Drinking a cup of coffee a day could change the amount of gray matter in your brain, according to a recent report in the journal Cerebral Cortex. Fortunately, however, the writers of the analysis have observed that caffeine intake seems to have little impact on sleep efficiency, contrary to the widely held belief in the famous psychostimulant. Coffee, cola or energy drink: caffeine is the most commonly available psychoactive drug in the world.
Researchers at the University of Basel have now demonstrated in a study that daily consumption of caffeine will affect the gray matter of the brain. They observed a decrease in gray matter, much of which is found on the outer-most layer of the brain, or cortex, and is used to store information. However, the result seems to be temporary. The decline was especially striking in the right medial temporal lobe, including the hippocampus, a brain area that is central to the processing of memory.
Frequent caffeine consumption reduces gray matter volume in areas of the right medial temporal lobe, including the hippocampus. Ten days of “caffeine abstinence” helps regenerate gray matter.
Gray matter usually consists of the outer layer of the brain which consists of neural cells, better known as soma. White matter, meanwhile, consists of connecting branches that bind neurons together, along which electrical signals are transmitted.
No question-Caffeine makes most of us feel more alert. However, if we eat it in the evening, it will disturb our sleep. Sleep deficiency, in particular, will affect the gray matter of the brain, as previous studies have demonstrated. So does daily intake of caffeine have an effect on brain function due to poor sleep? The research team led by Dr. Carolin Reichert and Professor Christian Cajochen of the University of Basel and the University of Basel Psychiatric Hospital (UPK) investigated this topic in a report.
The finding was surprising: the caffeine ingested in the sample did not result in inadequate sleep. However, the researchers found differences in the gray matter, as recorded in the journal Cerebral Cortex. Gray matter refers to the areas of the central nervous system made up mostly of the nerve cell shell, while white matter forms most of the neural pathways, the long branches of the nerve cells.
A total of 20 active young adults, all of whom drink coffee on a daily basis on a regular basis, participated in the study. They were given tablets to last two 10 days and were asked not to drink any other caffeine during this period. During one study time, tablets with caffeine were taken; in the other, tablets with no active ingredient were taken (placebo). At the end of each 10-day cycle, the researchers analyzed the amount of gray matter in the subjects by means of brain scans. They also investigated the sleep efficiency of the participants in the sleep laboratory by monitoring the electrical function of the brain (EEG).
‘Our findings do not actually mean that the intake of caffeine has a negative effect on the brain,’ said Dr. Carolin Reichert at the University of Basel. ‘But the frequent intake of caffeine clearly impacts our cognitive hardware, which should, in itself, give rise to further studies.’ The researchers’ analysis sought to determine the effect of coffee consumption on sleep while drunk in the evening.
Sleep unaffected, but not gray matter
Data comparison showed that the sleep depth of the subjects was similar, regardless of whether they had taken caffeine or placebo capsules. But they saw a major change in the gray matter, based on whether the subject was given caffeine or placebo. After 10 days of placebo-i.e. “caffeine abstinence”-the amount of gray matter was higher than that of caffeine capsules after the same span of time.
The contrast was especially striking in the right medial temporal lobe, including the hippocampus, a brain area that is central to the consolidation of memory. “Our results do not necessarily mean that caffeine consumption has a negative impact on the brain,” Reichert points out. “But daily caffeine consumption evidently affects our cognitive hardware, which in itself should give rise to further studies.” She continues that in the past, the health effects of caffeine have been mainly studied in patients, but there is still a need for testing on healthy topics.
While caffeine tends to decrease the amount of gray matter, it has substantially regenerated in the test subjects after just 10 days of coffee abstinence. “The changes in brain morphology seem to be temporary, but systematic comparisons between coffee drinkers and those who usually consume little or no caffeine have so far been lacking,” Reichert notes.
