Mindfulness meditation has become increasingly popular in the United States and around the world in recent decades. Apps such as Headspace, Calm and Plum Village – inspired by the Vietnamese Buddhist monk Thich Nhat Hanh – are helping people build a steady practice, reduce stress and improve sleep.
The practice, which involves paying attention to present-moment experience with openness and awareness, is also taught in public schools and workplaces in the United States. In addition, evidence-based mindfulness programs are frequently used in U.S. hospitals and clinics. Legendary former NBA coach Phil Jackson, has even encouraged practicing mindfulness on the basketball court.
The benefits of mindfulness in reducing stress, anxiety and depression have been widely documented. However, mindfulness does not affect everyone in the same way. A growing body of research points to unwanted or adverse effects in some people. These include anxiety, emotional distress, resurfacing of painful memories and dissociation – feeling detached from oneself or one’s surroundings.
Most people do not experience these lasting problems, but researchers are increasingly trying to understand why they occur in a minority of practitioners.
As a scholar of Buddhism, I have studied traditional contemplative practices and also followed the growing scientific research on their effects. I believe some of the confusion arises because Buddhist traditions have long expected that meditation can sometimes be difficult, whereas mindfulness is often presented primarily as a way to reduce stress and promote relaxation. In many Buddhist traditions, meditation is learned from experienced teachers who can guide the practitioner and help manage difficult experiences that might arise.
The scientific debate
Scientists do not always agree on what counts as an adverse effect of mindfulness. Some make a distinction between temporary discomfort – such as anxiety or difficult emotions during meditation – and lasting harm, such as worsening mental health symptoms. Others take a broader approach, measuring a wider range of difficult experiences that occur during or after meditation practice, including intrusive memories and lasting emotional distress.
A 2017 survey of meditation practitioners found that about 25% reported unwanted effects, such as anxiety, fear or unsettling thoughts. Most, however, said these were temporary and did not require medical attention.
Other studies have identified more serious effects. In another widely cited study from 2017, researchers interviewed 60 experienced Buddhist meditation practitioners who had reported challenges that they associated with their meditation practice. These included severe anxiety, traumatic memories, altered perceptions and difficulties functioning in everyday life.
A 2021 study of meditators in the United Kingdom found that lasting effects, such as feeling constantly on edge or detached from oneself or one’s surroundings, occurred in roughly 6%–14% of participants.
Some participants viewed these experiences as valuable parts of their meditation practice. Others found them to be distressing and disruptive.
Estimates of how many practitioners are affected vary widely across studies, but evidence suggests they affect only a minority.
The Buddhist perspective
Many people today turn to mindfulness, expecting stress reduction and relaxation. In Buddhist traditions, however, meditation serves other purposes. Buddhist texts often present meditation as a way of confronting uncertainty, grief, mortality and impermanence.
In the Pali canon, the earliest collection of Buddhist texts, the “Maraṇasati Sutta” teaches practitioners to reflect on the certainty and unpredictability of death. Another text in the Pali canon, the “Upajjhatthana Sutta,” guides readers to reflect on aging, illness and death, and to take responsibility for one’s actions.
Meditation is often used to face the realities of human existence. Difficult emotions may arise, and they are not always seen as signs that something is wrong. The texts speak of approaching these reflections with “fearlessness.”
Understanding difficult experiences
Why do some people experience meditation-related difficulties, while others do not? One important factor may be the context in which it is practiced.
In clinical settings where mindfulness is used as part of treatment, some difficult experiences, such as temporary sadness or anxiety, may simply be part of working through difficult emotions rather than signs of harm.
Clinical psychologist Willoughby Britton distinguishes between temporary distress and experiences that negatively affect daily functioning. Temporary distress is part of the treatment, but it may be considered an adverse effect if it persists, worsens or significantly impairs functioning.
Other researchers compare mindfulness with psychotherapy, exercise and medication and argue that soreness after exercise, while unpleasant, is not necessarily evidence of harm.
Why guidance matters
This distinction between expected discomfort and lasting harm echoes long-standing features of Buddhist traditions. Difficult experiences are not always seen as signs that something has gone wrong. They may instead be understood as part of the process of learning through meditation.
Buddhism assumes that meditation is learned from experienced teachers. Practice frequently occurs within a monastic or lay community. Training typically proceeds step by step, beginning with living ethically, then learning to focus the mind and finally gaining deeper understanding.
Modern mindfulness often presents meditation as something people can learn on their own, whereas Buddhist traditions emphasize learning meditation from experienced teachers and practicing within a community. Research also suggests that support may influence how difficult experiences are interpreted and managed.
Researchers have also found that “influencing factors” such as relationships with teachers, meditation instructions and support from one’s meditation community play a role. The same experience could be disruptive for one practitioner but manageable for another, depending on how it was interpreted and supported.
What scientists are learning and why
The question is no longer “Does mindfulness work?” Scientists now ask: “For whom does it work?” “Under what conditions?” “What kinds of support are needed?” To answer these, there is growing interest in screening, safety protocols and individualized approaches.
For example, some programs now ask about trauma or mental health history before beginning mindfulness training. Others encourage participants to work with a trained instructor and adjust or stop practices if they become overwhelming.
It has become clear that mindfulness is neither a cure-all nor inherently dangerous. It remains beneficial for most people. Difficult experiences should neither be ignored nor automatically treated as failure.
For many people, mindfulness apps and self-guided practice work well. Some who experience problems may benefit from working with a trained instructor or in a structured program.
