Abstract
Rising international migration, paired with increasing public support for far-right political parties, poses a growing challenge to the countries tasked with successfully integrating immigrants into their society. Further complicating this matter is the fact that the acculturation process which immigrants undergo to fully integrate into their host society can be long, difficult, and taxing to their mental health, physical health, and sense of belonging. A better understanding of how the unique burdens faced by immigrants might be alleviated or more easily processed is therefore vital for the success of both immigrants and their host countries. Drawing on initial findings suggesting that classic psychedelics can help individuals process incidents of discrimination, make healthier decisions, and experience deeper feelings of connectedness to others, this literature review presents a roadmap for determining what classic psychedelics may offer immigrants, a large and rapidly growing international minority group.
Introduction
International migration has been increasing for decades and in 2019 an estimated 272 million people were living outside their country of birth (McAuliffe et al., 2019). The continued and effective integration of these individuals into their host countries is a grand challenge for many countries (George et al., 2016) given that this trend is expected to increase with the worsening of the climate crisis (Burke et al., 2015). As climate-driven conflict and violence escalate, and more regions become uninhabitable to humans, the number of migrants worldwide is predicted to reach 405 million by 2050 (Koser and Laczko, 2010).
Complicating the issue of rising migration is the fact that it, or simply the fear thereof, commonly generates local support for far-right political parties (Halikiopoulou and Vlandas, 2020; Halla et al., 2017) as negative attitudes towards immigration are often the primary motivation of far-right supporters (Arzheimer and Berning, 2019; Swyngedouw, 2001). Unfortunately, and insidiously, the mere presence of far-right parties has been reported to have spillover effects on other political parties, negatively biasing their opinions of immigrants (Schilling and Stillman, 2022). Xenophobic political rhetoric presenting immigrants as threatening outsiders has been associated with greater anti-immigrant attitudes in the general population (Bohman, 2011) as well as the mobilization of those with such sentiments (Flores, 2017). It is therefore no surprise that immigrants are often the targets of discrimination by natives in their host country (Arici et al., 2019; Sterud et al., 2018).
Discrimination by natives of their host country can hinder immigrants’ acculturation, the process by which they adapt to their host countries’ culture (Berry, 1992). This is because experiences of rejection are mentally and physically taxing to those targeted, and can threaten their sense of belonging (for a review, see Esses, 2021). As a result, discrimination can hinder immigrants’ development of positive relationships with natives, and, with it, their mastery of the native language and other valuable cultural skills, thereby threatening their successful integration into their host country (Verkuyten and Yildiz, 2007).
Recent work in the budding field of psychedelic research, however, suggests that classic psychedelics may help targeted minority groups (i.e. immigrants) better process and respond to discrimination, as well as use these challenging experiences as a chance for personal growth (Ching et al., 2022; Haeny et al., 2023; Williams et al., 2020; De la Salle et al., 2022). Classic psychedelics are serotonin 2A receptor (5-HT2AR) agonists that can alter individuals’ perceptions, moods, and cognitive processes (Nichols, 2016). They include lysergic acid diethylamide (LSD), mescaline (the active ingredient in the peyote and San Pedro cacti), psilocybin (“magic mushrooms”), and N,N-Dimethyltryptamine (DMT), all of which are heavily controlled (Schedule I) substances whose possession is a criminal offence in the United States (U.S.), United Kingdom, and many other Western countries (United States Drug Enforcement Administration, n.d.; European Monitoring Centre for Drugs and Drug Addiction, n.d.; Home Office, 2022).
Beyond the need driven by rising international migration and public support for far-right political parties, investigations of how classic psychedelics affect immigrants is becoming increasingly important as the use of these substances becomes more common. For example, the U.S. states of Oregon and Colorado recently legalized the use of psilocybin, and other U.S. states have begun proposing similar bills (Jacobs, 2023; Jefferies, 2022). In Australia and the Canadian province of Alberta, recent policy changes now allow psilocybin to be legally prescribed by psychiatrists (Chrysanthos and Dow, 2023; Dyck, 2023). Moreover, the prevalence of classic psychedelic use in the U.S. general population has grown in recent years (Walsh et al., 2022; Yockey and King, 2021) and past year use of LSD and psilocybin is currently estimated at around 4% in some European countries (e.g. 3.8% in Austria and 5.3% in Czechia; European Monitoring Centre for Drugs and Drug Addiction, 2022). Motivated by these continuing developments, this literature review summarizes how immigrants’ mental health, physical health, and sense of belonging are taxed during the acculturation process, introduces classic psychedelics as a potential means of mitigating these negative outcomes, and discusses a path forward for research on this topic. In doing so, it aims to inform the current discussion regarding what these substances can offer and to whom.
