Sustained, multifaceted improvements in mental well-being following psychedelic experiences in a prospective opportunity sample

This survey (n=654 start; n=64 end) found that those who used psychedelics (by themselves; naturalistic observational study) improved in ‘being well’ and ‘staying well’, but found no changes in ‘spirituality’. The study ran for two years and also measured the well-being of the participants before, two weeks after, and four weeks after the experience.


Introduction: In the last fifteen years, psychedelic substances, such as LSD and psilocybin, have regained legitimacy in clinical research. In the general population as well as across various psychiatric populations, mental well-being has been found to significantly improve after a psychedelic experience. Mental well-being has large socioeconomic relevance, but it is a complex, multifaceted construct.

Methods: In this naturalistic observational study, a comprehensive approach was taken to assessing well-being before and after a taking a psychedelic compound to induce a ‘psychedelic experience’. Fourteen measures of well-being related constructs were included in order to examine the breadth and specificity of change in well-being. This change was then analysed to examine clusters of measures changing together. Survey data was collected from volunteers that intended to take a psychedelic. Four key time points were analysed: one week before and two weeks, four weeks, and two years after the experience (N = 654, N = 315, N = 212, and N = 64 respectively).

Results: Change on the included measures was found to cluster into three factors which we labelled: 1) ‘Being well’, 2) ‘Staying well’, and 3) ‘Spirituality’. Repeated Measures Multivariate Analysis of Variance revealed all but the spirituality factor to be improved in the weeks following the psychedelic experience. Additional Mixed model analyses revealed selective increases in Being Well and Staying Well (but not Spirituality) that remained statistically significant up to two years post-experience, albeit with high attrition rates. Post-hoc examination suggested that attrition was not due to differential acute experiences or mental-health changes in those who dropped out versus those who did not.

Discussion: These findings suggest that psychedelics can have a broad, robust and sustained positive impact on mental well-being in those that have a prior intention to use a psychedelic compound. Public policy implications are discussed.

Authors: Keri Mans, Hannes Kettner, Eline C. Haijen, Mendel Kaelen, David Erritzoe & Robin L. Carhart-Harris


If we step outside of the lab for a moment, can we find the same improvement in well-being? Can we find the sustained positive impact on mental well-being that many studies have reported on? That is what the current study tries to grapple with.

A survey among those who took psychedelics questioned the participants on fourteen aspects of well-being. They measured this a week before the experience, two and four weeks after, and two years later. At the first moment, 654 participants answered the questions, after two years they were able to gather results from 64 people.

This is what changed in their well-being

  • The themes ‘being well’ and ‘staying well’ improved and stayed elevated throughout the study
  • The theme ‘spirituality’ didn’t change from the baseline measure
  • Changes in well-being negatively correlated with psychological inflexibility and depressive symptoms

A survey study like this is able to answer the question of what happens in real life for those who use psychedelics. The current study was done with those who had already done psychedelics before (90%) and a future study could possibly see if the same results (or better results) can be found for those who haven’t used psychedelics before. And finding out what specifically, for those without mental illness, during the psychedelic experience leads to these positive outcomes.

As the authors say in the introduction and conclusion, understanding how psychedelics can help those who are ‘well’ could help strengthen them against adversity (e.g. lockdowns, grief). And in turn this could lead to fewer people falling into the ‘unwell’ category. And who doesn’t want their well-being to improve?

This study is a follow-up to Haijen and colleagues (2018) which didn’t include the follow-up data and grouping of themes.


Mental well-being can be seen as (in part) the opposite of mental illness. And where mental illness is currently one of the leading causes of disability in the world, improving mental well-being could move people back up this continuum towards the more positive side.

The current study defines mental well-being as ‘positive mental health’ or ‘flourishing’. And at the same time recognizes that no single definition has been generally accepted.

The paper investigates this side of the spectrum (whereas many other studies focus on mental illness). The authors argue that psychedelics may be a tool to help improve the well-being of those not (currently) suffering from mental illness.

“It is suggested that, besides alleviating symptoms in clinical populations, initiatives and interventions for people that are already “well” could serve to further promote wellness and mitigate risk of mental illness.”


The participants took part in the 2017 Psychedelic Survey. They had planned to partake in a psychedelic experience and were then queried at six different time-points (-7, -1, +1, +14, +28d, +2y).


Well-being scores improved significantly. They also correlated with other such as self-esteem, mindfulness, resilience, emotional stability, gratitude, presence (meaning). The inverse was true (negative correlation) for scores of psychological inflexibility, and depressive symptoms.

Based on this data, the researchers found three underlying factors (exploratory factor analysis) and dubbed them ‘being well’, ‘staying well’, and ‘spirituality’. Of these, the first two were found to be sustained (higher) two years after the experience.

An analysis of the drop out (attrition) of participants didn’t show anything to worry about (e.g. that only the most positive participants filled in the last survey).


“These findings lend support to the view that psychedelics have a general positive effect on well-being; promoting psychological wellness and resilience in the medium to long-term.”

The current study was done ‘in the field’ which means that the ecological validity is high. Or in other words, it generalizes to others who are using psychedelics by themselves outside of clinical trials.

There are however limitations to the current methodology. The participants were self-selection (a subsection of those who already use psychedelics, and want to fill in a survey, etc). And although no abnormalities were found in the data, the high attrition rate (leaving about 10% of participants at the 2 year follow-up) could lead to a response bias.

Used with care, psychedelics may have potential to complement early intervention or prophylactic strategies, e.g., using lowdose psychedelic therapy to improve receptivity to, and enhance the action of, mindfulness-based practises designed for this purpose.

Study details

Topics studied
Healthy Subjects

Study characteristics



Authors associated with this publication with profiles on Blossom

Mendel Kaelen
Mendel Kaelen is a neuroscientist and entrepreneur, researching and developing a new category of psychotherapeutic tools for care-seekers and care-providers. Mendel has researched the incomparable effects of music on the brain during LSD-assisted psychotherapy. His work has determined how LSD increases enhanced eyes-closed visual imagery, including imagery of an autobiographical nature. This gives light to how music can be used as another dimension in helping psychotherapists create the ideal setting for their patients.

David Erritzoe
David Erritzoe is the clinical director of the Centre for Psychedelic Research at Imperial College London. His work focuses on brain imaging (PET/(f)MRI).

Robin Carhart-Harris
Dr. Robin Carhart-Harris is the Founding Director of the Neuroscape Psychedelics Division at UCSF. Previously he led the Psychedelic group at Imperial College London.


Institutes associated with this publication

Imperial College London
The Centre for Psychedelic Research studies the action (in the brain) and clinical use of psychedelics, with a focus on depression.

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