Drinking so much coffee every day can lead to brain shrinkage and increase the risk of dementia

senior woman making coffee at home in the kitchen.

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More than 7 in 10 Americans drink coffee daily, averaging about three cups a day, according to the according National Coffee Association. At that pace (and at the right time of day, AKA not too close to bedtime), coffee acts like a pick-me-up that can give a surprisingly wide range of health benefits.

But new research published in June 2021 in the journal Nutritional Neuroscience proves that – as with most things in life – there can be too much of a good thing. After diving into 8 to 12 years of data collected on the coffee habits of more than 398,000 adults who took part in a UK study, the Australian research team found that drinking more than six cups of coffee a day was associated with a 53% increased risk of dementia and smaller brain volume.

So while coffee may be good to give you a little energy, it may not be so good for you brain health-if you consume it in large quantities. Those who reported drinking more than six cups a day had a “significant increase” in dementia risk, the researchers say, or about 53% higher than their peers who drank one to two cups a day. (Tea drinkers seemed to experience no ill effects, the researchers say.)

These findings held true even after the scientists took into account variations in lifestyle and other factors, and were found in both men and women at a wide variety of ages. The more Java people drank more than six cups a day, the more brain shrinkage they experienced, as determined by MRI scans.

The study authors admit that this does not necessarily mean that the coffee leads to brain shrinkage or dementia, but the factors are correlated. They also monitored stroke risk as it was linked to high coffee consumption, and found no evidence of an association.

Related: The healthiest way to make a cup of coffee koffie

While all people experience some reduction in brain volume over time, a faster and greater amount of brain volume loss can lead to: previous dementia.

Because the caffeine in coffee allows it to cross the blood-brain barrier, one cup can make you more alert, help with concentration, boost mood and reduce feelings of depression, according to another study in the journal. Practical Neurology. And in moderation, coffee is linked to a live longer, less risk for heart disease and a healthier liver.

But all those benefits seem to max out at about two to four cups a day when you’re talking about your brain. (Yes, even taking into account that coffee is the main source of antioxidants for Americans.)

Elina Hypponen, study co-author and director of the Australian Center for Precision Health at the University of South Australia Cancer Research Institute, said: TODAY that their study results did not provide enough information to quantify exactly how much is too much. The findings suggest it’s probably best to keep caffeine intake to 300 milligrams or less per day (about four 8-ounce cups). Keep in mind that most mugs found in American kitchens typically contain between 12-16 ounces.

Drinking water next to every cup of coffee also won’t hurt, Hypponen adds, to potentially prevent the caffeine-related dehydration that can have a detrimental effect on the brain. And with that H2O and coffee, could we recommend refueling with this? best foods for brain health?