Something’s Brewing with Coffee and Your Brain
Deja brew- stick with one cup or two. America’s favorite breakfast beverage is best in moderation, according to a new study presented at the 2024 Alzheimer’s Association International Conference (AAIC).
Consuming over three cups of coffee daily has been linked with more rapid cognitive decline over time suggests a recent large study. Researchers evaluated the effect of different amounts of tea and coffee on fluid intelligence- a combo platter of cognitive functions such as abstract reasoning, pattern recognition, and logical thinking.
Study investigator Kelsey R. Sewell, PhD, of the Advent Health Research Institute, Orlando, Florida states, “It’s the old adage that too much of anything isn’t good. It’s all about balance, so moderate coffee consumption is okay but too much is probably not recommended,”.
One of the World’s Most Popular Drinks
Worldwide, coffee is one of the most popular drinks to consume. Coffee beans offer a variety of bioactive compounds, including caffeine, chlorogenic acid, and limited amounts of vitamins and minerals.
Observational and epidemiologic studies suggest that consumption of both coffee and tea has protective effects against stroke, heart failure, cancers, diabetes, and Parkinson’s disease.
Other studies also suggest that coffee may reduce the risk of Alzheimer’s disease, said Dr. Sewell. But, limited longitudinal studies on the link between coffee and tea intake and cognitive decline are available, especially in distinct cognitive domains.
A previously published study by Dr. Sewell’s group in older adults without cognitive impairment discovered greater coffee consumption was associated with slower cognitive decline and slower accumulation of brain beta-amyloid.
Their new study adds data to the prior research and investigates the association between coffee and tea intake and cognitive decline over time in a larger sample of older adults.
This new research included 8451 primarily female (60%) and White (97%) adults without cognitive impairment, older than 60 (mean age, 67.8 years) in the UK Biobank, a large-scale research resource with in-depth, deidentified genetic and health information from half a million UK participants. Study participants had a mean body mass index (BMI) of 26, and roughly 26% were carriers for the gene apolipoprotein epsilon 4 (APOE e4).
Coffee and tea intake was divided into tertiles: high, moderate, and no consumption.
For daily coffee intake, 18% reported high intake (drinking four or more cups), 58% reported moderate consumption (drinking one to three cups), and 25% reported that they never drink coffee. In daily tea consumption, 47% reported high consumption (drinking four or more cups), 38% reported moderate consumption (drinking one to three cups), and 15% reported that they never drink tea.
The study evaluated cognitive function at the start and at least two extra patient visits. Linear mixed models were used by researchers to evaluate the link between coffee and tea intake and cognitive outcomes. Models were adjusted for age, sex, Townsend deprivation index (reflecting socioeconomic status), ethnicity, APOE e4 status, and BMI.
Steeper Decline
Slower cognitive decline in fluid intelligence after nearly 9 years of follow-up was observed in subjects who never drank coffee or consumed it moderately, compared with those who drank 4 or more cups daily.
Per Dr. Sewell, “We can see that those with high coffee consumption showed the steepest decline in fluid intelligence across the follow up, compared to those with moderate coffee consumption and those never consuming coffee”. She also notes that moderate coffee intake may be protective against cognitive decline.
Tea drinker results were different. For those who never drank tea, a greater decline was seen in fluid intelligence compared to moderate or high-consumption drinkers
Because this is an observational study, “we still need randomized controlled trials to better understand the neuroprotective mechanism of coffee and tea compounds,” said Dr. Sewell.
Dr. Sewell noted at the conference that moderate coffee drinking could be protective through the “molecular level (possibly involving amyloid toxicity) and the behavioral level (possibly involving sleep patterns).
“We hope that coffee and tea intake could contribute to the development of a safe and inexpensive strategy for delaying the onset and reducing the incidence for Alzheimer’s disease.”
Recall bias is a limitation in the study given self-reports of coffee and tea intake, though Sewell notes this may not be such an issue as coffee and tea tend to be habitual habits.
No data on midlife coffee or tea intake was available and the impact of various preparation methods for coffee and tea were not included (i.e. black versus green tea). In addition, the study did not control for smoking, according to Dr. Sewell.
