30/08/2025
A new study links drinking green tea with having fewer white matter lesions (WML) in the brains of Japanese seniors, potentially providing a level of protection against dementia. WML are abnormalities in the brain’s white matter (the part of the brain that contains nerve fibres responsible for communication between different brain regions) seen as hyperintense (bright) areas on MRI scans. They generally indicate chronic small vessel (microvascular) disease and are a relatively common finding in an older brain.
Researchers from institutions across Japan teamed up to analyse data on 8,766 volunteers over the age of 65, collected as part of a survey conducted between 2016 and 2018. Self-reported green tea and coffee consumption was cross-referenced against magnetic resonance imaging (MRI) brain scans, which measured overall brain volume and features of five different brain regions.
The scientists claimed: “This cross-sectional study found a significant association between lower cerebral white matter lesions and higher green tea consumption, but not coffee consumption, in older adults without dementia, even after adjusting for confounding factors”.
The observed effects were not large. Averaged out, those who had three cups of green tea per day had 3 percent fewer WML compared with those drinking one cup per day. Those who drank seven to eight cups per day had 6 percent fewer lesions, compared to those drinking one cup a day. One cup of tea was equivalent to approximately 200 mL.
WML, indicative of cerebral small vessel disease, are associated with vascular dementia and Alzheimer disease (AD). Larger WML were associated with more severe brain atrophy in patients with AD. Recently, a longitudinal study also identified WML as an independent risk factor for cognitive decline, even after accounting for traditional AD risk factors.
Given previous investigations linking green tea with lower blood pressure, and other studies associating lower blood pressure with a reduced risk of dementia, at least one mechanism responsible for the results could be cardiovascular. Interestingly, the scientists observed a significant relationship between increased green tea intake and decreased white matter lesions in individuals without the ApoE ε4 allele, but not in individuals with the ApoE ε4 allele (p for trend = 0.008 and 0.491, respectively).
I have maintained for some time now that my microcirculation phytonutrient diet will help to protect against brain WML. Now there is clear proof of this for green tea (a key element of the diet). The relatively small protection seen for green tea highlights that, as per the basis of the diet, one single intervention might not be enough on its own.
For more information see: https://www.medicalnewstoday.com/articles/green-tea-drinkers-have-fewer-brain-lesions-linked-to-dementia
and
https://pubmed.ncbi.nlm.nih.gov/39774601/
