Psychedelics and health behaviour change

Abstract

Healthful behaviours such as maintaining a balanced diet, being physically active and refraining from smoking have major impacts on the risk of developing cancer, diabetes, cardiovascular diseases and other serious conditions. The burden of the so-called ‘lifestyle diseases’—in personal suffering, premature mortality and public health costs—is considerable. Consequently, interventions designed to promote healthy behaviours are increasingly being studied, e.g., using psychobiological models of behavioural regulation and change. In this article, we explore the notion that psychedelic substances such as psilocybin could be used to assist in promoting positive lifestyle change conducive to good overall health. Psilocybin has a low toxicity, is non-addictive and has been shown to predict favourable changes in patients with depression, anxiety and other conditions marked by rigid behavioural patterns, including substance (mis)use. While it is still early days for modern psychedelic science, research is advancing fast and results are promising. Here we describe psychedelics’ proposed mechanisms of action and research findings pertinent to health behaviour change science, hoping to generate discussion and new research hypotheses linking the two areas. Therapeutic models including psychedelic experiences and common behaviour change methods (e.g., Cognitive Behaviour Therapy, Motivational Interviewing) are already being tested for addiction and eating disorders. We believe this research may soon be extended to help promote improved diet, exercise, nature exposure and also mindfulness or stress reduction practices, all of which can contribute to physical and psychological health and well-being.

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https://doi.org/10.1177/02698811211008554
Journal of Psychopharmacology
2022, Vol. 36(1) 12 –19
© The Author(s) 2021
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DOI: 10.1177/02698811211008554
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Introduction
Promoting healthy lifestyles in areas such as diet, physical activ-
ity, smoking and drinking has become a key priority area in the
public and private sector, with the present wellness market
reportedly valued at US$4.5T (McGroarty, 2018). Relevant to
this industry is the science of ‘health behaviour change’ devoted
to exploring and expanding the understanding of theories, deter-
minants and interventions in this area (e.g., Davidson and Scholz,
2020). Promoting healthier lifestyles is important as unhealthy
behaviours increase the probability of manifest disorders such as
obesity, diabetes, depression, cancer and cardiovascular disease,
as well as untold personal and familial suffering and significant
economic burden (World Cancer Research Fund/American
Institute for Cancer Research, 2018). Healthy lifestyles and men-
tal health are closely related (e.g., Nagasu et al., 2019) and
unhealthy lifestyle choices can cross over into pathology, with
substance abuse being a major contributor to premature death
(Case and Deaton, 2015). Tobacco and alcohol use in particular
constitute a substantial health burden, together accounting for
approximately 15% of global deaths (World Health Organization,
2017b, 2018). Both obesity (World Health Organization, 2020)
and physical inactivity (Ding et al., 2016) remain highly preva-
lent worldwide, despite several decades of public health cam-
paigns and policies intended to combat them.
Psychedelic1 compounds such as LSD (lysergic acid dieth-
ylamide), psilocybin (present in ‘magic mushrooms’) and DMT
(dimethyltryptamine, present in ayahuasca2 and other
preparations) may not seem like obvious tools for promoting
healthier living. However, plants and fungi with psychedelic
potential have been used by humans for centuries, if not millen-
nia, for holistic ‘healing’ of body and mind (Akers et al., 2011;
Lowy, 1971; Schultes, 1969). In the mid-20th century, aided by
the laboratory synthesis of mescaline, LSD and psilocybin, sci-
entists began to systematically test the effects of these com-
pounds, with hundreds of studies performed. Several of these
focused on the ability of psychedelics to promote traditional
psychotherapy—with positive results claimed in the treatment
of mood disorders and addictions, in particular. For example, a
systematic review of 21 studies published between 1949 and
1973 covering the use of LSD and psilocybin for treating depres-
sion reported that 79% of participants had clinician-judged
improvement after treatment (Rucker et al., 2016). In this period,
over 40,000 patients participated in more than 1000 published
Psychedelics and health behaviour change
Pedro J Teixeira1,2 , Matthew W Johnson3,
Christopher Timmermann4, Rosalind Watts2,
David Erritzoe4, Hannah Douglass4, Hannes Kettner4
and Robin L Carhart-Harris4
Abstract
Healthful behaviours such as maintaining a balanced diet, being physically active and refraining from smoking have major impacts on the risk
of developing cancer, diabetes, cardiovascular diseases and other serious conditions. The burden of the so-called ‘lifestyle diseases’—in personal
suffering, premature mortality and public health costs—is considerable. Consequently, interventions designed to promote healthy behaviours are
increasingly being studied, e.g., using psychobiological models of behavioural regulation and change. In this article, we explore the notion that
psychedelic substances such as psilocybin could be used to assist in promoting positive lifestyle change conducive to good overall health. Psilocybin
has a low toxicity, is non-addictive and has been shown to predict favourable changes in patients with depression, anxiety and other conditions marked
by rigid behavioural patterns, including substance (mis)use. While it is still early days for modern psychedelic science, research is advancing fast and
results are promising. Here we describe psychedelics’ proposed mechanisms of action and research findings pertinent to health behaviour change
science, hoping to generate discussion and new research hypotheses linking the two areas. Therapeutic models including psychedelic experiences and
common behaviour change methods (e.g., Cognitive Behaviour Therapy, Motivational Interviewing) are already being tested for addiction and eating
disorders. We believe this research may soon be extended to help promote improved diet, exercise, nature exposure and also mindfulness or stress
reduction practices, all of which can contribute to physical and psychological health and well-being.
