua sha is popular on social media, where influencers smooth out their face without creating bruises, but the effect of this massage on puffiness is unlikely to be significant
