Experiments on mice with symptoms similar to allergic rhinitis show that matcha can help reduce sneezing and irritation.
A new study in NPJ Science of Food suggests that matcha, the finely ground green tea powder long associated with Japanese cuisine, may help reduce the symptoms of nasal allergies.
Matcha, a staple food in Japan, is produced from specially grown green tea leaves, which are dried and ground until they become a powder bright green. Widely consumed as a drink and used in foods, matcha is rich in antioxidants and amino acids, compounds previously associated with benefits such as improved cardiovascular health, improved brain function and reduced inflammation.
Now, researchers led by Osamu Kaminuma of Hiroshima University have explored whether matcha could also play a role. role in alleviating allergic rhinitis. Their findings point to a new mechanism behind its potential effects.
In the study, scientists tested matcha on mice genetically engineered to develop symptoms similar to allergic rhinitis. Over a period of more than five weeks, the animals were given matcha tea several times a week, as well as an additional dose just before exposure to the allergens.
The results showed a clear reduction in sneezing among rats treated with matcha. However, what caught our attention was the way in which this improvement occurred. Traditional allergic responses, typically mediated by immunological components such as immunoglobulin E (IgE), mast cells and T cells, have remained practically unchanged, says .
Instead, researchers found that matcha appears act on the nervous system. Specifically, it suppressed activity in a brain stem region associated with the sneeze reflex. This was measured by reduced expression of the c-Fos gene, known to signal neural activation in response to strong stimuli, including allergens.
In untreated rats, exposure to allergens caused a sharp increase in activity of c-Fos in the brain region that controls sneezing. In contrast, the matcha-treated rats had near-normal levels, suggesting that the green tea powder attenuated the neural signals responsible for triggering the reflex.
The findings highlight a potentially effective new way to manage allergy symptoms, not by directly altering the immune system, but by change the way the brain responds to irritation.
Despite the promising results, the researchers caution that the study was carried out on animals and that more research is needed to determine whether the same effects apply to humans.
