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For the past five years or so, barely a week has gone by without a study, comment, or press release about the potential benefits of psychedelic drugs landing in my inbox.

Psychedelics are drugs that change the way we experience the world. They can alter our senses and make us hallucinate. But they can also trigger experiences that are more difficult to define, such as “openness” and “expansion of consciousness.”

The reputation of psychedelics like psilocybin and LSD has been through something of a rollercoaster ride over the last 70 years or so. They went from generating excitement to instilling fear and mistrust, at least if media coverage is anything to go by. But they’ve experienced a recent renaissance.

A growing number of academic researchers, therapists, and companies are interested in the potential of psychedelics to treat mental-health disorders such as depression, anxiety, post-traumatic stress disorder (PTSD), and substance use disorders, to name a few.

Most recently, I came across a paper making the case that psychedelics could be useful in treating obesity. The paper, written by Nicole Fadahunsi and her colleagues at the University of Copenhagen in Denmark, argues that if psychedelics can change our behavior, and potentially get people off addictive substances, they might also help others change their unhealthy eating habits. The authors believe that psychedelics might also make people more open to other approaches to weight loss, such as lifestyle changes.

We don’t yet have any good evidence to support this claim. There is some, albeit limited, evidence that psychedelics might help some people with depression and PTSD. A handful of trials suggest that MDMA, otherwise known as ecstasy, can improve the symptoms of people with severe PTSD, for example. A trial published last year suggests that psilocybin is as effective at treating depression as a commonly used antidepressant.  

But these trials have been criticized. Take the psilocybin study, for example. It set out to test whether the drug could lower participants’ depression symptoms by a certain degree, as measured using a questionnaire. It did not meet this goal. The study’s authors wrote that “no conclusions can be drawn from this data.”

That didn’t stop the study’s lead author, Robin Carhart-Harris, then at Imperial College London in the UK, from claiming in an article in The Guardian, just five days after the study’s publication, that “psilocybin appear[s] to be a more successful treatment for depression than a typical antidepressant.”

In that same article, the scientist wrote that he believes we are on the verge of “a paradigm shift in mental healthcare linked to an improved understanding of the origins of depression, and how we can most effectively treat it.”

Other researchers have questioned whether the trial should have been published at all. “We wondered why the editors published an underpowered, short-term, phase 2 trial that could not support any clinical conclusions,” Wayne Hall of the University of Queensland in Australia and Keith Humphreys at Stanford University in California wrote in a different journal a couple of months ago.

“Unfortunately, psychedelic drugs have come to recent prominence through the unwise lowering of research standards by some major medical journals and the inappropriate exaggeration of research results in the popular media by scientists,” the pair wrote. Ouch.

I have to say that as someone who has been following this research for the last 10 years, I agree to some extent. It feels as though the mood has swung too sharply—we’ve gone from disapproving of these illicit substances to hailing them as wonder drugs. The truth is we don’t yet have evidence that psychedelics really are going to change health care.

Some believe that psychedelics research is “trapped in a hype bubble.” A trio of researchers at Johns Hopkins University in Baltimore—two of them working at the university’s Center for Psychedelic and Consciousness Research—think that belief and investment in psychedelics as a cure-all for mental-health disorders have peaked. The bubble is about to burst, they wrote in August.

I hope it is. There is plenty of fascinating work underway in the field that doesn’t need to be hyped. We are still learning exactly what psychedelics do to our brains, but studies suggest that some act to increase plasticity—the ability to reshape neural circuits and form new connections. Given the importance of plasticity for learning, it’s likely that psychedelics—or at least some compounds isolated from them—will benefit some people, in some circumstances.

Obesity might be a bit of a stretch. But my mind is open to convincing, solid data—without the need for psychedelics.

Read more from Tech Review’s archive:

MDMA does seem to have helped Nathan McGee, who took the drug as part of a clinical trial. He told my colleague Charlotte Jee that he “understands what joy is now.” 

Some researchers are trying to re-create the experience of taking psychedelics using virtual reality. Hana Kiros gave it a go. 

Others are using AI to analyze “trip reports” to figure out what exactly psychedelic drugs do to our brains, I reported in March. 

There’s lots of anecdotal data to draw from. Plenty of people are sharing stories of their own experiences with psychedelics online, as Taylor Majewski reported earlier this year.

From around the web:

Ten thousand people died from covid-19 last week. But the World Health Organization hopes that at some point next year, it can say the virus no longer represents a global health emergency. (WHO) 

Covid cases are surging in China as restrictions are lifted, and authorities are urging people not to panic-buy fever medication, painkillers—and canned peaches. (CNN)

Telehealth websites are leaking users’ sensitive health information to tech companies. An investigation has found that people’s personal, identifying data, along with information on their mental health, is being shared with Facebook. (STAT)

A personalized mRNA cancer vaccine has performed well in a phase 2 clinical trial, according to an announcement by pharma companies Moderna and Merck. When used alongside an existing drug, the mRNA vaccine reduced the risk of cancer recurrence or death by 44% over use of the existing drug alone. (Moderna)

Volunteers with depression are having 14 electrodes implanted into their brains to better understand and treat their symptoms. Neuroscientists have used the data collected so far to create a “mood decoder.” “Depression is like a constant weight on your soul,” one volunteer who had his brain stimulated told me. “When they touched that perfect little spot, that weight lifted.” (MIT Technology Review)