Acculturation and immigrants’ mental health
Discrimination based on one's immigrant status or country of origin is linked to an array of negative mental health outcomes including psychological distress and depressive symptoms (Szaflarski and Bauldry, 2019; Agudelo-Suárez et al., 2011). This has been found to be the case for an array of different immigrant groups including refugees, expatriates, and international students (Afsharian et al., 2021; Dos Santos, 2020; Lee and Rice, 2007). The negative impact of discrimination on immigrants is particularly harmful given that immigrants have been found to access mental health services at a lower rate than natives despite their greater need (for a review, see Derr, 2016). Thus, research on how immigrants’ mental health and well-being can be effectively supported is especially important (Noh et al., 2007). Instead of accessing mental health services, immigrants may instead opt to self-medicate and having immigrant status has indeed been associated with greater amounts of self-reported self-medication (Carrasco-Garrido et al., 2010). This is despite the fact that self-medication can involve illegal (or dangerous) activity, such as illegally acquiring prescription medication or consuming banned substances (Coffman et al., 2008; Pylypa, 2001).
One group of largely illegal substances used for self-medicative purposes are classic psychedelics (Kopra et al., 2023). This is unsurprising given that classic psychedelics have been shown in a growing number of studies to be both safe and effective at treating various mental health conditions including anxiety, trauma, and treatment-resistant depression (for a series of reviews, see Winkelman and Sessa, 2019). In cross-sectional studies of the U.S. general population, lifetime classic psychedelic use (i.e. any prior use of a classic psychedelic) has been associated with lower odds of mental health problems (e.g. psychological distress, suicidality; Hendricks et al., 2015; Krebs and Johansen, 2013) which may explain why individuals with lifetime classic psychedelic use report taking fewer days of sick leave from work than those without (Mellner et al., 2022).
Specific to the mental health of oft-targeted victims of discrimination (i.e. immigrants), recent cross-sectional, retrospective studies have associated psychedelic use with better mental health outcomes (e.g. decreased anxiety, feelings of isolation, or concerns of future discrimination) following racial trauma in black, indigenous, and people of color (Ching et al., 2022; Haeny et al., 2023; Walsh et al., 2022; De la Salle et al., 2022). Initial findings suggest that psychedelic experiences positively impact victims of discrimination by increasing their psychological flexibility (Davis et al., 2021; Haeny et al., 2023), a fundamental aspect of mental health characterized by one's ability to manage stress and respond with adaptive behaviors (Kashdan and Rottenberg, 2010). The replicable findings that classic psychedelic use is associated with more positive mental health outcomes following racial trauma are intriguing given that a cross-sectional study on the U.S. general population reported lifetime psilocybin use to be associated with lower odds of psychological distress and suicidal ideation in whites, but not in black, indigenous, or multiracial individuals (Jones and Nock, 2022). Nonetheless, additional, albeit indirect, support for the idea that classic psychedelics have the potential to help immigrants deal with acculturative stressors like discrimination comes from two cross-sectional studies conducted in the midst of the Covid-19 pandemic. A two-part survey study conducted in Argentina on lifetime psychedelic use associated it with “enhanced resilience and well-being in the light of challenging situations” (Cavanna et al., 2021; p.91). Similarly, a transcultural study conducted primarily in Spain and Brazil exploring regular psychedelic use during this period showed classic psychedelic use to be associated with less psychological distress, causing the authors to allude to a protective factor offered by psychedelics during stressful events (Révész et al., 2021). Based on these initial correlational findings, prior classic psychedelic use may be able to help immigrants in dealing with later experiences of discrimination.
