Decrease Seasonal Allergies

Rosmarinic acid, a plant chemical found in rosemary and plants in the mint family, is present in peppermint. Rosmarinic acid has been related to a reduction in allergic response symptoms such as runny nose, itchy eyes, and asthma. In a randomized 21-day trial of 29 adults with seasonal allergies, those who took an oral supplement containing rosmarinic acid reported fewer symptoms of itchy nose, itchy eyes, and other symptoms than those who took a placebo.

While it is uncertain if the quantity of rosmarinic acid present in peppermint is sufficient to impact allergy symptoms, there is some evidence that peppermint may alleviate allergy symptoms. In mouse research, peppermint extract decreased allergy symptoms including sneezing and itching nose.