Keywords
Psilocybin, serotonin, therapy, public health, interventions
1 CIPER - Faculty of Human Kinetics, University of Lisbon, Cruz Quebrada,
Portugal
2The Synthesis Institute B.V, Amsterdam, The Netherlands
3 Center for Psychedelic and Consciousness Research, Johns Hopkins
University, Baltimore, USA
4Imperial College London Psychedelic Research Group, London, UK
Corresponding author:
Pedro J Teixeira, Faculty of Human Kinetics, University of Lisbon,
Estrada da Costa, Cruz Quebrada 1499-002, Portugal.
Email: pteixeira@fmh.ulisboa.pt
1008554JOP0010.1177/02698811211008554Journal of PsychopharmacologyTeixeira et al.
review-article2021
Review

Teixeira et al. 13
studies with psychedelics, with many encouraging outcomes
(Grinspoon, 1981; Grinspoon and Bakalar, 1979). Circa 1970,
psychedelic research was halted due to prohibitive new legisla-
tion with formidable barriers to research, inaccessibility of drug
product, a shifted public opinion, professional marginalization
and lack of funding (Bonson, 2018; Johnson et al., 2008).
The 21st century has witnessed a so-called ‘renaissance’ of
human research with psychedelic compounds. This is reflected
in mainstream coverage of the topic, advocacy movements (e.g.,
Mazzei, 2019) and improved funding for clinical research (e.g.,
Emerson et al., 2014; Nichols, 2014; Sessa, 2018). Research of
psychedelic-assisted psychotherapy has been published or is
now being planned or underway for a range of psychiatric condi-
tions including cancer-related distress (Gasser et al., 2014, 2015;
Griffiths et al., 2016; Grob et al., 2011; Ross et al., 2016),
depression (e.g., Carhart-Harris et al., 2021; National Library of
Medicine [NLM], 2017a, 2019b), anxiety (NLM, 2017b), sub-
stance use disorders (e.g., Bogenschutz et al., 2015; Johnson
et al., 2014; Moreno et al., 2006), obsessive compulsive disorder
(Moreno et al., 2006) and eating disorders (Carhart-Harris et al.,
2021). Despite mostly small-sample studies, published results
are largely promising (Johnson and Griffiths, 2017). In the USA,
the FDA has granted ‘Breakthrough Therapy Designation’ to
psilocybin therapy for depression for two separate sponsors,
effectively fast-tracking the development pathway to licensing if
clear criteria are met. The substances ketamine and MDMA
(3,4-methylenedioxymethamphetamine), which can induce psy-
chedelic-like effects, are also being studied for treating depres-
sion, posttraumatic stress disorder and substance abuse (e.g.,
Krediet et al., 2020). MDMA has also been granted Breakthrough
Therapy Designation by the US FDA for treating PTSD.
However, because ketamine and MDMA are not considered
‘classic psychedelics’ (their mechanisms of action only partially
overlap with those of psilocybin, LSD or DMT), they will not be
covered in this review.
