A recent study into the effect of green tea on cognitive performance reports positive results with implications for the treatment of Alzheimer’s & dementia.
Over the last 2 decades a plethora of studies have teased us with the possible health benefits of consuming green tea, everything from raised energy levels, weight management and even hair growth have been attributed to these miracle leafs. Today we face the challenges of an aging population like never before and with this the increase in age related illnesses such as Alzheimer’s and dementia.
The benefits of drinking green tea on concentration and clarity of mind are nothing new, 15th century Zen Buddhist monks knew about these properties and exploited them fully to stimulate an enhanced meditative state. Today we have the ability to view the effects of green tea on the brain using MRI (magnetic resonance imaging) technology and new research carried out at the University of Basel in Switzerland has used this MRI technology to investigate what happens to the brain when we consume green tea.
This study published by Prof. Christoph Beglinger from the University Hospital of Basel and Prof. Stefan Borgwardt from the Psychiatric University Clinics in March 2014 in the academic journal Psychopharmacology provides the first visible evidence that green tea extract enhances the brain’s cognitive functions and in particular that of the working memory.
What did they do?
In this study 12 healthy male volunteers received a soft drink containing several grams of green tea extract before they solved working memory tasks. All the volunteers were carefully screened for amphetamines, benzodiazepines, cocaine, methamphetamine, opiates, and THC . They were also subjected to a clinical interview to exclude psychiatric or physical illness or a family history of psychiatric illness. All were non smokers and abstained from any substance use for the duration of the study including alcohol, caffeine, green tea products, and citrus juices.
Each volunteer was then given either a milk whey-based soft drink containing 27.5 g of green tea extract or a milk whey-based soft drink without green tea extract. Researchers then observed the effects using MRI.
What did they find?
The study concluded that “green tea extract enhances functional connectivity from the parietal to the frontal cortex during WM processing in healthy controls.” 1 What does that mean? Well, basically green tea had a positive effect on the brain’s ability to perform the tasks they were given. Green tea therefore induced improvements in cognitive performance.
But the researchers went further and suggested that these results “may provide a promising tool to assess the efficacy of green tea or other compounds for the treatment of cognitive impairments in psychiatric disorders such as dementia.” They stated that they found “a strong trend toward improved performance.” 1
The implications for cognitive illnesses
The Alzheimer’s society estimates that by 2015 there will be 850,000 people in the UK suffering from Alzheimer’s and 1 million people in the UK likely to be suffering from dementia by 2025 2 . These numbers are quite staggering and with the cost of dementia to the UK hitting £26 billion per annum any research taking positive steps towards a treatment must be welcomed. If green tea can contribute to the management, reduction or treatment of Alzheimer’s or dementia then this could be the starting point.
It’s worth noting that switching to green tea is unlikely to tackle the problem alone, but the health benefits of green tea are well documented across time. One only needs to look at those countries where green tea is a staple in daily diets to see lower instances of cognitive illnesses such as Alzheimer’s, Japan is just one example.
The immediate implication of this study will likely be that it spurs further research into the contribution green tea could make to tackling cognitive illnesses.
A healthy dose of reality
With all such studies it is important to put things in perspective. Yes, the result was positive and could hint at future advances but this is one of only a handful of studies in this area to date and the results did have some limitations. Although the MRI evidence shows a positive effect, the researchers reported that they “observed no significant effect of green tea consumption on task performances”. The ultimate conclusion here is that more studies into the possible use of green tea extracts to treat conditions such as Alzheimer’s and Dementia are needed.
If you’d like to learn more about the science behind green tea and matcha green tea in particular then visit matchahq.com where we take a scientific look at the health benefits of switching to matcha green tea including recipes and advice on how best to add green tea into your diet.
- Schmidt A, Borgwardt S, Hammann F, Wölnerhanssen B, Meyer-Gerspach A C, Drewe J, Beglinger C (2014) Green tea extract enhances parieto-frontal connectivity during working memory processing. Psychopharmacology March 2014