The continued negative impact on mental health resulting from prior experiences of discrimination may also be alleviated by later use of classic psychedelics. Experimental support for this idea comes from three studies, each with a small sample size, showing that a single, high dose of psilocybin or LSD can have long-lasting positive effects on healthy users’ mood and attitudes towards life (Griffiths et al., 2011, 2018; Schmid and Liechti, 2018). Furthermore, studies implementing neuroimaging have found that a single dose of psilocybin decreases amygdala reactivity to negative stimuli (Kraehenmann et al., 2016) and changes in the neural correlates of affective processing following psilocybin use can persist for weeks in healthy individuals (Barrett et al., 2020). Psilocybin use may therefore ease immigrants’ acculturation by limiting their sensitivity to devaluing cues (e.g. discriminatory remarks or symbols) in their new environment. Like racial discrimination, the discrimination faced by immigrants is often based on their race (i.e. physical characteristics) or ethnicity (i.e. culture) (Chung and Epstein, 2014). Thus, any beneficial effects of classic psychedelics on racial trauma may also be applicable to the discrimination and traumata experienced by immigrants.
Acculturation and immigrants’ physical health
In addition to investigations on classic psychedelics’ potential ability to mitigate the negative mental health effects of discrimination, future studies should also investigate whether classic psychedelic use promotes immigrants’ physical health during their acculturation process. This is important since non-Western immigrants who immigrate to Western countries such as the U.S., Canada, or Australia commonly have better physical health and lower mortality rates compared to their native-born counterparts at entry (for a review, see Markides and Rote, 2015). This health advantage, termed the “immigrant health paradox”, declines with the number of years these individuals reside in their host country (Markides and Rote, 2015). One reason for this is the detrimental change in these immigrants’ diet which occurs when they switch to a Western diet comprised largely of salt-, fat-, and sugar-laden foods (Antecol and Bedard, 2006). However, recent work hints that immigrants’ negative health trajectory during the acculturation process could be mitigated with classic psychedelic use. For example, large-scale (albeit cross-sectional) studies in the U.S. general population have linked lifetime classic psychedelic use with lower odds of physical health problems (e.g. obesity, hypertension; Simonsson et al., 2021a, 2021b) and recent theorizing has proposed that psychedelics may help promote healthy behaviors regarding diet, exercise and stress reduction by increasing individuals’ self-determination (Teixeira et al., 2022). Furthermore, classic psychedelic use in the general population has been associated with diet-related behaviors (Harris and Gurel, 2012; Simonsson et al., 2022), as well as smoking cessation (Daldegan-Bueno et al., 2022; Johnson et al., 2017) and alcohol cessation (Agin-Liebes et al., 2021b; Garcia-Romeu et al., 2019). Similarly, a recent cross-sectional study focusing specifically on ethnic and racial minorities in the U.S. found classic psychedelic use to be associated with reduced drug and alcohol use (Haeny et al., 2023). These findings suggest that classic psychedelic use may help immigrants with high levels of physical health maintain this during the acculturation process, and immigrants with low levels of physical health take measures to change this.
It is also important to note that mental health and physical health are intimately entwined (Ohrnberger et al., 2017), with mental health capable of predicting later health-related behaviors (e.g. alcohol and nicotine consumption; Bandiera et al., 2017; Virtanen et al., 2015). As such, the potential positive effects of classic psychedelic use on immigrants’ mental health already discussed may, in turn, contribute to their physical health. However, literature on if, and how, classic psychedelic use affects physical health via mental health is lacking. This could be a fruitful path to pursue given scholars’ recent theorizing on the use of classic psychedelics to treat obesity (Fadahunsi et al., 2022; Reichelt, 2022), a growing issue linked to mental health (Avila et al., 2015) and faced by certain immigrant groups (Kaplan et al., 2004). Although much more research is needed to establish whether classic psychedelic use is reliably and causally linked to physical health outcomes (and by which mechanisms), initial work suggests that classic psychedelic use may promote certain behaviors related to physical health.
