Human Microdosing Research: What Controlled Studies Show

How to read this page

Studies of microdosing come in very different designs, and the design changes what the result can tell you. This page separates controlled studies, where some people get an inactive placebo and nobody knows who got what, from surveys and open studies, where people choose to take part and everyone knows what they are taking. Evidence labels used here: mixed, insufficient evidence and no good evidence of benefit. No amounts or schedules are given on this page.

Controlled studies

• Single low LSD doses in a lab. Twenty healthy young adults received placebo or one of three very low LSD amounts in random order. The drug produced dose-related subjective effects, but other mood measures, cognition and physiological measures were unaffected. [1]
• Repeated low LSD doses in a lab. In a double-blind study of repeated doses in healthy adults, LSD did not improve mood or affect performance on psychomotor or most emotional tasks. The authors concluded that changes in mood or cognition were negligible. [2]
• Psilocybin mushrooms, double-blind. A study of 34 people who were starting to microdose with psilocybin mushrooms found no evidence of enhanced well-being, creativity or cognitive function. The effects people felt were stronger only for those who correctly guessed which condition they were in. [3]
• Preregistered psilocybin study. Psilocybin microdosing did not affect emotion processing or symptoms of anxiety and depression compared with placebo. [4]
• Psilocybin truffles, two trials. In two randomized, double-blind, placebo-controlled trials in semi-naturalistic settings, microdosing did not significantly affect behavioral or subjective measures compared with placebo, and participants stayed effectively blinded. [5]
• Creativity, three trials pooled. In 171 people pooled across three double-blind trials, the only difference was on one measure of original thinking, and only when relative dose was taken into account. Other divergent and convergent thinking scores showed no effect. [6]

A "self-blinding" study

Researchers asked people who were already microdosing to add a placebo to their own routine using online instructions, without clinical supervision. The study was completed by 191 participants. [7] The microdose group improved over four weeks, but the placebo group also improved, and no significant differences between groups were observed. [7] The small differences that did appear can be explained by participants breaking blind, meaning they guessed which capsule they had taken. [7] See Placebo and Expectancy in Microdosing.

Surveys and open studies

• Large online comparison. A mobile-app survey compared self-selected microdosers (4,050 people) with non-microdosers (4,653 people). Microdosers were more likely to report a history of mental health concerns. [8]
• Planned microdosers followed over time. A prospective study in which 81 people completed the main four-week endpoint saw improved well-being, but positive expectations at the start predicted the improvement, suggesting a placebo response. [9]
• Open-label LSD study in depression. Nineteen adults with depression, most already taking an antidepressant, took part in an open-label trial (no placebo). The authors noted the study was limited by its open-label design and small sample size. [10]

What the reviews conclude

• A 2026 meta-analysis covering 24 studies and 3,681 participants found no consistent immediate benefits for depressive, anxiety or stress symptoms in healthy adults. Randomized trials were inconclusive, and observational studies showed improvements that were likely influenced by expectancy or lifestyle factors. [11]
• A critical review of 57 human studies found that observational studies generally report more benefits, while experimental trials tend to yield more null findings. It called the evidence inconclusive and said it warrants caution. [12]
• A 2026 review of psilocybin mushroom and truffle microdosing rated the certainty of evidence as low and said a causal effect cannot be inferred. [13]

Where the evidence stands

• Mood and well-being in healthy adults: mixed, leaning toward no good evidence of benefit in blinded trials.
• Thinking and creativity: mixed; one pooled analysis found a narrow signal, others found none. See Microdosing Claims: Productivity, Creativity, Mood and Cognition.
• People with depression or other conditions: insufficient evidence. Only small open-label work and registered protocols exist.
• Long-term safety: insufficient evidence. See Long-Term Safety Uncertainty in Microdosing.

Surveys cannot show cause and effect, and controlled trials so far have been small and short. For help reading any single study, see How to Read a Psychedelic Clinical Trial.