When asked if the study controlled for smoking, Dr. Sewell said it didn’t but added that it would be interesting to explore its impact on cognition. 1
How Can You Prevent Cognitive Decline?
· Limit coffee or tea intake to 3 cups or less per day.
· Avoid heavy cream or sugary syrups in your coffee or tea. These add unwanted fat and added sugar to your drinks.
· Don’t smoke! Smoking is a risk factor for several conditions, including dementia. 2
· Add a Tbsp. of cocoa powder to your coffee for additional antioxidants. Compounds in cocoa have been found to reduce the risk of cognitive decline. 3
· Control blood pressure and prevent dementia through the MIND diet. Include foods high in antioxidants such as blueberries, green leafy vegetables, and whole grains regularly. 4
· Stay active. Regular physical activity improves blood flow to the brain, which is key to preventing dementia. 5
· Include fatty fish such as mackerel, salmon, and tuna in your diet at least twice a week. These contain anti-inflammatory omega-3 fatty acids, which protect your brain. 6
· Be social. Staying social helps keep your brain sharp and has been found to reduce both depression and dementia as we age. 7
· Challenge your brain with puzzles or word games. Scrabble anyone?
· Keep reading, journal, or write letters. All of these lifetime activities are associated with decreased cognitive decline. 8
Lisa Andrews, MEd, RD, LD
References:
1. https://www.medscape.com/viewcollection/37511
2. Nordestgaard LT, Christoffersen M, Frikke-Schmidt R. Shared Risk Factors between Dementia and Atherosclerotic Cardiovascular Disease. Int J Mol Sci. 2022 Aug 29;23(17):9777. doi: 10.3390/ijms23179777. PMID: 36077172; PMCID: PMC9456552.
3. Zeli C, Lombardo M, Storz MA, Ottaviani M, Rizzo G. Chocolate and Cocoa-Derived Biomolecules for Brain Cognition during Ageing. Antioxidants (Basel). 2022 Jul 12;11(7):1353. doi: 10.3390/antiox11071353. PMID: 35883844; PMCID: PMC9311747.
4. Stefaniak O, Dobrzyńska M, Drzymała-Czyż S, Przysławski J. Diet in the Prevention of Alzheimer's Disease: Current Knowledge and Future Research Requirements. Nutrients. 2022 Oct 30;14(21):4564. doi: 10.3390/nu14214564. PMID: 36364826; PMCID: PMC9656789.
5. De la Rosa A, Olaso-Gonzalez G, Arc-Chagnaud C, Millan F, Salvador-Pascual A, García-Lucerga C, Blasco-Lafarga C, Garcia-Dominguez E, Carretero A, Correas AG, Viña J, Gomez-Cabrera MC. Physical exercise in the prevention and treatment of Alzheimer's disease. J Sport Health Sci. 2020 Sep;9(5):394-404. doi: 10.1016/j.jshs.2020.01.004. Epub 2020 Feb 4. PMID: 32780691; PMCID: PMC7498620.
6. Welty FK. Omega-3 fatty acids and cognitive function. Curr Opin Lipidol. 2023 Feb 1;34(1):12-21. doi: 10.1097/MOL.0000000000000862. Epub 2022 Nov 25. PMID: 36637075.
7. Shen C, Rolls ET, Cheng W, Kang J, Dong G, Xie C, Zhao XM, Sahakian BJ, Feng J. Associations of Social Isolation and Loneliness With Later Dementia. Neurology. 2022 Jul 11;99(2):e164-e175. doi: 10.1212/WNL.0000000000200583. PMID: 35676089.
8. Wu Z, Pandigama DH, Wrigglesworth J, Owen A, Woods RL, Chong TT, Orchard SG, Shah RC, Sheets KM, McNeil JJ, Murray AM, Ryan J. Lifestyle Enrichment in Later Life and Its Association With Dementia Risk. JAMA Netw Open. 2023 Jul 3;6(7):e2323690. doi: 10.1001/jamanetworkopen.2023.23690. PMID: 37450299; PMCID: PMC10349343.