How do psychedelics work? A
summary of neurobiological findings
Classic psychedelics are direct agonists at the serotonin
(5-hydroxytryptamine, or 5-HT) 2A receptor (5-HT2AR) sub-
type, and while all of the most popular psychedelics also have
activity at other receptor subtypes, agonism at the 5-HT2AR
appears to be key to their main action (Glennon et al., 1984;
Preller et al., 2017; Vollenweider, 1998; Winter et al., 2004).
Psychedelics have a favourable toxicity profile and therapeutic
index (Van Amsterdam et al., 2015), and apparently negligible
addiction potential (Rucker et al., 2018). The main hazards relate
to the intensity of the altered state of consciousness they produce,
particularly at higher doses, and the need for professional super-
vision under these conditions (Johnson et al., 2008).
The effect of stimulating the 5-HT2AR is to increase the post-
synaptic gain of the host neuron, which is commensurate with it
becoming more excitable to input. 5-HT2ARs are most densely
expressed on cortical layer V pyramidal neurons, important
information integration units (Jakab and Goldman-Rakic, 1998).
This increase in postsynaptic gain translates into a spike-wave
decoherence at the population level (Celada et al., 2008) and
increase in the complexity, unpredictability or entropy of field
potentials—an effect that correlates closely with the intensity of
subjective effects in humans (Schartner et al., 2017). Higher,
macroscopic level effects include the dysregulation of large-scale
intrinsic networks (Carhart-Harris et al., 2016), increase in the
repertoire of high-spatial frequency global brain states (Atasoy
et al., 2018), and an increase in the communication between
large-scale intrinsic networks (Carhart-Harris et al., 2016;
Tagliazucchi et al., 2016). At the anatomical level, psychedelics
have been found to promote cortical synaptogenesis, an impor-
tant marker of neuroplasticity (Ly et al., 2018). The pertinent
question, however, is: how do these effects relate to the putative
therapeutic action of psychedelic therapy?
Recently a model was introduced to directly address this
question (Carhart-Harris and Friston, 2019). It takes inspiration
from the hierarchical predictive processing model of global brain
function, which states that the brain strives to model its world in
order to minimize surprising exchanges with it and thus, promote
its mastery. Applied to psychedelics, the so-called ‘REBUS’
model, ‘relaxed beliefs under psychedelics’ states that psyche-
delics decrease the prediction-weighting of priors at different
levels of the brain’s functional hierarchy—but particularly its
highest hierarchical levels. In plainer language, this relates to
dysregulated activity in relevant dimensions of brain function
thought to encode high-level predictive models, such as the
strength of oscillatory rhythms (such as the predominant alpha
rhythm) and the integrity of intrinsic brain networks (such as the
default-mode network). In more intuitive experiential terms, this
effect relates to a felt relaxation of beliefs or assumptions e.g.,
about one’s self, relationships with others, or to the world more
generally. In many psychiatric disorders, it is argued that habits
of mind and behaviour, as well as beliefs, become ‘too precise’,
meaning they are rigidly encoded and too influential. Examples
include the negative cognitive bias in depression, specific crav-
ings in addictions, specific fears in anxiety disorders, specific
obsessions in obsessive compulsive disorder and specific bodily
beliefs in body image disorders. According to the REBUS model,
psychedelics afford the individual respite from weighty beliefs
and thus a window of opportunity for change that can be exploited
if combined with a commitment to therapeutic development
(Carhart-Harris, 2019).
The evidence presented above highlights a potentially rele-
vant link between the neuroscientific findings and behavioural
change which may be facilitated by psychedelics. Revision of
high-order mechanisms not only have an introspective conse-
quence (i.e., in affective and cognitive domains) but may also
result in exploratory behaviour which is consistent with new pat-
terns and beliefs acquired during or after the acute experience.
For example, a new appreciation for natural environments (Lyons
and Carhart-Harris, 2018) could result in an increase in nature
immersion behaviours (e.g., choosing parks or riverside trails to
be more physically active) or a more sustainable shopping and
dietary pattern. Such an increase in exploration of new behav-
iours would be consistent with an increase in the personality
domain called ‘openness to experience,’ which has been shown
to be increased by psilocybin (MacLean et al., 2011). From a
mechanistic point of view, evidence from psychology and neuro-
science experiments show that psychedelics are able to induce
flexible patterns of thinking in different cognitive domains,
which occur at a basic level of perception (Kometer et al., 2011;
Timmermann et al., 2018), as well as on domains related to

14 Journal of Psychopharmacology 36(1)
language and semantics (Family et al., 2016). Psychedelics may
also enhance creative thinking (Kuypers et al., 2016) during
acute states, depending on the context in which the experience
takes place (Hartogsohn, 2016). It is thus reasonable to assume
that the effects of psychedelics at multiple levels of the cognitive
hierarchy may result in long-term changes in behaviour.
