Researchers Say High Coffee Consumption Linked to Increased Risk for Dementia, Smaller Brains

A study published last month in the journal BMC Public Health found that consuming three to four cups of coffee a day reduces one's risk of developing, and dying from chronic liver disease. While coffee has been proven to be beneficial in moderation, new research suggests there is a fine line between enjoying and abusing the beverage.

Individuals who consume more than six cups of coffee a day face an increased risk of dementia and smaller total brain volumes, according to a new study from the University of South Australia (UniSA). 

To arrive at this conclusion, researchers led by UniSA Phd candidate Kitty Pham assessed the effects of coffee on the brains of some 17,702 individuals, aged 37 to 73 years old, and found that those who consumed more than six cups of coffee a day had a 53% increased risk of being diagnosed with dementia.   

Participant data was pulled from the UK Biobank, a large long-term biobank study. 

With the global consumption of coffee being around nine billion kilograms a year, it is imperative that people understand the "potential health implications" of coffee, Pham emphasized in a UniSA release. 

"This is the most extensive investigation into the connections between coffee, brain volume measurements, the risks of dementia, and the risks of stroke – it’s also the largest study to consider volumetric brain imaging data and a wide range of confounding factors," she added. 

Approximately 50 million people have been diagnosed with dementia around the world, according to a World Health Organisation (WHO) estimate. The syndrome is a degenerative condition that impacts one's memory, behavior, thinking and even the ability to perform everyday tasks. 

A stroke occurs when the blood supply to a part of one's brain becomes interrupted, preventing brain tissue from getting the necessary oxygen and nutrients. Globally, one in four adults aged 25 and up will have a stroke in their life, and around 13.7 million individuals will likely have their first stroke this year, according to the World Stroke Organisation.  

"Accounting for all possible permutations, we consistently found that higher coffee consumption was significantly associated with reduced brain volume – essentially, drinking more than six cups of coffee a day may be putting you at risk of brain diseases such as dementia and stroke," Pham detailed. 

This research comes shortly after another study utilized the UK Biobank and determined that those who drink any amount of coffee are at a lower risk for developing and dying from chronic liver disease. Additionally, it found that three to four cups of coffee a day should be one's limit, as there is no additional benefit from drinking more. 

Professor Elina Hyppönen, senior investigator and Director of UniSA’s Australian Centre for Precision Health, asserted that knowledge of these potential health risks should help people make more informed decisions on what coffee moderation should look like.  

"This research provides vital insights about heavy coffee consumption and brain health, but as with many things in life, moderation is the key," Hyppönen said. "Typical daily coffee consumption is somewhere between one and two standard cups of coffee. Of course, while unit measures can vary, a couple of cups of coffee a day is generally fine."