Moderate cannabis use linked to larger brain regions and better cognition in middle-aged and older adults
A UK Biobank analysis of 26,362 adults aged 40–77 finds that greater lifetime cannabis use is generally associated with larger regional brain volumes and better cognitive performance, especially with moderate use; some measures peak at high use, but one region (posterior cingulate) shows lower volume with more use, and sex differences appear but are not consistent. The study emphasizes nuance, cautions against causal conclusions, and notes context (patterns, products, timing) matters, with future work on brain connectivity and other substances like psilocybin.
