“A new randomized controlled study of LSD microdosing has failed to find evidence that the psychedelic practice results in improvements to mood or cognition.”
The glowing microdosing studies skipped the placebo. This one used 56 adults, double-blind, and mood and cognition matched the sugar pill. The higher dose made some people feel a little high, which is not the same as getting smarter. The productivity boost was mostly expectation, and expectation is free.