A new study suggests that matcha, the finely ground powder used to make traditional Japanese green tea, may influence the body’s sneezing response during allergic reactions. In experiments with mice, researchers found that matcha reduced sneezing triggered by allergy exposure.
The findings come from scientists at Hiroshima University and were published March 5 in the journal npj Science of Food. The work focused on allergic rhinitis, a condition commonly known as hay fever that causes sneezing, congestion and nasal irritation.
“Human studies suggest green tea may relieve allergic rhinitis, but how it works is unclear,” said study author Osamu Kaminuma of Hiroshima University’s Research Institute for Radiation Biology and Medicine.
To explore the question, the research team used mice engineered to develop symptoms similar to allergic rhinitis. The animals received matcha tea two to three times per week for more than five weeks, along with an additional dose shortly before being exposed to an allergen.
The mice that received matcha sneezed less than expected after allergen exposure. But the researchers found something more surprising when they examined how the effect occurred.
Instead of changing the immune signals typically involved in allergic reactions, matcha appeared to act on the nervous system.
“Oral matcha reduced sneezing without clearly changing major immune markers. Instead, it strongly suppressed brainstem neuronal activation linked to the sneezing reflex,” Kaminuma said.
Allergic reactions often involve antibodies called immunoglobulin E, or IgE, which activate immune cells known as mast cells and trigger the release of histamine and other inflammatory chemicals. Those pathways drive many of the familiar symptoms of allergies.
In the new study, however, matcha did not appear to significantly affect those immune responses. Instead, the researchers observed changes in activity in a brain region involved in controlling the sneeze reflex.
Specifically, the team measured expression of a gene called c-Fos, which scientists use as a marker of neural activation. When mice experienced allergy symptoms, c-Fos activity increased in a brainstem region known as the ventral spinal trigeminal nucleus caudalis. Matcha treatment reduced that activity closer to normal levels.
The findings suggest that compounds in matcha may influence how the brain processes signals that trigger sneezing.
However, the research was conducted in animals, and the results do not show that drinking matcha would reduce allergy symptoms in people. The researchers say human studies are needed to determine whether the same effects occur outside the laboratory.
“The goal is an evidence-backed, food-based option that complements standard care for allergic rhinitis symptoms,” Kaminuma said.
For now, the study offers an early glimpse into how compounds in foods like green tea might interact with both the immune system and the nervous system. Scientists are increasingly interested in these kinds of connections as they explore how diet may influence inflammation, brain signaling and other biological processes.
The researchers reported no competing interests. The study was conducted by scientists at Hiroshima University and published in the peer-reviewed journal npj Science of Food.