Meditation is now widely promoted as a tool for everything from reducing stress to improving productivity. It has become a go-to approach for supporting mental well-being across many settings.
However, when a practice like meditation is used in medical or therapeutic contexts, important scientific questions arise. How much practice is needed to produce benefits? And just as critically, are there any risks or unwanted side effects associated with it?
"This is the kind of research that is done at the very beginning of developing any new treatment intervention program," explained Nicholas Van Dam, a psychologist at the University of Melbourne. "And for various complex reasons, with mindfulness-based programs in particular, that just didn't happen."
Exploring the Possible Downsides of Meditation
While many people report positive outcomes, research over the years has also revealed that meditation can lead to adverse experiences for some individuals. These side effects may include panic attacks, intrusive or distressing memories related to past trauma (as seen in post-traumatic stress disorder), and in more extreme cases, sensations of depersonalization or dissociation.
Van Dam noted that estimates of how common these experiences are vary widely in the scientific literature. Some studies suggest that only about 1% of meditators experience side effects (Wong et al., 2018), whereas others report figures as high as two thirds (Britton et al., 2021).
To clarify these inconsistencies, Van Dam and his colleagues conducted a study published in Clinical Psychological Science to investigate how frequently meditators encounter side effects and what factors might increase the likelihood of experiencing them.
A Nationwide Study of Meditation Experiences
The research team recruited nearly 900 adults from across the United States. To ensure the group reflected the broader U.S. population of meditators, they used data from the Centers for Disease Control and Prevention to guide participant selection. The researchers also recruited meditators from a wide range of skill levels, from beginner to advanced, "such that we could kind of get a sense of the full sample of people who engage in meditation within the U.S.," Van Dam said.
Van Dam emphasized that the way researchers ask about side effects can dramatically influence the findings. "The devil is in the details," he said, explaining that many previous studies rely on open-ended questions, a method known as spontaneous reporting. In such cases, participants might not recognize their experiences as side effects or may hesitate to mention them.
To reduce that uncertainty, Van Dam's team developed a 30-item checklist covering possible effects of meditation. Participants rated the intensity of each effect, whether it was positive or negative, and whether it interfered with their daily functioning.
What the Data Revealed
The results showed that nearly 60% of U.S. meditators reported at least one side effect listed on the checklist (for example, feeling anxious or disembodied). About 30% said they experienced effects that were challenging or distressing, and 9% reported that these effects caused functional impairment.
The study also identified several potential risk factors. Individuals who had experienced mental health symptoms or psychological distress within the 30 days before meditating were more likely to report adverse effects. Those who attended intensive residential retreats, which often involve long periods of silent meditation, were also more likely to experience functional impairment.
Van Dam noted that more research is needed to determine cause and effect. A prospective longitudinal study, he said, would help clarify how mental health and meditation interact over time.
Encouraging Awareness, Not Fear
Despite these findings, Van Dam cautioned against viewing meditation as dangerous. "Our conclusions are not that people should be terrified, or people should not try meditation. It's really that we think that we should do a better job of providing informed consent," he said.
He compared the situation to other therapeutic treatments, such as surgery or exposure therapy, where patients are told in advance what they might experience. This preparation allows individuals to weigh risks and make informed decisions about their participation.
Navigating Discomfort in Mindfulness Practice
In meditation, this kind of pre-discussion often doesn't happen. "We have to find a way to have that conversation and navigate that space," Van Dam said. He suggested that practitioners and clinicians should explain that discomfort can sometimes be part of the process. Feelings of unease or questioning one's sense of self are not necessarily signs of harm but rather potential aspects of deep psychological exploration. However, distress that significantly interferes with daily functioning should be taken seriously.
"These practices are not for everyone," Van Dam concluded. "If they're not working, it's not necessarily because the person is doing something wrong. It might be because it's just not a good match."