Acculturation and immigrants’ sense of belonging
The acculturation process can be long and difficult, with the most difficult aspect said to be the lack of a sense of belonging that immigrants can experience in their host country (Berry et al., 1987; Mena et al., 1987). Immigrants’ self-identification with natives in their host country, also referred to as their host national identity (Fuller-Rowell et al., 2012), is an affective aspect of their acculturation experience (Schwartz et al., 2011) associated with the fundamental human need to belong (Ellemers et al., 2002). It plays an important role in the integration process and is linked to a diverse array of important outcomes including immigrants’ well-being, educational attainment, drive to adapt to their host country, and even the extent to which they make (sub)optimal financial decisions (Hang and Zhong, 2022; Janke et al., 2023; Phinney et al., 2001). From a broader perspective, immigrants’ host national identity has been considered of particular import to host countries because a sense of shared national identity is believed to be required for a well-functioning society (Parekh, 2000).
Perceived similarity is a precursor to liking and a sense of connection with others (Hampton et al., 2018; McPherson et al., 2001), so when immigrants cannot identity with their host country or host country nationals, they lose the motivation to interact with their native counterparts (Di Saint Pierre et al., 2015; Froehlich et al., 2022). Of course, it is not surprising that individuals prefer to socialize with members of their own ingroup (Mehra et al., 1998) but a preference for non-native relationships can limit immigrants’ language proficiency which is vital for their social and cultural integration (De Vroome et al., 2014). Importantly, contact with natives can help immigrants acquire valuable cultural skills (Aycan and Berry, 1996) which, in turn, can significantly boost their earning potential in the labor market (Tammaru et al., 2010). Without the social support or financial advantages that come with having ties to host country natives, immigrants likely experience a lonelier, more difficult, and less successful acculturation process.
Use of classic psychedelics (particularly psilocybin), however, has been associated with long-lasting changes in socially-oriented aspects of personality including openness, extraversion, and connectedness (Agin-Liebes et al., 2021a; Erritzoe et al., 2018; Forstmann et al., 2020; MacLean et al., 2011), the sense that one is connected to the self, others, and the world more generally (Watts et al., 2017). These findings suggest that classic psychedelics promote changes in users which could help them to socialize with others (e.g. natives). Immigrants who have used classic psychedelics may, as a result, be better able to identify, and more motivated to form meaningful relationships, with natives in their host country. Increased feelings of connectedness as a result of classic psychedelic use may help also immigrants maintain the relationships they already have, whether that be with friends and family still living in their country of origin or new relationships formed since their arrival. By strengthening these bonds, and supporting the development of new ones, the increased sense of connectedness stemming from psychedelic experiences may offer immigrants a buffer to the socioemotional challenges commonly faced during the acculturation process.
The deep personal insights frequently reported as gained during psychedelic experiences (e.g. Peill et al., 2022) may also help protect immigrants’ self-esteem, which can be negatively affected during the acculturation process. For example, discrimination, a lack of fluency in the native language, and a lack of recognition for credentials earned in one's country of origin can all decrease one's sense of self-esteem (Lopez and Shen, 2020; Liu and Wang, 2012; Nesdale and Mak, 2003). This is important considering that self-esteem and social behavior are associated, with individuals with low self-esteem having more difficulty in, and deriving less pleasure from, social interactions (Helmreich and Stapp, 1974). Recent findings from randomized clinical studies show, however, that a single high dose of psilocybin can have positive effects on healthy individuals’ attitudes about themselves six months after receiving the dose (Griffiths et al., 2011, 2018). By increasing individuals’ sense of self (i.e. self-esteem) and promoting social behavior (e.g. approaching others rather than waiting to be approached), classic psychedelics may motivate social behaviors in immigrants that can simultaneously increase their sense of connectedness to, and belonging in, their host country.
Acculturation from the perspective of host country natives
Although the focal group of this literature review are immigrants and not their native counterparts, it is also worth mentioning that the increased connectedness arising from classic psychedelic use could potentially decrease anti-immigrant discrimination by humanizing perpetrators’ perceptions of their immigrant victims. Support for this idea comes from a randomized trial involving psilocybin in which healthy participants reported being more accepting and empathic, as well as less judgmental of others, up to 14 months after receiving their dose (Griffiths et al., 2011). Furthermore, and regarding the topic of immigration more generally, a qualitative study investigating psilocybin in depressed patients reported that “four patients described having powerful insights about the European refugee crisis during the dose, which was unexpected and uncharacteristic of them” (Watts et al., 2017, pg. 15). It is therefore unsurprising that psychedelics are thought to increase social tolerance and cohesion (Rodríguez Arce and Winkelman, 2021). Cross-sectional population studies support this view by showing that lifetime classic psychedelic use is inversely associated with various forms of aggressive behavior (Hendricks et al., 2018; Thiessen et al., 2018).
