The study, conducted by Teri Krebs and Pål-Ørjan Johansen at the Norwegian University of Science and Technology, reached the conclusion after analysing data from a US national health survey (Krebs & Johansen, 2013).
Among the 130,000 participant, 22,000 had taken psychedelic drugs like LSD, peyote or magic mushrooms at some point in their lives. Participants were asked about whether they’d had treatment for mental health problems, or experienced psychosis, depression, or other psychological distress.
After adjusting for risk factors, like age and exposure to very stressful events, they found no connection between either recent or lifetime use of psychedelics and increased rates of mental health problems.
In fact, there was some weak evidence of the positive effects of psychedelics.
The researchers also found no evidence of ‘acid-flashbacks’ or other strange perceptual phenomena among people who had used psychedelics. Moreover, as they explain in the paper, published in the journal PLOS ONE:
“Psychedelics often elicit deeply personally and spiritually meaningful experiences and sustained beneficial effects. [However,] psychedelics can often cause [a] period of confusion and emotional turmoil during the immediate drug effects and infrequently such adverse effects last for a few days after use.”
This result fits in with other studies which find that, unlike many other illicit drugs, psychedelics are not addictive and do not promote compulsive use:
- A study of long-term peyote use by Native Americans found no evidence of psychological or cognitive deficits (Halpern et al., 2005).
- Amazon rainforest dwellers who had used dimethyltryptamine—which is similar to psilocybin, the active ingredient in magic mushrooms—in over 360 religious ceremonies had no psychological or cognitive deficits (Bouso et al., 2012).
Researcher, Pål-Ørjan Johansen explained:
“Everything has some potential for negative effects, but psychedelic use is overall considered to pose a very low risk to the individual and to society. Psychedelics can elicit temporary feelings of anxiety and confusion, but accidents leading to serious injury are extremely rare.”
What this study can’t tell us is whether psychedelic drugs could be good for some people and bad for others and the results even out.
That said, Teri Krebs concludes:
“Over the past 50 years tens of millions of people have used psychedelics and there just is not much evidence of long-term problems.”
Image credit: Evan