Some types of alternative medicine, such as homeopathy and Reiki, should not be tested in clinical trials anymore because the therapies are not grounded in science, and studying them is like testing whether magic works, some researchers argue.
In a new paper, Dr. David Gorski, of Wayne State University School of Medicine and Dr. Steven Novella of Yale University, say that it is unethical to study alternative medicine therapies in people if those therapies violate well-established laws and theories of science. The chances that such therapies will work better than a placebo are "close to impossible," they say.
"There are some treatments that are so incredibility implausible" that there is no need to test them, Gorski said. "The likelihood of any positive result is so infinitesimally small." [Wishful Thinking: 6 'Magic Bullet' Cures That Don't Exist]
Such treatments are examples of complementary or alternative medicine (CAM), which broadly refers to treatments that fall outside of mainstream medicine.
For example, homeopathy is a CAM approach that is based on the idea that diluting a substance makes it stronger, and that water can retain a "memory" of a substance, which goes against multiple laws of physics, they said.
In order for homeopathy to work, "a lot of what we understand about physics and chemistry would have to be not just wrong, but spectacularly wrong," Gorski said.
Yet there have been many studies of homeopathy in people over the last several decades, the researchers said. For example, they pointed to a recent study conducted in Honduras in 2006 that looked at whether giving children dilutions of arsenic or the chamomile plant could treat childhood diarrhea. The study found that the tablets did not help the children.
Another CAM approach that is based on dubious science is Reiki, Gorski and Novella said. Reiki involves manipulating a patient's "healing energy," but there is no scientific evidence that this energy exists, they said.
Some supporters of the alternative medicine therapies argue that human trials will determine once and for all whether these therapies work. But this is a misguided view, Gorski and Novella said, because people who believe in such therapies are unlikely to stop using them even when studies show there is no benefit. "Such research only serves to lend legitimacy to otherwise dubious practices," Novella said in a statement.
Gorski and Novella said that, instead, more attention should be paid to whether a treatment is biologically plausible before it is tested in people. Some complementary and alternative medicine treatments have been tested simply because they are popular, and not because there is scientific evidence that justifies their study in people, Gorski said.
"What I advocate is that everything be held to the same scientific standard," Gorski told Live Science. "I reject CAM as a label, or as an excuse to do clinical trials on modalities that, if they were considered 'conventional,' would never muster the scientific interest or plausibility that would drive people to want to test it."
Unless researchers can show that there is a biologically plausible way these therapies could work to treat disease, or they have evidence that's so compelling that it makes researchers rethink basic laws of science, these therapies should not be tested in clinical trials, Gorski said.
"All clinical trials … should be based on scientifically well-supported preclinical observations [in lab studies] that justify them," they wrote in the Aug. 20 issue of the journal Trends in Molecular Medicine.
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Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.