Diet and lifestyle can reverse the damage caused by aging, both in the body and in the mind. And, among all the foods and drinks that have been shown to be particularly beneficial, green tea certainly plays an essential role, especially as regards brain health. Green tea, in fact, thanks to the synergy of substances that compose it, has been shown to improve memory, concentration and learning ability and to reduce the risk of dementia thanks to various mechanisms. To understand the action processes of green tea on brain health, a team of Japanese scientists developed a research whose results were published in the journal Nutrients a few weeks ago (Unno et al, Nutrients, 2021).
Aging, diet and lifestyle
With age, changes occur in our body that can lead to the development of arteriosclerosis, diabetes, cardiovascular problems, obesity, hypertension and even memory loss. However, following dietary and lifestyle guidelines have been found to reduce the risk of these diseases. Among the recommendations, there is also that of drinking green tea. Green tea is a drink obtained from the infusion of the leaves of the Camellia sinensis plant that have not undergone fermentation. When we talk about the health properties of green tea, we tend to refer only to epigallocatechin gallate, which is a powerful antioxidant. In reality, green tea is a synergy of substances that act for well-being. In order to fully understand this synergy, the article we are talking about today was published.
The action of green tea, activation of neurons
First of all, epigallocatechin gallate is certainly one of the substances with which green tea acts on the brain. What the scientists observed is that when we drink green tea, a small part of epigallocatechin gallate immediately enters the bloodstream and reaches the brain where it works by activating and supporting neurons. Instead, most of this substance is processed by the intestinal microbiota, which in turn produces other substances that will reach the brain at a later time. These substances, too, as scientists have observed, affect brain health by activating neurons. Therefore, the beneficial action of green tea is partly immediate and partly over a longer period.
The action of green tea, its anti-stress properties
But green tea also contains other beneficial substances, such as theanine and arginine. These two amino acids work by counteracting stress. Research has shown that prolonged stress can speed up brain aging. Therefore, theanine and arginine work by counteracting stress and therefore the aging of the brain, protecting it from the risk of developing dementia.
How to choose green tea for brain health
Drinking one to five cups of green tea has been shown to improve memory, concentration and cognitive function and reduce the risk of dementia. Not only that, it is never too late to introduce green tea into your diet because benefits have been observed at all ages and not only in those who have been drinking this drink for several years, the important thing is to start! Finally, not all green teas are created equal. Shadow teas, such as gyokuro, which is a Japanese tea, are the teas with the highest amounts of theanine and therefore more capable of protecting the brain from damage caused by stress. In fact, the protective action of theanine is limited if the green tea contains less amino acids but more caffeine. In general, high grade, and therefore more valuable, green teas contain high amounts of theanine. It has been observed, indeed, that the lower the water infusion temperature, and this happens with high grade teas, the lower the amount of caffeine released.