Coffee, tea, and caffeine consumption and prevention of late-life cognitive decline and dementia: A systematic review

Abstract

A prolonged preclinical phase of more than two decades before the onset of dementia suggested that initial brain changes of Alzheimer's disease (AD) and the symptoms of advanced AD may represent a unique continuum. Given the very limited therapeutic value of drugs currently used in the treatment of AD and dementia, preventing or postponing the onset of AD and delaying or slowing its progression are becoming mandatory. Among possible reversible risk factors of dementia and AD, vascular, metabolic, and lifestyle-related factors were associated with the development of dementia and late-life cognitive disorders, opening new avenues for the prevention of these diseases. Among diet-associated factors, coffee is regularly consumed by millions of people around the world and owing to its caffeine content, it is the best known psychoactive stimulant resulting in heightened alertness and arousal and improvement of cognitive performance. Besides its short-term effect, some case-control and cross-sectional and longitudinal population-based studies evaluated the long-term effects on brain function and provided some evidence that coffee, tea, and caffeine consumption or higher plasma caffeine levels may be protective against cognitive impairment/decline and dementia. In particular, several cross-sectional and longitudinal population-based studies suggested a protective effect of coffee, tea, and caffeine use against late-life cognitive impairment/decline, although the association was not found in all cognitive domains investigated and there was a lack of a distinct dose-response association, with a stronger effect among women than men. The findings on the association of coffee, tea, and caffeine consumption or plasma caffeine levels with incident mild cognitive impairment and its progression to dementia were too limited to draw any conclusion. Furthermore, for dementia and AD prevention, some studies with baseline examination in midlife pointed to a lack of association, although other case-control and longitudinal population-based studies with briefer follow-up periods supported favourable effects of coffee, tea, and caffeine consumption against AD. Larger studies with longer follow-up periods should be encouraged, addressing other potential bias and confounding sources, so hopefully opening new ways for diet-related prevention of dementia and AD.

Chocolate Consumption is Associated with a Lower Risk of Cognitive Decline

“…Another issue is the insufficient detail of the food questionnaire regarding the characterization of the chocolate type, namely discriminating whether it was milk of dark chocolate, as well as limited published data regarding different types of chocolate/cocoa foods and beverages, which limits a more precise quantification of its components. Finally, chocolate consumption may be related with healthy and social lifestyles that contribute to the protective effects, or some medical conditions may be overrepresented and negatively affect cognitive functions [45], and therefore residual confounding may have affected our estimates, despite several potentially important confounding factors were taken into account.…”

No Effects of Black Tea on Cognitive Decline Among Older US Men: A Prospective Cohort Study

“…Many factors may affect the findings from a particular study population, and both frequency of consumption and consistency of consumption are critical. Indeed, previous studies concluded that consistent and moderate coffee consumption was associated with a reduced risk of cognitive decline and cognitive impairment [16]. An earlier study showed that adjustment for potential confounders can markedly change the main results on the relationship between coffee consumption and mortality [17].…”

Prolonged consumption of energy drinks does not affect the processes of memory, and increases the activity of transaminases, and cholesterol concentration – animal model study results

“…also, Panza et al demonstrated that consumption of caffeine-rich beverages prevents dementia in humans. the authors emphasize that this effect is more visible in women than in men [14]. on the other hand, Xu et al proved that caffeine assists in the repair of gray matter damage in the mouse nervous system by decreasing a1 adenosine receptor expression [15].…”