Coffee consumption linked to dementia risk, new study suggests

Moderate Coffee Consumption Linked to Lower Dementia Risk, Long-Term Study Finds

Drinking two to three cups of coffee daily may reduce the risk of dementia by up to 18%, according to new research published in The Journal of the American Medical Association.

American researchers analyzed data spanning four decades from more than 130,000 healthcare professionals, discovering that moderate consumption of caffeinated beverages appears to protect against cognitive decline. The extensive study suggests there may be an optimal “sweet spot” for caffeine intake that maximizes these protective benefits.

The findings address inconsistencies in previous research that had been limited by insufficient follow-up periods. To overcome this limitation, scientists drew from the Nurses’ Health Study and the Health Professionals Follow-Up Study, tracking participants from middle age through their senior years for up to 43 years.

“When searching for possible dementia prevention tools, we thought something as prevalent as coffee may be a promising dietary intervention,” said senior study author Daniel Wang, an assistant professor at Harvard Medical School.

Throughout the study period, participants completed dietary questionnaires every four years, allowing researchers to account for changing consumption patterns over time. The team monitored for both clinical dementia diagnoses and subtle shifts in cognitive function, controlling for variables such as smoking, physical activity, and underlying health conditions.

Of the 131,821 participants, 11,033 developed dementia during the follow-up period. Those with the highest caffeinated coffee intake demonstrated an 18% lower risk of dementia compared to those reporting little or no consumption. These individuals also performed better on tests measuring overall cognitive function.

The research revealed that participants consuming two to three cups of caffeinated coffee or one to two cups of tea daily experienced the most pronounced cognitive benefits. Interestingly, decaffeinated coffee did not produce similar protective effects, suggesting that caffeine likely plays a key role in protecting brain health.

Both coffee and tea contain bioactive compounds beyond caffeine, including polyphenols that may reduce inflammation and cellular damage. Researchers referred to these properties as “neuroprotective” and noted they might help defend against cognitive deterioration.

The study’s results carry significant public health implications. Dementia currently affects more than six million Americans and 55 million people worldwide, with the National Institutes of Health reporting over 100,000 U.S. deaths annually from the condition. Experts emphasize that early prevention is crucial, as current treatments offer only modest benefits once symptoms appear.

Contrary to concerns raised in some previous research, this study found no negative effects from higher caffeine consumption. The neuroprotective benefits remained consistent even among individuals with a high genetic predisposition to dementia.

Despite the encouraging findings, Wang cautioned that the protective effect is relatively small and should be viewed as just one component of a comprehensive approach to maintaining cognitive health during aging.

The research adds to growing evidence that lifestyle factors, including dietary choices, may play important roles in preventing or delaying neurodegenerative conditions. As the global population ages and dementia rates continue to rise, identifying accessible preventive measures like coffee consumption could have significant implications for public health strategies.

For the millions of coffee drinkers worldwide, the findings provide reassurance that their daily habit may offer benefits beyond the immediate alertness caffeine provides. However, experts stress that maintaining brain health requires a multifaceted approach that includes physical activity, social engagement, cognitive stimulation, and management of cardiovascular risk factors, alongside potential dietary interventions like moderate coffee consumption.