Could psychedelic experiences
increase self-determination?
Self-determination, or perceived autonomy, can be defined as the
degree of self-endorsement of one’s actions at the highest order
of reflection (Ryan and Deci, 2006). Self-determined motivation
is consistently associated with improved psychological well-
being and with engagement with—and persistence in—a variety
of tasks and long-term behaviours (Ntoumanis et al., 2020).
Consequently, the concept has been explored in studies in health
behaviour change, in areas such as dental hygiene (Halvari et al.,
2019), diet, exercise and obesity (Teixeira et al., 2012a), diabetes
(Phillips and Guarnaccia, 2020) and tobacco cessation (Williams
et al., 2016), with generally encouraging results (Leblanc et al.,
2016; Sheeran et al., 2020; Teixeira et al., 2012b). We propose
that it could present a fruitful psychological framework from
which to understand how psychedelics could assist in lifestyle
change, especially from a motivational viewpoint.
According to self-determination theory (SDT; Ryan and Deci,
2017), at the root of self-determined motivation and behaviour is
the satisfaction of the three psychological needs of competence,
autonomy and relatedness (see Table 1 from Teixeira et al., 2020).
Much the same as the five human needs, as defined by Maslow,
may be necessary for human survival and development (Maslow,
1943), SDT posits that competence, autonomy and relatedness
are innate essential psychological needs for mental health and for
psychological growth. It suggests that human beings are naturally
inclined to ‘engage in interesting activities, to exercise capaci-
ties, to pursue connectedness in social groups, and to integrate
intrapsychic and interpersonal experiences into a relative unity’
(Deci and Ryan, 2000) but this will occur only to the extent basic
psychological needs are satisfied. SDT also makes reference to
the concept of ‘true’ or ‘core’ self,3 one which researchers and
practitioners involved with psychedelic therapy will easily relate
to many participants’ personal accounts (e.g., Noorani et al.,
2018; Watts et al., 2017).
We hypothesize that competence (akin to a sense of self-efficacy
and confidence in one’s capacities), autonomy (i.e., wholehearted
self-endorsement of one’s actions) and interpersonal relatedness
are all factors which psychedelics could plausibly influence.
Although at present we have no direct evidence for such effects,
accounts of participants in research trials for depression (Watts
et al., 2017), alcohol cessation (Nielson et al., 2018) and smoking
cessation (Noorani et al., 2018) suggest this could be the case.
Regarding competence, Nielson et al. (2018) included a category
of ‘confidence, motivation and resolve’ and another of ‘commit-
ment to change’ as descriptive of participants’ experiences. In
turn, Watts et al. (2017) reported feeling more ‘confident’, ‘resil-
ient’ and ‘effective’. In relation to ‘autonomy,’ Noorani et al.
(2018) found insights into self-identity (e.g., unveiling of true self,
and honesty with oneself) to result from sessions, and Watts et al.
(2017) reported increased connection to self and feeling more
attuned with ones’ internal needs and inherent worth as central
processes underlying transformative experiences, in previously
depressed patients (Watts et al., 2017). For example, ‘One of the
things that happened to me (...) was the magnification of how
important it was to be true to yourself and have integrity about it’
(Noorani et al., 2018: 11).
Finally, regarding relatedness, Noorani et al. (2018) noted that
sessions left participants with lasting impressions of intercon-
nectedness and an increase in prosocial behaviour. ‘Relatedness’,
as defined by SDT, is an especially interesting case vis à vis the
evidence that significant psychedelic experiences are often asso-
ciated with increased feelings of connectedness to others
(Carhart-Harris et al., 2018; Watts et al., 2017). A sense of unity,
which might be conceptualized as an ultimate level of related-
ness, is one of the features of the mystical experience construct
that is strongly affected by classic psychedelics (Johnson et al.,
2019). Future research will be needed to investigate whether psy-
chedelic experiences relate to changes in concepts central to SDT
(e.g., need satisfaction and autonomous self-regulation), and to
what extent these concepts may predict lasting behaviour change
after a positive experience or therapeutic process.
