Study Finds Peppermint Oil May Lower Blood Pressure Within Just 20 Days

A small daily dose of peppermint oil may help lower mildly elevated blood pressure, according to new research from the University of Lancashire.

The study, published in PLOS One, found that taking 100 microliters of peppermint oil twice daily for 20 days reduced systolic blood pressure by an average of 8.5 mmHg in adults with prehypertension or stage 1 hypertension.

High blood pressure is a major preventable risk factor for cardiovascular and metabolic diseases, including heart disease and stroke. Current treatment generally focuses on lifestyle changes and, when necessary, prescribed medications.

Researchers enrolled 40 adults aged 18 to 65 and randomly assigned them to receive either peppermint oil or a peppermint-flavoured placebo. Participants in the peppermint oil group experienced a reduction in blood pressure, while those receiving the placebo showed no meaningful change.

Peppermint naturally contains compounds such as menthol and flavonoids, which may contribute to its biological effects. However, the precise mechanism through which peppermint oil could influence blood pressure remains unclear.

The researchers also examined several other health measures, including diastolic blood pressure, heart rate, body measurements, blood test results, sleep quality and mental well-being. The study was designed primarily to assess the potential effect on blood pressure.

The findings raise the possibility that peppermint oil could become a simple, inexpensive approach for managing mildly elevated blood pressure. However, the researchers caution that the study involved only a small number of participants and lasted just 20 days. Larger, longer-term clinical trials will be necessary to confirm the results, determine whether the blood pressure reduction persists and establish the appropriate dose and safety profile.

Researchers say peppermint oil could potentially complement established approaches if future studies confirm its benefits. However, people with hypertension should not stop or replace prescribed medication with peppermint oil without consulting a healthcare professional.

REFERENCE: Jonathan Sinclair, et al.; Effects of peppermint (Mentha x piperita L.) oil on cardiometabolic outcomes in patients with pre- and stage 1 hypertension: A placebo randomized controlled trial. PLOS One, 2026; 21 (4): e0344538 DOI: 10.1371/journal.pone.0344538