The Study
High coffee consumption, brain volume and risk of dementia and stroke
This study found that people who drink a lot of coffee tend to have smaller brains and a higher chance of getting dementia, but it doesn't prove that coffee makes those things happen. It's like noticing that people who wear hats often also have colds — that doesn't mean hats cause colds.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
This study looked at how drinking coffee every day affects the brain and chances of getting dementia as people get older.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 548 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1While the brain volume changes are small, the dementia risk jump at very high intake is large enough to be concerning — especially since light coffee drinkers had the lowest risk.
- 2People who drank more than 6 cups of coffee a day had a 53% higher chance of dementia than those who drank 1–2 cups.
- 3Every extra cup was linked to a tiny but measurable drop in brain volume — about 1.42 mL less total brain size per cup.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Nutritional Neuroscience
Year
2021
Authors
Kitty Pham, A. Mulugeta, Ang Zhou, J. O'Brien, D. Llewellyn, E. Hyppönen
Related Content
Claims (6)
Middle-aged and older adults who drink 2 to 3 cups of caffeinated coffee per day have an 18–19% lower risk of developing dementia compared to those who drink less, do not drink coffee, or drink decaffeinated coffee. This association does not occur in women.
People who drink decaffeinated coffee have a higher rate of dementia than people who drink 1–2 cups of caffeinated coffee per day.
Regular coffee drinking shows no measurable link to white matter hyperintensity volume, a brain imaging marker of small blood vessel damage.
People who never drink coffee and those who drink more than six cups a day are more likely to develop dementia than people who drink one to two cups a day.
Adults who drink more than six cups of coffee daily have a 53% higher odds of developing dementia than those who drink one to two cups daily, after accounting for age, sex, socioeconomic status, and other lifestyle factors.
People who drink one more cup of coffee per day have slightly smaller total brain volume, grey matter, white matter, and hippocampal volume compared to those who drink less, after accounting for age, sex, and lifestyle differences.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.