Furthermore, two cross-sectional studies reported a negative correlation between classic psychedelic use and conservatism (Forstmann and Sagioglou, 2017; Nour et al., 2017), which is associated with more negative views of immigrants (Haubert and Fussell, 2006). That being said, the association between classic psychedelic use and conservatism has been contested based on a shortage of evidence (Johnson and Yaden, 2020) and it has instead been argued that classic psychedelics are “politically pluripotent” with the potential to amplify both liberal and conservative beliefs depending on contextual factors (Pace and Devenot, 2021). As such, sound empirical studies investigating the role of contextual moderators are needed to determine if, and when, classic psychedelic use can (positively) influence natives’ perceptions of immigrants.
Finally, use of classic psychedelics has been associated with long-term changes in personality, including decreases in maladaptive narcissism (Van Mulukom et al., 2020), and, as already mentioned, increases in openness (for a review see Knudsen, 2022). Furthermore, changes in neuroticism have been reported up to three months following ceremonial consumption of the DMT-containing brew ayahuasca (Weiss et al., 2020). Thus, these findings suggest that classic psychedelics could potentially reduce natives’ perceptions of both their superiority over immigrants and immigrants as threatening outsiders (Schnieders and Gore, 2011; Widiger, 2009) by altering their psychological traits. Further research is needed here, however, as self-reported and observer-rated changes in personality following classic psychedelic use do not always align (Weiss et al., 2020; see also Smigielski et al., 2019). Furthermore, pre-drug differences that predict classic psychedelic drug use (e.g. risk taking) represent third variables that may explain personality changes in users over time, as well as fixed personality differences between users and non-users. Therefore, caution is warranted when interpreting studies investigating classic psychedelic and personality. Based on the outcomes of these initial, albeit tenuous findings, how classic psychedelics shape locals’ perceptions of immigrants could make for an informative and timely topic of study especially considering that, according to Gordon (1964), a willing immigrant cannot successfully assimilate into a host country whose native population is unreceptive to immigrants.
Caution, current limitations, and a way forward
It is important to note that, although this literature review advocates for the study of classic psychedelic use in immigrant groups, it does not advocate for widespread classic psychedelic use as a means of easing one's acculturation process. This is because for immigrants, as with other minority groups (Neitzke-Spruill, 2019), it can be uniquely difficult to find the proper set and setting in which to use these substances. Set and setting refer to the “psychological, social, and cultural parameters which shape the response to psychedelic drugs” (Hartogsohn, 2017, pg. 1) and they are vital for psychedelic experiences to have safe and positive outcomes (Haijen et al., 2018; Schlag et al., 2022). As already discussed, immigrants are at particular risk of having mental health issues and lacking a sense of belonging (i.e. being in an unfavorable mindset), as well as experiencing discrimination (i.e. being in an unfavorable setting). Thus, unguided use of classic psychedelics, even in “micro” doses (Hutten et al., 2019), could have unintended, negative psychological and physiological consequences for these individuals (Kopra et al., 2022a, 2022b).
Furthermore, classic psychedelics are largely illegal (Schedule I) substances and being caught with them could have disastrous financial and legal consequences for immigrants, including threatening their right to stay in their host country. This could be a limiting factor for research on classic psychedelic use in immigrant groups, as these individuals are likely particularly wary of disclosing any illegal behavior to researchers. Furthermore, given the myriad (and time-consuming) challenges that come with integrating into one's host country, recruiting immigrant study participants can be a difficult undertaking (Harrison et al., 2018; Lopez-Class et al., 2015).