Spontaneous health behaviour
changes with psychedelics
As a result of these lessons [from psychedelic treatment for
depression], there were some major lifestyle changes; nearly half
Table 1. Conceptual definitions of the three psychological needs from self-determination theory.
Psychological need Conceptual definition
Autonomy The psychological need to experience self-direction and personal endorsement in the initiation and regulation of one’s
behaviour. The hallmarks of autonomy need satisfaction are volitional action and wholehearted self-endorsement (i.e.,
personal ownership) of that action.
Competence The psychological need to be effective in one’s interactions with the environment. It reflects the desire to extend one’s
capacities and skills and, in doing so, to seek out optimal challenges, take them on, and exert effort and strategic thinking
until personal growth is experienced.
Relatedness The psychological need to establish close emotional bonds and attachments with other people. It reflects the desire to be
emotionally connected to and interpersonally involved in warm relationships. The hallmarks of relatedness need satisfaction
are feeling socially connected and being actively engaged in both the giving and receiving of care and benevolence to the
significant people in one’s life.
Conceptual definitions are based on Ryan and Deci (2017).

Teixeira et al. 15
of the sample reported improvements to diet, exercise, and cut-
ting down on drinking alcohol. One described the improvement
to his diet that happened after the dose as ‘life-changing’,
although he was not sure how these changes came about as he
did not receive direct ‘lessons’ about diet. (Watts et al., 2017: 13)
To our knowledge, no study has been conducted specifically
to investigate lifestyle behaviours such as over-eating and physi-
cal activity in relation to psychedelic use. However, some studies
have asked participants to report spontaneous changes in various
areas of their lives, including in health behaviours, perhaps due to
the fact that anecdotal accounts of these phenomena are not
uncommon. In fact, it appears that the first studies in alcohol
abuse were initiated precisely because of ad hoc observations by
some users – notably Leo Zeff, a famous psychedelic clinician,
regarding his own smoking cessation success after using a classic
psychedelic (c.f. Johnson et al., 2017b). It is also interesting to
note that, along with environmental concerns, healthy eating and
living more healthfully were popular elements of psychedelic
culture from the beginning, at least in some communities (Smith
and Sternfield, 1970).
In a recent observational study, 380 ayahuasca users were
interviewed face to face and asked about their health (including
height and weight, allowing for calculation of their body mass
index (BMI)) and also their physical activity, diet and yoga/medi-
tation habits (Ona et al., 2019). These measures were then com-
pared to data from the general population. Although limited by
the cross-sectional nature of the data (e.g., confounding factors
may be present), results showed that ayahuasca users had a mean
BMI of 22.6 kg/m2, well below the 30 kg/m2 cut-off for obesity
and clearly lower than that of the general Spanish population
(around 26 kg/m2 in 2016; World Health Organization, 2017a)
and had a high fruit and vegetable consumption (60–75% ingest-
ing 3–6 servings a day of each vs. 22–48% in the general popula-
tion). As to physical activity, 55% reported being ‘as physically
active as they wished’, a value that seems high but which cannot
be compared with any standard measure of activity in the popula-
tion (Ona et al., 2019).
In a US survey of 343 people who claimed to have stopped or
reduced alcohol consumption and misuse after a psychedelic
experience, 63% of the participants also endorsed ‘improved
diet,’ and 55% reported ‘increased exercise’ as a result of their
psychedelic experience (Garcia-Romeu et al., 2019b). In a simi-
lar study of 444 participants who claimed to have stopped or
reduced cannabis, opioid or stimulant misuse after a psychedelic
experience, 59% endorsed ‘improved diet’ and 58% endorsed
‘increased exercise’ as a result of their psychedelic experience
(Garcia-Romeu et al., 2019a). It is unknown from these studies
whether these individuals were intentionally seeking changes in
these specific areas as they embarked on psychedelic use.
However, one can speculate that many were probably not because
only 9.9% reported an intention to reduce/quit drinking alcohol.
This suggests that psychedelic-assisted interventions that more
specifically target health behaviour changes could result in even
higher rates of success in this domain.
