A systematic study of microdosing psychedelics
This observational study (n=98) investigates the effects of microdosing psychedelics on psychological functioning over six weeks. It finds increased functioning on dosing days, reduced depression and stress, lower distractibility, increased absorption, and increased neuroticism. A second study (n=263) reveals a discrepancy between expected and reported benefits, highlighting the need for controlled research.
Abstract
The phenomenon of ‘microdosing’, that is, regular ingestion of very small quantities of psychedelic substances, has seen a rapid explosion of popularity in recent years. Individuals who microdose report minimal acute effects from these substances yet claim a range of long-term general health and wellbeing benefits. There have been no published empirical studies of microdosing and the current legal and bureaucratic climate makes direct empirical investigation of the effects of psychedelics difficult. In Study One we conducted a systematic, observational investigation of individuals who microdose. We tracked the experiences of 98 microdosing participants, who provided daily ratings of psychological functioning over a six week period. 63 of these additionally completed a battery of psychometric measures tapping mood, attention, wellbeing, mystical experiences, personality, creativity, and sense of agency, at baseline and at completion of the study. Analyses of daily ratings revealed a general increase in reported psychological functioning across all measures on dosing days but limited evidence of residual effects on following days. Analyses of pre and post study measures revealed reductions in reported levels of depression and stress; lower levels of distractibility; increased absorption; and increased neuroticism. To better understand these findings, in Study Two we investigated pre-existing beliefs and expectations about the effects of microdosing in a sample of 263 naïve and experienced microdosers, so as to gauge expectancy bias. All participants believed that microdosing would have large and wide-ranging benefits in contrast to the limited outcomes reported by actual microdosers. Notably, the effects believed most likely to change were unrelated to the observed pattern of reported outcomes. The current results suggest that dose controlled empirical research on the impacts of microdosing on mental health and attentional capabilities are needed.
Research Summary of 'A systematic study of microdosing psychedelics'
Introduction
Microdosing denotes the regular ingestion of very small, sub‑perceptual amounts of serotonergic psychedelics (commonly LSD or psilocybin) purported to confer benefits such as improved mood, creativity, focus and wellbeing. The phenomenon has attracted substantial popular and media interest and large online communities, but peer‑reviewed empirical work is scarce. The broader psychedelic literature indicates that higher doses of classic psychedelics produce lasting changes in mood, cognition and perception through serotonergic (5‑HT2A) mechanisms and altered network connectivity, providing a plausible biological rationale for microdosing, yet the evidence specific to low, repeated doses is limited and potentially confounded by expectancy effects. Polito and colleagues designed an initial exploratory programme to characterise self‑reported short‑ and longer‑term effects of microdosing and to gauge the role of expectancies. Study One was a six‑week, observational tracking study of people who microdose, combining daily brief ratings with comprehensive psychometric batteries at baseline and after six weeks. Study Two surveyed expectations about the effects of a hypothetical six‑week microdosing regimen in a larger sample from the same online communities, to assess whether popular expectations align with the effects observed in Study One. Nine psychological domains were selected a priori for investigation: mood, attention, wellbeing, mindfulness, mystical experience, personality, absorption, creativity and sense of agency.
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Study Details
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Polito, V., & Stevenson, R. J. (2019). A systematic study of microdosing psychedelics. PLOS ONE, 14(2), e0211023. https://doi.org/10.1371/journal.pone.0211023
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