According to the Daily Mail, Swiss researchers in this study gave 20 healthy young people three servings of 150 mg of caffeine per day for 10 days. This amount of caffeine is equal to drinking four or five small cups of brewed coffee a day.
At the end of these 10 days, the researchers measured 450 mg of caffeine per day by measuring the volume of gray matter in the brain using a brain scan, and they found a reduction in the volume of gray matter in the brains of the subjects.
In this study, there was a significant reduction in brain gray matter, especially in the right temporal lobe, including the hippocampus, an area of the brain that is essential for memory consolidation.
Gray matter is found in the outermost layer or cortex of the brain and is involved in information processing. Gray matter refers to parts of the central nervous system that are primarily composed of nerve cells, while white matter refers primarily to nerve pathways.
However, in this study, this effect seemed to be temporary, so that after only 10 days of stopping any caffeine, these changes were reversed.
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