The Johns Hopkins’ studies on smoking cessation also pro-
vide some evidence that participants were making other positive
changes in their lives (besides reducing smoking) as they went
through the psilocybin-assisted therapy programme. Both the ini-
tial (Johnson et al., 2014) and follow-up (Johnson et al., 2017a)
studies report significant (51%) increases in a self-reported scale
titled ‘positive behaviour changes’ as people moved from base-
line to the end of the treatment. These were described further in a
qualitative analysis, which reported increases in time spent in
nature, taking time for oneself, prosocial behaviours such as vol-
unteering and joining community groups, and greater engage-
ment with art (Noorani et al., 2018). A similar pattern was
observed in the study of psilocybin for depression in cancer
patients, from the same research group (Griffiths et al., 2016).
Although these are not health-related behaviours per se, results
suggest psychedelics may be associated with life changes con-
sistent with improved well-being and meaning. In support of this,
a recent 4.5 year follow-up of cancer patients who underwent
psilocybin-assisted therapy showed persisting increases in not
just well-being/life satisfaction (reported by 86% of participants,
n=12) but also in ‘positive behaviour changes’ attributed to the
psilocybin experience (100% of participants, n=14) (Agin-Liebes
et al., 2020).
A qualitative descriptive study with 16 participants who had
been previously diagnosed with an eating disorder (ED, anorexia
nervosa or bulimia nervosa) and were at various phases of illness
and/or recovery investigated how having partaken in one or sev-
eral ayahuasca ceremonies influenced their management of their
condition or recovery process (Lafrance et al., 2017). A majority
of participants reported reductions in ED-related negative
thoughts, improvements in emotional processing and regulation,
and an increased ability to identify what they perceived as the
root psychological causes of the disorder. No specific behav-
ioural changes were measured, but participants generally either
reported more easily managing symptoms or having achieved
full and sustained remission, subsequent to their psychedelic
experience.
Finally, a recent study looked at benefits and challenges in
278 users of microdosing with LSD and/or psilocybin (Anderson
et al., 2019). Microdosing typically involves the regular (i.e., 2–3
times a week) intake of about 5–15% of the normal dose used in
most studies. Consequently, both the brain/neurological effects
as well as the psychological (and phenomenological) effects with
this dosing model are presumed to be partially different than
those from taking a high dose (Passie, 2019). These differences
notwithstanding, and also considering other limitations (self-
selected convenience sample with no comparison group), micro-
dosing was associated with spontaneous improvements in
meditative practice (49.1% of participants), exercise (49.1%),
eating habits (36.0%) and sleep (28.8%); and with reduced use of
caffeine (44.2%), alcohol (42.3%) and tobacco (21.0%).
From addiction to behaviour change
interventions using psychedelics
Among the mental health/psychiatric targets of early clinical psy-
chedelic research in the 1950s and 60s were disorders primarily
defined by behavioural problems, including substance abuse dis-
orders (e.g., alcohol, opioids). Surveying studies from the 1950s
to 1970s, a meta-analysis of six double-blind intervention studies
using LSD for alcohol misuse suggested a significant effect in
abstinence rates at the short (2–3 months) and the medium-term
(6 months), but not at 12 months (Krebs and Johansen, 2013).
This line of research was resumed more recently, and results have
tended to confirm the earlier observations with psilocybin for

16 Journal of Psychopharmacology 36(1)
alcohol dependence (Bogenschutz et al., 2015), and extended it
to tobacco smoking (Johnson et al., 2014, 2017b). In the latter
studies, after two or three drug sessions and behaviour therapy
before and after, biologically verified smoking abstinence at
12 months and ~30 months by far surpassed success rates in cur-
rent treatment modalities (Johnson et al., 2017a). A complemen-
tary survey describes instances in which classic psychedelic use
outside of research settings is followed by cessation or reduction
of tobacco smoking (Johnson et al., 2017b).
Mechanisms of action in tobacco cessation with psychedelics
reportedly include improved mood and affect, change in life pri-
orities and values, motivational insights and emotional regulation
(Johnson et al., 2017b). In addition, qualitative analysis of smok-
ing cessation participants suggested psilocybin sessions helped in
smoking abstinence by providing insights into self-identify and
personal reasons for smoking, a sense of awe, curiosity and inter-
connectedness, and a persistent overshadowing of withdrawal
symptoms (Noorani et al., 2018). It is noteworthy that for both
smoking and alcohol dependence the most recent intervention tri-
als using psychedelics have employed mainstream motivational/
behaviour change methods such as Motivational Interviewing
(Nielson et al., 2018) and Cognitive Behavioural Therapy
(Johnson et al., 2014) to complement the substance-induced psy-
chedelic experience(s). Both Motivational Interviewing and
Cognitive Behavioural Therapy have been used extensively in
the areas of mental health and health behaviour change (e.g.,
Frost et al., 2018; Health Quality Ontario, 2019).
