There are plenty of research articles that come out on coffee in the medical and science journals. Equally we report quite regularly on those articles in this column and we make no apology for that because coffee is one of the most ubiquitous commodities and habits of our time. This beverage not only drives our food consumption habits, it forms a hub for our socialising, shapes our urban design and is a lynch pin of global trade. That is why studies on the effects of coffee are important and relevant, even if you aren’t a drinker yourself you know and live with someone who is. So a new study that has found that how much coffee you drink impacts your chances of developing mild cognitive impairment is fascinating.
If you ever want to blow your mind with the sheer scale of statistical data then look no further than the stats on coffee. Worlwide coffee consumption is on an upward trend and at the moment World Total Coffee Consumption stands at around 1.3 kilograms per person per year according to the World Resources Institute. That equates to more than 7.3 million metric tons consumed annually but of course the consumption varies from country to country. In Finland consumption is 12 kg per person per year, Norwegians consume 9.9 kg per year, Americans 4.2 kg, Australians 3 kg, where places like Mali, Togo, and Gabon average no consumption at all. Still, for a big percentage of the world’s population coffee drinking is very common and also very profound in its effects.
This new study involved 1,445 people aged 65-84 who were taking part in the Italian Longitudinal Study on Aging, which is a study based on samples drawn from the Italian population. The average length of follow-up for this study was 3.5 years. The researchers were looking to see if there is any link between coffee consumption and mild cognitive impairment (MCI).
Consistent concern about mental performance as you age may suggest MCI which might be present if any or all of the following are present: you forget things more often, you forget important events such as appointments or social engagements, you lose your train of thought or the thread of conversations, you feel increasingly overwhelmed by making decisions or planning steps to accomplish a task, you start to have trouble finding your way around familiar environments, or you become more impulsive and show increasingly poor judgment. MCI is considered to be a prodromal, or preceding, stage of Alzheimer’s Disease and dementia. A possible link between coffee and MCI was theorised as caffeine is a proven psychoactive stimulant.
The results showed that people who had a moderate coffee intake of 1-2 cups per day had a reduced rate of incidence of MCI compared to those who never or rarely drank coffee. However, people who increased their coffee consumption over time by more than 1 cup of coffee per day had twice the rate of MCI as did those who decreased their coffee consumption by 1 cup of coffee a day or less. People who increased their coffee consumption also had a 1.5 times higher rate of MCI compared to people who did not change their coffee habits.
So moderate and regular coffee consumption therefore offers protection against MCI compared to no coffee at all, but only if it is moderate (1-2 cups) consumption.
The effect is possibly due to the fact that long-term consumption of caffeine blocks excessive activation of adenosine A2A receptors, which possibly reduces damage caused by beta-amyloid protein that contributed to Alzheimer’s. Adenosine is a neuromodulator and blocking A2A receptors has neuroprotective effects. It is believed that a level of adenosine related activity is necessary for normal memory performance but overstimulation or under-stimulation of adenosine pathways may impair memory function. This might explain why high coffee consumption and no coffee consumption are both associated with increased MCI risk.
It seems then that you can embrace that beloved flat white (or macchiato, or latte, or long black, or whatever is your café du jour) but only twice a day.
