The Effects of Regular Caffeine Consumption on the Brain Structure

Düzenli Kafein Tüketiminin Beyin Yapısına Etkisi

Caffeine is a psychoactive substance consumed the most on a daily basis to cope with the high need of sleep.  In a study they conducted, researchers from the University of Basel showed that regular caffeine intake could temporarily change the gray matter of the brain.

Nevertheless, an intervention in the sleep-wakefulness cycle could impair neural homeostasis, and insufficient sleep could lead to changes in the gray matter of the individual.  As shown by previous studies, lack of sleep could affect the gray matter of the brain.

Can caffeine consumption affect the brain structure due to insufficient sleep?

Attempts were made to answer this question in a study made by a research team spearheaded by Dr. Carolin Reichert and Professor Christian Cajochen of the University of Basel, along with the UPK (Psychiatric Hospital of the University of Basel).

Twenty healthy participants who regularly drank coffee on a daily basis took part in a double-blind randomized trial.  During the trial, the effects of a ten-day coffee intake were analyzed on the gray matter volumes and on the cerebral blood flow by using fMRI.  The participants were given caffeine tablets during a ten-day period, and they were asked not to consume any other substances containing caffeine.  One group was given caffeine tablets, while the other one was provided with tablets containing no active ingredients (placebo).

By the end of the ten-day duration, the researchers analyzed the gray matter volume in both groups through brain scans.  Furthermore, they researched the participants’ quality of sleep in a sleep laboratory by recording the electrical activities of the brain (EEG).

Consequently, the comparison of the data set forth that there were no differences in terms of the depth of sleep between the two groups consisting of participants that took caffeine or placebo.  Hence, the caffeine consumed as a part of the study did not cause any insufficient sleep.  Nonetheless, they spotted a significant difference in the gray matter volumes based on the intake of caffeine or placebo by the participants.

By the end of the ten-day duration, the gray matter volume of the placebo group (that did not take caffeine) was higher compared to the group that took caffeine.  The difference was particularly dramatic in the right medial temporal lobe, including the hippocampus, which is effective in the strengthening of the memory.

The frequent consumption of coffee reduced the gray matter volume in the right medial temporal lobe area, including the hippocampus.  However, although the gray matter volume seemed to be reduced by caffeine, it was renewed to a significant extent in the subjects after only a ten-day period of coffee deprivation.

– Lin, Y. S., Weibel, J., Landolt, H. P., Santini, F., Meyer, M., Brunmair, J., … & Reichert, C. (2021). Daily Caffeine Intake Induces Concentration-Dependent Medial Temporal Plasticity in Humans: A Multimodal Double-Blind Randomized Controlled Trial. Cerebral Cortex.