The models of psychedelic therapy which are now emerging
in the field (e.g., Watts and Luoma, 2020; Wolff et al., 2020) typi-
cally include one or two sessions where participants ingest the
psychedelic compound (e.g., a psilocybin capsule), with variable
amounts of preparation and integration therapeutic sessions
(Johnson et al., 2008). Trained guides/therapists are usually pre-
sent for the duration of the psychedelic experience. One refer-
ence is the use of psilocybin for smoking cessation at Johns
Hopkins (Johnson et al., 2014, 2017a), where participants under-
went a 15-week programme with six preparation/integration indi-
vidual meetings. Psychedelic-assisted behavioural change
interventions could also take place in a group format, which is
often used in ceremonial settings, and holds much promise as a
cost-effective way to deliver psilocybin therapy in research con-
texts. Although current lifestyle behaviour change interventions
(e.g., for weight loss or diabetes) involve a wide variability of
formats and length, a programme of several weeks (sometimes
months) with regular educational sessions in a group setting is a
very common model (e.g., Teixeira et al., 2010).
Looking forward, the therapeutic container for such work
could be the ACE model (Accept, Connect, Embody) which was
used to support patients undergoing psilocybin treatment for
depression (Watts and Luoma, 2020) and is based on Acceptance
and Commitment Therapy or ACT (A-Tjak et al., 2015). In fact,
Walsh and Thiessen (2018) have also proposed that psychedelic
therapy should incorporate Acceptance and Commitment
Therapy, a framework which has also been used for different
mental and physical health problems, including obesity (Lawlor
et al., 2020) and depression (Bai et al., 2020). Alternatively, as
highlighted above, Cognitive Behavioural Therapy (see also
Wolff et al., 2020) and Motivational Enhancement Therapy
(including Motivational Interviewing) could be used as therapeu-
tic containers, as each of these has been supported by robust
research as effective in supporting multiple varieties of health
behaviour change (Miller and Rollnick, 2012). Motivational
Interviewing in particular is largely consistent with SDT (Patrick
and Williams, 2012), and both have a range of intervention tech-
niques (e.g., Teixeira et al., 2020) which could be tested as part of
future psychedelic-assisted behaviour change interventions.
Final considerations
We have reviewed the modern resurgence in psychedelic
research with a focus on therapeutic applications. Among these
are the treatment of addictions (alcohol and tobacco) using
psychedelics, which can be viewed as instances of health
behaviour change facilitation. We have also briefly reviewed
how biological effects of psychedelics may result in acute psy-
chological effects, such as relaxed beliefs, that may have long-
lasting effects on perspective and behaviour. In addition, we
have proposed that SDT, which emphasizes autonomy, compe-
tence and relatedness, may be a useful framework to understand
increases in internally driven motivation upon well-integrated
psychedelic experiences. Finally, we propose directions for
how psychedelic work in behaviour change may be conducted
in the future, establishing several parallels between commonly
used models, such as Cognitive Behavioural Therapy or
Acceptance and Commitment Therapy, and emerging psyche-
delic-assisted therapies for tobacco cessation or depression
(e.g., the ACE model). Another area for future enquiry is to
examine the role of individual differences in suggestibility as
well as drug-induced enhancements of suggestibility in moder-
ating and mediating behavioural change (Carhart-Harris et al.,
2015; Carhart-Harris and Friston, 2019).
One concern might be an impression by some in the public
that administering psychedelics to patients might cause them to
lose motivation for prior pursuits and for engagement in main-
stream society, including abandonment of family responsibilities.
We suspect such fears are driven not by the pharmacological
effects of psychedelic drugs, but by their historical cultural asso-
ciation with the counterculture and their status as illicit drugs.
The data that directly addresses these questions in clinical
research do not show evidence for it. For example, Griffiths et al.
(2006, 2011) examined ratings by community observers (i.e.,
family members, friends or co-workers with frequent contact
with the participant) about the participant’s behaviours, attitudes
and functioning. These were assessed before psilocybin adminis-
tration and up to 2 or 14 months after psilocybin administration.
