Caffeine appears to reduce the volume of gray matter, effect being reversible (opens in new tab)

It must be hard to do double-blind studies about caffeine, since at a typical dose it’d easy to tell the difference between caffeine and a placebo.

Interesting. There are already a few studies about caffeine and the brain-- while drinking caffeine can decrease the chances of dementia, this effect reverses if you drink too much(over 6 cups day)

>In the CAIDE study, coffee drinking of 3-5 cups per day at midlife was associated with a decreased risk of dementia/AD by about 65% at late-life. In conclusion, coffee drinking may be associated with a decreased risk of dementia/AD. https://pubmed.ncbi.nlm.nih.gov/20182054/

>Conducted at UniSA's Australian Centre for Precision Health at SAHMRI and a team of international researchers*, the study assessed the effects of coffee on the brain among 17,702 UK Biobank participants (aged 37-73), finding that those who drank more than six cups of coffee a day had a 53 per cent increased risk of dementia https://www.eurekalert.org/news-releases/527517

Intuitively, this seems like a reason to quit coffee. But study after study seems to suggest moderate coffee consumption (under 6 cups daily) is associated with less Alzheimer’s, less Parkinson’s, dementia of any sort, better memory… not to mention other nice things like lower incidence of diabetes and longer lifespan. Super interesting all around.