For some people, coffee is like air – necessary for survival. As the saying goes, however, there can be too much of a good thing. Yes, we need air, but too much kills cells, so medical professionals resuscitating patients with pure oxygen may cause more brain damage than would be the case otherwise. Is there an analog to drinking too much coffee?
A study published in Nutritional Neuroscience shows an association between consuming more than 6 cups of coffee daily and decreased brain volume. Significantly, however, it is not clear if there is a causal connection between consuming large quantities of coffee daily and brain shrinkage over time. The study did not measure, for example, the brain volume of individuals prior to developing the habit of consuming 6 cups of coffee daily, and the brain volume of those same individuals years later. Instead, researchers compared the amount of coffee consumed every day to brain images. So, what they observed was a time slice that showed correlations between coffee consumption and brain size.
Moreover, the implications of brain size for health were not part of the study, although, since there is a correlation between brain ‘shrinkage’ and dementia, the researchers, led by Kitty Pham concluded, “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.” The results also suggest that those who drink 1 to 2 cups a day do not thereby increase their risk for dementia. So, enjoy your coffee, but do so in moderation.