The research on microdosing is definitely mixed, and we need way more of it. It definitely does not seem to have dramatic effects like psychedelic treatment does. Here’s a decent overview:

Does microdosing work? In short, the jury is still out. Some studies indicate a very real and significant benefit from microdosing, whereas others are much less convincing and show little to no benefit. One recent study used a naturalistic, observational design to study 953 psilocybin microdosers compared with 180 nondosing participants for 30 days, and found “small to medium-sized improvements in mood and mental health that were generally consistent across gender, age, and presence of mental health concerns.” This study and others like it appear to confirm many anecdotal reports of people who swear by the benefits they have experienced from microdosing.

Other studies on microdosing are far less impressive. In one example the researchers conducted a randomized controlled study, which represents the strongest type of evidence because it weeds out the placebo effect. The researchers took 34 patients and randomized half of them to receive psilocybin and half to placebo. While there were some intriguing subjective effects (people felt happier and more creative), and even some changes in brain waves recorded on an EEG machine, they concluded that low-dose psilocybin mushrooms did not show objective evidence of improvements in creativity, well-being, and cognitive function. Studies such as this one support the hypothesis that the effect people receive from psychedelics at these subperceptual doses is mostly an expectancy effect, and that one needs to consume a higher dosage to receive a therapeutic benefit.

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