Both studies showed significant long-term improvements as
assessed by these community observers, suggesting that the inter-
vention did not cause a general tendency for people to drop out of
mainstream society or disengage with their families. The clinical
studies reviewed have utilized preparation, monitoring and some
form of integration (Johnson et al., 2008). As psychedelics move
forward as possible approved therapeutics, to minimize the
potential for societally disruptive effects it is important that clini-
cians observe appropriate clinical practice boundaries and not
introduce counter-cultural or supernatural frameworks to patients
in the context of psychedelic therapy (Johnson, 2020).
There are numerous future directions suggested by our frame-
work. Studies should expand existing research to look at broader
ranges of behavioural targets including diet, exercise and other

Teixeira et al. 17
‘wellness behaviours’. If such research endeavours are also
encouraging, this would further reinforce the already suggestive
case that psychedelic therapy can be broadly applicable to behav-
iour change via transdiagnostic mechanisms. Future work should
continue to conduct hypothesis-driven tests of the REBUS and
other models that may be useful for bridging our understanding of
how acute pharmacological effects translate into long-term behav-
iour changes. Empirical work should also address the role of ther-
apy, for example, whether results are enhanced when psychedelic
sessions are accompanied by explicit frameworks such as
Cognitive Behavioural Therapy, Motivational Interviewing and
the ACE model, versus psychedelic sessions with only general
preparation, monitoring and follow-up discussion. Additionally,
research should eventually compare these, and potentially other
therapeutic models, in their ability to support psychedelic therapy
for particular indications. From the broadest perspective, if psy-
chedelic-assisted therapy is found to work through general pro-
cesses, such as relaxed beliefs, psychological flexibility and
self-determined motivation, this might be used to enhance behav-
iour change across a number of disorders and lifestyle challenges,
and enhance the effects of multiple psychotherapeutic approaches.
This would constitute a shift to a fuller transdiagnostic under-
standing of psychiatric disorders along a continuum with norma-
tive human behaviour and lifestyle challenges.
Declaration of conflicting interests
PJT is the research director at The Synthesis Institute B.V.. MWJ is an
advisor to AWAKN Life Sciences Inc., Beckley Psytech Ltd., Entheogen
Biomedical Corp., Field Trip Psychedelics Inc., Mind Medicine Inc.,
Otsuka Pharmaceutical Development & Commercialization Inc., and Silo
Pharma, Inc.; CT is an advisor for Entheon Biomedical Corp; RW is a
member of the Clinical Advisory Board of the Usona Institute; and clini-
cal director at The Synthesis Institute B.V.. DE is an advisor for Field Trip
Psychedelics Inc. and Mydecine Innovations Group Inc. HD was funded
by the Imperial College London President’s PhD Scholarships. RCH is a
scientific advisor for Entheon Biomedical Corp., Mydecine Innovations
Group Inc., The Synthesis Institute B.V., Usona Institute, Beckley
Psychtech Ltd., Maya PBC, Osmind PBC, and TRYP Therapeutics Inc.
HK declared no potential conflicts of interest with respect to the research,
authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the
research, authorship, and/or publication of this article: PJT was partially
funded by Fundação para a Ciência e Tecnologia, under Grant
UIDB/00447/2020 to CIPER. All other authors received no financial sup-
port for the research, authorship, and/or publication of this article.
ORCID iDs
Pedro J Teixeira https://orcid.org/0000-0001-7202-0527
David Erritzoe https://orcid.org/0000-0002-7022-6211
Hannes Kettner https://orcid.org/0000-0001-9482-0998
Robin L Carhart-Harris https://orcid.org/0000-0002-6062-7150
Notes
1. The word ‘psychedelic’ is derived from the Greek meaning
‘mind manifesting’ or ‘mind revealing’.
2. A drink traditionally produced and used ceremonially in
South America, but also used by churches in North America
and Europe. It is commonly made from a combination of
the Banisteriopsis caapi vine with one of several DMT-
containing plants (such as Psychotria viridis) (Ott, 1996).
3. See Ryan and Deci (2017) for an in-depth discussion of this
concept and its historical use in Psychology and Philosophy.
In brief, it is conceived within the ‘self-as-process’ tradition
as an innate, integrative, organizing ‘energy’ (motivational
force) directed towards the realization of one’s potentials
and full functioning, or eudaimonia. It is associated with the
expression of integrity, spontaneity and vitality, and with a
sense of ‘feeling real’, unmasked, ‘true to heart’, and with
access and sensitivity to one’s feelings and needs.
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