Regular Caffeine Consumption Tied to Reduced Brain Volume | Nutrition Fit



Regular caffeine consumption is tied to reduced gray matter volume but not because of its potential negative impact on sleep, new research shows.

Investigators found the impact of caffeine on gray matter appears to be temporary, with a rebound after a period of caffeine abstinence.

Yu-Shiuan Lin

It’s not possible to say whether the effect of caffeine on brain structure is harmful, first author Yu-Shiuan Lin, PhD student, Centre for Chronobiology, University of Basel, Switzerland, told Medscape Medical News.

“So far we don’t have clear evidence yet indicating any functional consequences of the reduced gray matter. We also don’t know if such restorable plasticity per se entails gains or harms,” she added.

The study was published online February 15 in the journal Cerebral Cortex.

Unclear Mechanism

To understand whether regular caffeine consumption affects brain structure because of poor sleep, the researchers studied 20 young, healthy, habitual caffeine consumers.

During the double-blind, randomized, crossover study, participants received caffeine (150 mg three times daily) or placebo capsules to take over two 10-day periods and were asked to abstain from caffeine during the study periods.

At the end of each 10-day period, the researchers examined the volume of the participants’ gray matter with MRI and sleep quality in a sleep laboratory.

Results showed no difference in participants’ depth of sleep, regardless of whether they had taken caffeine or placebo tablets. However, there was a significant difference in gray matter volume between the caffeine and placebo periods.

After 10 days of caffeine, there was a significant reduction in gray matter volume vs placebo. The difference was most evident in the right medial temporal lobe, including the hippocampus, which is essential to memory consolidation.

However, after 10 days of caffeine abstinence, gray matter volume had significantly rebounded.

The results show that “brain structure can be responsive to daily caffeine consumption,” said Lin. 

Whether the effect is linear is unclear. “We don’t know what will happen if continuing the given dose of caffeine for another longer period. Sometimes a brain adapts, sometimes it tolerates,” she added.

“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,” lead investigator Carolin Reichert, PhD, with University of Basel, said in a news release.

Preliminary but Interesting

Reached for comment, Flavio Frohlich, PhD, MSc, director of the Carolina Center for Neurostimulation at the University of North Carolina, Chapel Hill, said this is “an interesting study that addressed an intriguing hypothesis about the impact of the interaction of caffeine and sleep on brain gray matter.”

“The finding of reduced gray matter is preliminary but of interest for the planning of follow-up studies. Gray matter volume can be quite dynamic and it is plausible that directly or indirectly caffeine plays a role,” said Frohlich, who was not associated with the study.

“There was no direct evidence in terms of memory function or plasticity,” he added, “so the real-world implication of such a finding remains unclear. I do not think that such an exploratory finding should have any public health impact.”

The study was funded by the Swiss National Science Foundation. Lin and Frohlich have disclosed no relevant financial relationships.

Cereb Cortex. Published February 15, 2021. Full text

For more Medscape Neurology news, join us on Facebook and Twitter


Source link