Study finds caffeine may shrink brain grey matter, but don't panic

The latest study on caffeine reports that it may cause notable, but temporary, changes in the brain's grey matter volume — the ramifications of which are unclear at this time. The study involved giving participants caffeine for 10 days, as well as a placebo for 10 days, and monitoring changes in their brain structure.

The new research comes from the University of Basel, revealing that regular, daily caffeine consumption may cause changes to the brain's gray matter, the part that mostly contains nerve cell bodies — not to be mistaken with the brain's white matter, which is mostly neural pathways.

This isn't the first study to link caffeine with changes in brain structure, but that past research left a mystery behind: was the brain structure altered due to sleep deprivation caused by consuming caffeine? To answer this question, the study tasked 20 young, healthy participants who had a regular coffee habit with taking caffeine tablets for 10 days.

Following the 10-day period, the participants underwent brain scans to assess their brain's grey matter volume. After that, the participants were then told to avoid caffeine and take a placebo tablet for another 10 days. Brain scans were once again performed after that time period.

After crunching the data, researchers found that the caffeine consumption didn't cause sleep disruption compared to the caffeine-free period. However, the brain scans still revealed 'a significant difference in the gray matter,' with the caffeine-free days resulting in a greater volume compared to the caffeinated days.

The biggest grey matter volume change was noted in the right media temporal lobe, according to the study, and the brain structure change appears to be temporary. The researchers note that this change doesn't necessarily mean that caffeine is something to avoid, with team leader Dr. Carolin Reichert explaining:

Our results do not necessarily mean that caffeine consumption has a negative impact on the brain. But daily caffeine consumption evidently affects our cognitive hardware, which in itself should give rise to further studies.