Moderate consumption of caffeinated coffee or tea is linked to an 18% lower risk of dementia and better cognitive performance. The corresponding study was published in JAMA.
"We also compared people with different genetic predispositions to developing dementia and saw the same results- meaning coffee or caffeine is likely equally beneficial for people with high and low genetic risk of developing dementia," said lead author of the study, Yu Zhang, MBBS, a PhD student at Harvard Chan School of Public Health, in a press release.
For the study, the researchers analyzed data from close to 132,000 participants with an average age of 46 years old at the start of the study. Intakes of caffeinated coffee, decaffeinated coffee, and tea were collected every 2-4 years via a food frequency questionnaire.
The primary outcome was dementia, identified via death records and physician diagnoses, while secondary outcomes included subjective cognitive decline and cognitive function assessed via telephone-based neuropsychological tests. The participants were followed for up to 43 years, during which time 11,033 developed dementia.
Ultimately, those drinking higher amounts of caffeinated coffee were 18% less likely to develop dementia than those who rarely or never drank it. They were also less likely to develop cognitive decline and performed better on cognitive tests.
High intake of tea yielded similar results; however, decaffeinated coffee was not linked to lower dementia risk or better cognitive performance. The strongest effects were seen among those drinking 2-3 cups of caffeinated coffee or 1-2 cups of tea each day.
"We also compared people with different genetic predispositions to developing dementia and saw the same results- meaning coffee or caffeine is likely equally beneficial for people with high and low genetic risk of developing dementia," said lead author of the study, Yu Zhang, MBBS, a PhD student at Harvard Chan School of Public Health, in a press release.
"While our results are encouraging, it's important to remember that the effect size is small and there are lots of important ways to protect cognitive function as we age. Our study suggests that caffeinated coffee or tea consumption can be one piece of that puzzle,” said senior author of the study, Daniel Wang MD, assistant professor at Harvard Medical School, in a press release.
Sources: Science Daily, JAMA
