What to know about a new study on coffee, tea, caffeine and dementia risk

A long-term analysis shows that people who drink caffeinated coffee and tea have a lower risk of developing dementia, although the study does not prove cause and effect. Edited by Paula Cohen In:

A long-term analysis shows that people who drink caffeinated coffee and tea have a lower risk of developing dementia, although the study does not prove cause and effect.

Dr. Céline Gounder, CBS News medical contributor and editor-at-large for public health at KFF Health News, warned that the results should be taken "with a massive grain of salt." 

The research, published in the medical journal JAMA on Monday, analyzed data on 131,821 people who had participated in two studies that ran from 1986 to 2023. Of that group, 11,033 developed dementia during the period studied.

The researchers compared each participant's self-reported intake of coffee, caffeinated tea and decaffeinated coffee, and tracked records of their cognitive health over time. They found that men and women who drank the most caffeinated coffee had an 18% lower risk of dementia when compared to those who reported little or no caffeinated coffee consumption. Caffeinated coffee drinkers also showed a lower prevalence of cognitive decline, the researchers said. 

The benefits appeared to be most pronounced in people who drank two to three cups of caffeinated coffee a day, the researchers said, or one to two cups of caffeinated tea.