Green tea consumption reduces brain lesions

Proceeding from a recent article, News Medical Life Sciences highlights the potential benefits of green tea consumption in reducing the risk of cerebral white matter lesions, which are often associated with dementia. 

Tea and coffee, two of the most widely consumed beverages globally, contain several compounds with neuroprotective effects, including caffeine, polyphenols, and vitamins. Green tea, black tea, and coffee also have epigallocatechin gallate, theaflavins, chlorogenic acid, and caffeic acid, all of which possess antioxidant and anti-inflammatory qualities.

Numerous epidemiological studies have suggested that drinking tea or coffee may help reduce the risk of age-related cognitive decline. Dementia, a neurodegenerative disease leading to cognitive deterioration, is linked to various structural changes in the brain, such as brain atrophy, hippocampal shrinkage, and an increase in lesions in the cerebral white matter.

Previous research has shown that green tea consumption is linked to a reduction in annual hippocampal atrophy, while regular coffee consumption can help increase brain cortex thickness. Building on these findings, the current study investigates the effects of green tea and coffee consumption on cerebral white matter lesions, hippocampal volume, and total brain volume in an older Japanese population without dementia.

The study involved 8,766 individuals from the Japan Prospective Studies Collaboration for Aging and Dementia (JPSC-AD), a community-based research project on dementia conducted across eight regions in Japan. Participants were recruited between 2016 and 2018.

Brain magnetic resonance imaging (MRI) was performed on participants to evaluate cerebral white matter lesions, hippocampal volume, and total brain volume. Additionally, all participants filled out a Food Frequency Questionnaire to report their daily consumption of green tea and coffee.

Around 91 per cent of participants drank green tea, and 82 per cent consumed coffee. Those who consumed more green tea daily were found to have higher levels of regular exercise, better cognitive function, and lower rates of smoking, alcohol consumption, and depression. On the other hand, participants with higher coffee intake had higher rates of diabetes, smoking, and cardiac issues.

The analysis accounted for various potential confounding factors, including age, sex, study location, education level, apolipoprotein E (ApoE) ε4 carrier status, hypertension, body mass index (BMI), serum low- and high-density lipoprotein cholesterol levels, regular physical activity, and smoking and drinking habits. The results showed a dose-dependent relationship, where individuals consuming 600–1500 ml of green tea daily had significantly fewer cerebral white matter lesions compared to those with lower consumption levels.

After adjusting for these factors, the study found that higher daily green tea consumption was linked to a reduction in cerebral white matter lesions. However, no significant associations were observed between green tea intake and hippocampal or total brain volumes.

Regarding coffee consumption, no significant relationships were found with cerebral white matter lesions, hippocampal volume, or total brain volume. This contrasts with previous studies that have suggested beneficial effects of coffee on brain health in other populations.

By Naila Huseynova