Myth-buster
NAC failed to improve attention or any other cognitive measure in a 12-week trial of 481 children — despite promising mouse data.
This is the first large, rigorous test of NAC for attention in a clinical population, and the null result directly contradicts the hype from earlier animal studies — but because the trial was done in children with a specific genetic condition (neurofibromatosis type 1), the finding may not apply to healthy adults or other groups.
In a double-blind, placebo-controlled trial, children and youth with neurofibromatosis type 1 took about 70 mg/kg of N-acetyl cysteine daily for 12 weeks. The supplement did not improve attention, motor function, or any other cognitive or behavioral outcome compared to placebo. The study was well-designed but tested a specific clinical population, so the results don't rule out possible effects in other groups — but they do challenge the idea that NAC is a straightforward cognitive enhancer.
Where this fits in the evidence
This is among the first studies we've indexed on N-Acetyl Cysteine for Improved Attention Span — treat it as an early signal until more research accumulates.
The study
- Randomized Controlled Trial (RCT)
- n = 481
- 2026-07
- Pediatric neurology
This is a plain-language summary of a research finding, not medical advice. Pillser surfaces research signals to help you decide what's worth investigating — always consult a qualified professional before changing what you take.