I ran a small single-blind ZBiotics RCT at a party I hosted recently. I prepared 30 cups, 21 of which contained a placebo and 9 of which contained a shot of ZBiotics Pre-Alcohol. People took these as they entered the party. The day after, 28[1] of them filled out a form asking how hungover they felt using a standard Acute Hangover Scale (AHS).[2]

At N=28 and only 9 people receiving the real treatment, the study is only able to detect large effects on symptom severity. I did a pretty quick analysis using Opus 4.8 in Claude Code.

I committed to publishing the results on LessWrong no matter what, and I preregistered that I would primarily analyze the effect on average AHS score as predicted by the arm people were randomly placed in, the number of drinks they had, and their weight.

The results are inconclusive. The people who took ZBiotics had slightly worse hangover symptoms on average (but slightly better ones at the median), but the N is too small to conclude much.

It seems that out of the three main variables I committed to analyze, the only one that showed a detectable relationship with hangover severity [...]

The original text contained 2 footnotes which were omitted from this narration.

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First published:
July 5th, 2026

Source:
https://www.lesswrong.com/posts/kw33A6uYPGRtvD43s/results-of-a-small-zbiotics-rct

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Narrated by TYPE III AUDIO.

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Images from the article:

Red plastic cups arranged on checkered tablecloth with form and pen.

Forest plot showing regression coefficients for AHS score with arm, drinks, and weight variables.

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“Results of a small ZBiotics RCT” by Nikola Jurkovic

LessWrong (30+ Karma)

“Results of a small ZBiotics RCT” by Nikola Jurkovic