Small daily doses of peppermint oil reduce systolic blood pressure in adults
A study of 40 adults with mildly elevated blood pressure found that taking 100 microliters of peppermint oil twice daily for 20 days lowered systolic blood pressure by an average of 8.5 mmHg, while a placebo group showed little change. The inexpensive oil was well-tolerated. Researchers suggest it could serve as a simple additional option for managing high blood pressure.
The randomized controlled trial enrolled 40 adults aged 18 to 65 who had prehypertension or stage 1 hypertension. Participants received either 100 microliters of peppermint oil twice daily or a peppermint-flavored placebo lacking the active oil, with the treatment period lasting 20 days. Beyond systolic pressure, researchers monitored diastolic readings, heart rate, body measurements, blood markers, mental well-being, and sleep quality, though systolic pressure served as the primary outcome.
Peppermint's active compounds include menthol and flavonoids, which may underlie the observed effect. The study appears in PLOS One and was led by Dr. Jonnie Sinclair at the University of Lancashire. Because the oil is inexpensive and produced no notable side effects, the authors frame it as a potentially practical adjunct for blood pressure management, though the small sample size and short duration warrant cautious interpretation.
If replicated in larger trials, this finding could offer a low-cost supplementary option for the millions of adults with mildly elevated blood pressure who cannot tolerate or afford conventional medications. A simple dietary intervention may also encourage earlier engagement with blood pressure management, potentially reducing long-term cardiovascular risk. However, the modest sample size and short timeline mean the effect size and durability remain uncertain, and peppermint oil would likely complement rather than replace established treatments.