Health & Wellbeing

Caffeine consumption found to alter brain structure

Caffeine consumption found to ...
Research has found caffeine reduces the volume of gray matter in a brain but this effect is temporary and its influence on cognitive processes is unclear
Research has found caffeine reduces the volume of gray matter in a brain but this effect is temporary and its influence on cognitive processes is unclear
View 1 Image
Research has found caffeine reduces the volume of gray matter in a brain but this effect is temporary and its influence on cognitive processes is unclear
1/1
Research has found caffeine reduces the volume of gray matter in a brain but this effect is temporary and its influence on cognitive processes is unclear

A unique placebo-controlled study has found daily caffeine consumption can significantly reduce the volume of gray matter in the human brain. The researchers stress these findings do not imply caffeine negatively impacts the brain but instead suggest the drug may induce a kind of temporary neural plasticity that is worthy of further investigation.

Our brain and central nervous system is generally composed of both gray and white matter. Gray matter consists of neural cell bodies and nerve synapses, while white matter is primarily the bundles and pathways that connect those neural cells.

Prior research has indicated caffeine consumption may be associated with acute reductions in gray matter volume. But other research has also suggested caffeine could confer neuroprotective effects, slowing the cognitive decline associated with diseases such as Alzheimer’s and Parkinson’s.

The focus of this new study was to specifically investigate the effects of caffeine on gray matter volume in young and healthy subjects. One particular question the researchers wanted to answer was whether the influence of caffeine on gray matter was a result of the drug’s effect on sleep, as it has been shown that sleep deprivation or disruption can lead to acute reductions in gray matter.

Twenty subjects were recruited and tasked with two blinded 10-day programs. One period involved taking three tablets of caffeine each day and the other period involved placebo tablets. At the end of each program the participants' gray matter volume was measured through fMRI, and slow-wave sleep activity was measured through EEG.

The results revealed significant reductions in gray matter after 10 days of caffeine. These reductions were not seen after 10 days of placebo. And even more importantly, the study found no difference in slow-wave sleep activity between the placebo and caffeine periods. This suggests the gray matter reductions detected are not related to sleep disruptions but perhaps a unique feature of caffeine.

The effect of caffeine on the brain was noted as particularly relevant in the right medial temporal lobe. This area of the brain includes the hippocampus and is responsible for processes such as memory formation and spatial cognition.

Carolin Reichert, an author on the new study from the University of Basel, notes these caffeine-induced gray matter changes seem to recover quite quickly after caffeine consumption is ceased.

“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," says Reichert.

Reichert is also cautious to note this study does not imply caffeine consumption damages cognitive functioning. In fact, there has been a notable volume of recent research pointing to the contrary, showing caffeine seems to be somewhat neuroprotective, slowing cognitive decline in older subjects at high risk of conditions such as Alzheimer’s and Parkinson’s.

It is hypothesized these discordant results may be due to the new research’s focus on young healthy subjects compared to prior work looking at older subjects already displaying some degree of neurodegeneration or cognitive decline.

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

The new study was published in the journal Cerebral Cortex.

Source: University of Basel

8 comments
BIP
450mg of caffeine over 10 days!
If you drink regular 40ml espresso, that's about 30 mg of caffeine per cup. Even after 4 cups/day you get 1/3 of the study dosing. For sure, drinking 12 espresso cups a day will make me awake for 24h/day!
Worzel
Maybe, by ''shrinking'' brain matter, caffeine shortens the pathways, and speeds brain function?
LR
There is overwhelming anecdotal evidence from regular caffeine users where they claim ‘they can’t function properly until they’ve had their morning coffee’.
akarp
@LR: Yes, caffeine is very addictive. And withdrawal symptoms peak at ~24 hours after the last dose. (From Caffeine: How coffee and tea created the modern world by Micahel Pollan)
Trylon
@BIP, espresso is not the high-caffeine drink you seem to think it is. Each shot contains far less than a cup of regular coffee. 450mg is less than four cups of regular coffee. I know people who drink more than that every day.
Frank-Lee
Aaaahhhh, this seems to explain why my head has been getting bigger lately - I've been off coffee for a long while.....no need to see a shrink though, just do some caffeine....
Jinpa
Why no studies involving tea? Do older people drink more tea than coffee? Do they remember what they drank longer?
TomWatson
I feel like crap in the morning till I have 1 or 2 12 oz. cups of coffee, and then unload all of my crap. Just sayin'. I'm all in on coffee in the morning.