Matcha May Reduce Allergy Sneezing By Quieting The Brain’s Sneeze Circuit

Allergy season sends millions of Americans reaching for antihistamines, nasal sprays, and whatever else promises to stop the sneezing. A new study suggests something already sitting in a lot of kitchen cabinets might help, and it may work through a different biological pathway than most current allergy medications.

Researchers at Hiroshima University found that mice with induced allergic rhinitis sneezed significantly less after receiving matcha extract. Standard allergy medications work by suppressing the immune system, blocking the antibodies and inflammatory cells that drive allergic reactions. Matcha, in this study, left most of that untouched. Instead, it appeared to act on the nervous system, dramatically reducing activity in a brainstem relay involved in the sneeze reflex. Published in npj Science of Food, the research is preliminary and conducted in mice, but it points to a specific biological mechanism that current allergy treatments do not target.

For the tens of millions of Americans with allergic rhinitis, that matters. Existing treatments are effective but come with trade-offs like drowsiness, nasal dryness, and the need for daily medication. A compound that works through an independent pathway, one that calms the neural reflex rather than the immune cascade, could one day change that calculus.

How Matcha Was Put to the Allergy Test

Scientists first immunized female lab mice with ovalbumin, a protein derived from egg whites commonly used to trigger allergy-like responses in the lab, and later exposed them to it through nasal challenges to provoke allergic symptoms including sneezing. Over five weeks, mice received weekly immunization injections followed by daily nasal exposures. A separate group also received matcha extract delivered directly into the stomach three times per week, with an extra dose 30 minutes before each nasal exposure.

Matcha for the study came from standard-grade leaves harvested in Kyoto’s Uji region and was prepared as a hot-water extract at approximately 65 degrees Celsius, administered to the mice along with the remaining powder residue. That last detail matters: when people drink matcha, they consume the entire powdered leaf rather than just what dissolves, which delivers a broader range of active compounds than a standard cup of steeped green tea provides.

Sneezes were counted in five-minute windows after each allergen exposure, and researchers separately tested how the mice responded to histamine, a chemical the body releases during allergic reactions. Blood antibody levels, nasal inflammatory cells, gut bacteria, mast cell activity, and immune T-cell behavior were all tracked to map out precisely where matcha was, and was not, having an effect.

Matcha Reduced Allergy Sneezing Without Disrupting Key Immune Responses

Matcha-treated mice sneezed significantly less in direct response to the allergen. Most standard immune markers were unaffected: IgE antibodies, the proteins the immune system produces in response to allergens, remained unchanged, as did nasal white blood cells, mast cell responses, and most T-cell activity. A separate skin test confirmed matcha had no effect on IgE-driven immune processes. Histamine-triggered sneezing also trended lower in matcha-treated mice, though that difference did not reach statistical significance.

With the primary immune pathways accounting for little to none of the effect, researchers turned their attention to where the reduction in sneezing was actually coming from.

How Matcha May Quiet the Brain’s Sneeze Circuit

To investigate whether matcha was influencing the nervous system directly, researchers focused on a small brain structure called the spinal trigeminal nucleus caudalis, or Sp5C, a brainstem relay station for sensory signals from the nose and face that plays a central role in the sneeze reflex. When its neurons activate, they produce a protein called c-Fos that researchers can detect under a microscope, making it a precise readout of whether the sneeze circuit is firing.

In untreated mice given histamine nasally, the Sp5C showed a strong surge in c-Fos activity. In mice pretreated with matcha, that activity was dramatically reduced, falling back toward levels seen in unstimulated animals. According to the researchers, matcha treatment nearly abolished histamine-induced c-Fos expression, “reducing it to basal levels, suggesting direct suppression of neural mechanisms underlying the sneezing reflex.”

Matcha contains compounds such as L-theanine, caffeine, and EGCG, a well-studied green tea antioxidant, that have been linked to nervous system activity and stress reduction in previous research, which could help explain the effect. Sneezing is a sensory nerve reflex, but autonomic signals, the ones that govern involuntary functions like heart rate and digestion, also shape how intensely it fires. Researchers believe the interplay between those systems may be involved, though which specific compound is responsible, and whether the mechanism is purely neural or involves some mix of neural and immune factors, remains to be worked out.

A New Path for Allergy Relief

Matcha is not about to replace an antihistamine. All of this evidence comes from mice, and the dose used in the study was far higher than what a person would consume from a typical cup. Human allergic rhinitis is shaped by genetics, years of allergen exposure, and environmental factors a mouse model cannot replicate. Human trials will be needed before any clinical conclusions can be drawn.

What this research does offer is a new direction. Allergy science has long focused on calming the immune system, and for good reason. But for patients who cannot tolerate standard medications or want options beyond a daily pill, a common food compound that may ease symptoms by acting on the brain rather than the immune system is a legitimate avenue worth pursuing.

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Disclaimer: This article is based on preliminary animal research and is intended for informational purposes only. Results from mouse studies do not always translate to humans. Matcha is not a medical treatment for allergic rhinitis or any other condition. Consult a qualified healthcare provider before making any changes to your allergy management plan.

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