US study links 2–3 cups of caffeinated coffee daily to lower dementia risk in observational data

A long-running observational study of adults in the United States found that regular consumption of caffeinated coffee is associated with a lower incidence of dementia and better cognitive health over time, according to sciencedaily.com sciencedaily.comsciencedaily.comsciencedaily.comOpen source ↗. The findings are based on follow-up tracking periods extending up to 43 years, comparing participants across varying beverage consumption patterns.

Researchers recorded 141 dementia cases per 100,000 people annually among adults who consumed higher amounts of caffeinated coffee. In contrast, individuals who rarely or never drank caffeinated coffee developed dementia at an annual rate of 330 cases per 100,000 people. Subjective cognitive decline was reported by 7.8% of higher-volume consumers compared to 9.5% among non-drinkers.

Optimal intake and genetic factors

The strongest statistical correlation appeared in individuals consuming two to three cups of caffeinated coffee per day. Intakes beyond this range did not provide additional measurable reductions in dementia incidence. The association remained observable regardless of participants' baseline genetic risk profiles for developing neurodegenerative conditions.

Comparison with tea and decaf

Tea consumption demonstrated similar benefits, showing the highest correlation with improved outcomes at one to two cups per day sciencedaily.comsciencedaily.comsciencedaily.comOpen source ↗. The researchers noted that tea data did not distinguish between caffeinated and decaffeinated varieties. Decaffeinated coffee did not replicate the risk reductions observed with caffeinated coffee, though the authors emphasized the study establishes correlation rather than direct causation.