Caffeine is the world’s most widely used psychostimulant, and for many of us, coffee is our preferred delivery system. An enhancer of psychomotor performance, alertness, and reaction time, coffee has become a necessary student addiction, with 94 per cent of UK students regularly buying coffee on campus in 2025.
However, caffeine carries a cautionary reputation, with guidelines often citing dangers to cardiac health, mineral absorption, and neurological disturbances such as panic attacks and seizures.
Yet, increasingly, researchers propose that these warnings crucially overlook caffeine’s benefits, particularly in relation to the brain.
Harvard epidemiologist Yu Zang has conducted a 130,000-participant study which suggests caffeine may serve as a protector against cognitive decline. The study referenced two decade-long health studies recording participants caffeine consumption and diets, alongside systematic monitoring of cognitive function through questionnaires.
The results displayed a clear link between moderate caffeine intake – around two to three cups of coffee per day – and a decreased dementia risk. Higher consumption of caffeine also showed benefits. Even more encouraging is that the association held strong for those carrying APOE4 allele, the genetic variant that raises risk of Alzheimer’s by two to three times.
Another study highlights the benefits of coffee for cerebral health. It found that those who drank three to five cups per day had a roughly 63 per cent lower risk of Alzheimer’s disease, and 67 per cent of dementia later in life, in comparison with lower consumers.
Notably, decaffeinated coffee has not produced the same results, suggesting that it is the caffeine, as opposed to the beneficiary polyphenols or alkaloids, which also compose coffee, that are integral to cognitive preservation.
Caffeine’s protective effect could be explained by its functioning as a ‘competitive antagonist’, reducing the action of the chemical adenosine, which typically slows organ activity, and leads us to feel tired. Caffeine is thus able to block adenosine receptors and increase neurotransmitters such as dopamine and adrenaline, which support cognitive function by increasing blood flow the brain. This is instrumental to cognitive stimulation and thus preventative of its decline.
Whilst observational studies cannot prove causation, and results have varied when intersecting with factors such as diet and gender, this growing research area is certainly signalling that a daily cup of coffee should not be considered a health hazard.
So, don’t worry, enjoy your pre-lectures cup of coffee in peace!
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