Hi, it’s Adriana here.
While I was stuck at home with a cold, bored like a latte with no espresso, came across a fascinating new study about coffee and dementia risk.
As someone who works with coffee every day, I am naturally curious whenever researchers explore how our daily coffee habits may affect our health.
This study was especially interesting because it followed more than 130,000 people for decades and looked separately at caffeinated coffee, decaffeinated coffee and tea.
So, could your daily coffee habit support long-term brain health?
The findings are encouraging, but they need to be understood carefully.
The Quick Answer: Is Coffee Associated With a Lower Dementia Risk?
A large observational study published in JAMA found that people who consumed more caffeinated coffee had a lower risk of developing dementia than those who drank little or none.
The strongest association was seen at approximately two to three cups of caffeinated coffee per day.
However, the study does not prove that coffee prevents dementia. It found a relationship between coffee-drinking habits and cognitive outcomes, but it cannot establish direct cause and effect.
What Did the Coffee and Dementia Study Examine?
The researchers analyzed data from 131,821 adults participating in two long-running American health studies:
- The Nurses’ Health Study
- The Health Professionals Follow-up Study
Participants reported their dietary habits repeatedly over the years, allowing researchers to examine long-term patterns instead of relying on a single snapshot of coffee consumption.
The participants were followed for as long as 43 years, and researchers documented 11,033 cases of dementia during that period.
The study examined whether caffeinated coffee, decaffeinated coffee and tea were associated with:
- Diagnosed dementia
- Self-reported changes in memory and thinking
- Performance on cognitive tests
- Long-term cognitive function
What Did Researchers Find About Coffee and Dementia Risk?
Participants with the highest caffeinated coffee intake had an approximately 18% lower risk of dementia compared with those who consumed little or no caffeinated coffee.
Caffeinated coffee drinkers also reported fewer problems with memory and thinking. Subjective cognitive decline was reported by 7.8% of participants in the highest-intake group, compared with 9.5% in the lowest-intake group.
Some cognitive tests also showed modestly better results among people who consumed more caffeinated coffee.
The association appeared strongest among those drinking approximately:
- Two to three cups of caffeinated coffee daily
- One to two cups of tea daily
Tea showed a similar pattern, although the association was slightly different from the one observed with coffee.
Does Coffee Prevent Dementia?
No. This study does not prove that coffee prevents dementia.
It was an observational study, which means researchers followed people’s existing habits rather than randomly assigning them to drink coffee or avoid it.
Coffee drinkers may differ from non-coffee drinkers in other ways, including their diet, physical activity, sleep habits, education or general health.
Researchers adjusted for many of these factors, but an observational study cannot eliminate every possible explanation.
The most accurate conclusion is:
Moderate caffeinated coffee consumption was associated with a lower risk of dementia and modestly better cognitive outcomes.
That is promising, but it is not the same as proving that coffee directly caused those outcomes.
Why Might Caffeinated Coffee Be Connected to Brain Health?
Researchers do not yet know exactly which components of coffee might be responsible for the association.
Coffee naturally contains caffeine and many bioactive compounds, including polyphenols. Scientists have studied these compounds for their potential roles in inflammation, cellular protection and cognitive function.
The fact that caffeinated coffee and tea showed similar patterns may suggest that caffeine contributes to the relationship.
However, coffee is complex, and caffeine may not be the only factor involved. More research is needed to identify the biological mechanisms and determine whether the connection is truly causal.
What Did the Study Find About Decaffeinated Coffee?
Decaffeinated coffee was not significantly associated with lower dementia risk or better cognitive performance in this particular study.
That does not mean decaf coffee is unhealthy or has no benefits.
It only means that researchers did not observe the same dementia-related association among decaf drinkers in this dataset.
Decaffeinated coffee can still be an excellent option for people who enjoy coffee but need or prefer to limit caffeine.
Are Two to Three Cups of Coffee Right for Everyone?
Not necessarily.
The study observed the strongest association at approximately two to three cups per day, but that should not be interpreted as a prescription.
Coffee serving sizes and caffeine levels can vary considerably depending on:
- The coffee variety
- Roast profile
- Brewing method
- Coffee-to-water ratio
- Cup size
Some people are also more sensitive to caffeine than others. Too much caffeine may contribute to restlessness, headaches, anxiety, digestive discomfort or difficulty sleeping.
Health Canada recommends that most healthy adults consume no more than 400 milligrams of caffeine per day from all sources. Lower limits apply during pregnancy, while breastfeeding and for children or adolescents.
Anyone with a health condition, medication concern or strong caffeine sensitivity should speak with a qualified healthcare professional about what is appropriate for them.
What Does This Mean for Coffee Drinkers?
The study offers encouraging news for people who already enjoy moderate amounts of caffeinated coffee.
It suggests that your daily coffee ritual may be compatible with long-term brain health and could potentially be one small part of a healthy lifestyle.
However, coffee should not be treated as a replacement for the habits that have stronger evidence behind them, including:
- Regular physical activity
- Quality sleep
- A balanced diet
- Social connection
- Managing blood pressure and other health risks
- Staying mentally engaged
Coffee may be one piece of the picture—not the entire solution.
Coffee and Dementia Risk: Frequently Asked Questions
How much coffee was linked to the lowest dementia risk?
The strongest association was observed at approximately two to three cups of caffeinated coffee per day.
Can coffee prevent dementia?
No study has proven that coffee prevents dementia. The research found an association between caffeinated coffee consumption and lower dementia risk, but it did not prove cause and effect.
Was decaffeinated coffee linked to lower dementia risk?
No significant association was found between decaffeinated coffee and lower dementia risk in this study. That does not mean decaf coffee is unhealthy.
Was tea also associated with brain health?
Yes. Drinking approximately one to two cups of tea per day was also associated with more favourable cognitive outcomes.
Should someone start drinking coffee to prevent dementia?
Not solely based on this study. People who do not currently drink coffee should not view it as a medical treatment or guaranteed prevention strategy.
Is more coffee better?
Not necessarily. The strongest association appeared at moderate intake levels, and individual caffeine tolerance varies. More is not automatically better.
A Final Thought From Your Roaster
Research like this gives us another reason to be curious about coffee, but it is not the only reason we value it.
Coffee gives us ritual, comfort, conversation and a moment to slow down—or get moving.
And while we cannot say that your morning cup will prevent dementia, it is encouraging to see researchers continue exploring how coffee may fit into a healthy and meaningful life.
So, enjoy your coffee for what it already gives you. And should it also offer a little support for long-term brain health, we will happily consider that a welcome bonus.
Make those daily cups worth brewing with coffee freshly roasted to order in Calgary.
Shop Freshly Roasted Coffee
From seed to cup, we actually grow it. We actually roast it. We actually care.
Brew boldly. Live fully.
Adriana 🤍