Green tea makes you mentally fit
Until recently, the data on the possible advantages of tea for mental performance, especially for the dosage of tea, were rather thin. Now, however, pharmacology researchers from Tianjin University in China have carried out a comparative overview study to find out whether the studies conducted in recent years support a dose-dependent effect of tea on mental health.
Tea-drinkers watch out:
They identified studies on the topic from various medical science databases such as Pubmed, Embase and the Cochrane Library, with publication dates up to January 2017.
From 407 publications on the general topic, they found 17 studies with a total of 48435 participants who were consulted for analysis. Overall, they showed that people who consumed more tea were less likely than people who drank less tea to suffer from illnesses associated with mental disorders. The link between more tea and better mental health, however, was found only with certain types of tea. Green tea seemed to be the most effective way to protect mental performance, whereas black tea or oolong tea did not show a connection.
The scientists then analysed in more detail whether not only ‘little’ and ‘much’ tea had distinguishable effects, but whether the dosage was really relevant. In fact, it was found that an increase in the amount of tea was directly associated with a decrease in the risk of mental illness. A more of 100 ml/day led to a risk reduction of 6 %, 300 ml more tea per day led to a 19 % lower risk and a half litre per day additionally reduced the risk for mental performance disorders by 29 %.
In summary, the studies of recent years and decades show that green tea in particular can be of significant benefit for mental health. The more green tea is drunk, the lower the risk of mental disorders, including dementia.
Other studies had already shown the positive effects of green tea on sleep disorders or depression. So there are even more good reasons to enjoy a cup of tea regularly. However, caution is also advised here: depending on the type of tea, a high amount of fluoride may be contained in the tea, which in turn can lead to health problems – green tea should therefore not be consumed excessively, despite all the positive effects.
Liu X, Du X, Han G, Gao W. Association between tea consumption and risk of cognitive disorders: A dose-response meta-analysis of observational studies. Oncotarget. 2017;8(26):43306-43321. doi:10.18632/oncotarget.17429 https://www.ncbi.nlm.nih.gov/pubmed/28496007