In addition to factors that may limit future studies on classic psychedelic use in immigrant groups, consideration must also be given to the limitations of existent studies on which future research will need to build. Currently, the majority of field studies’ investigating associations between classic psychedelic use and mental health, physical health, or the processing of discrimination-based trauma are reliant on cross-sectional designs and North American study samples. This makes it impossible to draw causal conclusions from these studies and severely limits the external validity of their findings to other, psychedelic-experienced populations. Studies utilizing experimental or longitudinal designs in alternative geographic regions are therefore needed to determine: (a) whether classic psychedelic use preserves individuals’ health by increasing their resistance to (anti-immigrant) discrimination, or through some alternative mechanism; and (b) whether this is a universal phenomenon, applicable to immigrant groups as diverse as refugees, expatriates, and international students.
Fortunately, many online crowdsourcing platforms (e.g. Prolific, Cloud Research, Amazon Mechanical Turk) make the implementation of such study designs easy and affordable. Although concerns regarding the quality of data obtained from such platforms have been raised, for example whether the data come from inattentive, dishonest, or non-naive participants (Chandler et al., 2015; Chmielewski and Kucker, 2019), several resources exist to help guide researchers in their selection of an online crowdsourcing platform (e.g. Prolific and Cloud Research have been recommended over MTurk; Douglas et al., 2023; Peer et al., 2021). Furthermore, numerous articles offer best practices when designing and implementing online studies to ensure the efficient collection of high-quality data (Aguinis et al., 2020; Mellis and Bickel, 2020). Using these platforms and their built-in tools, researchers can selectively recruit immigrants from specific geographical regions and randomly assign them to manipulation conditions (i.e. utilize experimental designs) or repeatedly sample from the same individuals over time (i.e. utilize longitudinal designs). Investigations of how immigrants with and without experience with classic psychedelics react to hypothetical discriminatory events (e.g. vignette experiments), or how their acculturation trajectories differ based on their past or current classic psychedelic use (e.g. diary studies), would take a major step forward in determining whether classic psychedelics truly offer “enhanced resilience and well-being in the light of challenging situations” (Cavanna et al., 2021: 91).
Furthermore, despite the heavy use of North American samples in the classic psychedelic literature, the consumption of psilocybin is legal in countries as diverse as the Netherlands, Nepal, and Jamaica (Hallifax, 2022). Field studies recruiting participants from these countries would offer invaluable insight as to whether initial findings of classic psychedelics’ buffering effect on discrimination-based trauma are replicable across cultures. Similarly, if existing, transnational, large-scale drug survey datasets (e.g. Global Drug Survey; https://www.globaldrugsurvey.com/) were made openly available to researchers, this would help offset the outsized influence of the National Survey on Drug Use and Health (https://nsduhweb.rti.org/), a long-running U.S. population survey whose data are openly available and, therefore, widely used in studies on classic psychedelics (Barnett, 2022).
Finally, by studying how psychedelic experiences shape immigrants’ experiences, researchers can also help address the marked underrepresentation of minorities in psychedelic research (Michaels et al., 2018; Thrul and Garcia-Romeu, 2021), a field whose study samples are dominated by white participants. A focus on immigrant groups could help extend current findings involving classic psychedelics to minority groups, or at least unveil important limiting conditions of current findings. Such studies would be particularly timely given the growing interest in issues of diversity and inclusion in psychedelic research (Williams and Labate, 2019).
Conclusion
As both international migration and public support for xenophobic, far-right policies increases globally, the successful integration of immigrants is becoming increasingly recognized as a grand challenge for host societies. Furthermore, the acculturation process can be a long and difficult process involving threats to immigrants’ mental health, physical health, and sense of belonging, making studies on how to ease this process particularly important. The findings reported in this literature review tentatively suggest that classic psychedelics have the potential to help immigrants overcome incidents of discrimination, engage in positive social- and health-related behavior, and experience feelings of connection to others. It is therefore worth considering whether and how these substances shape the immigrant experience, an experience currently faced by the hundreds of millions of people living outside their country of birth.
Footnotes
Acknowledgments
The author thanks Sophie Moser for their insightful feedback on an early version of this article.
Declaration of conflicting interests
The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Deutsche Forschungsgemeinschaft (DFG—German Research Foundation) under Germany's Excellence Strategy—EXC-2035/1–390681379.
