A Cheap Bottle of Peppermint Oil Just Outperformed Expectations on Blood Pressure

Researchers at the University of Lancashire ran a small trial on something most people already have a version of in their kitchen cupboard. Forty adults with mildly high blood pressure took 100 microliters of peppermint oil twice a day for 20 days. By the end, their average systolic blood pressure had dropped 8.5mmHg. The placebo group barely moved.

That's a meaningful drop for a condition usually managed with prescription medication, and it came from an oral peppermint oil supplement, not peppermint tea, which contains far less menthol and far fewer of the compounds researchers think are doing the work here. The findings were published in PLOS One.

The researchers are upfront that this is a pilot study: 40 people over 20 days is a promising early signal, not proof that'll change medical guidelines tomorrow. Peppermint oil can also interact with other medications through liver enzymes, so it's not something to just start taking alongside existing blood pressure treatment without checking with a doctor first.

Still, for people with borderline-high readings who aren't yet on medication, a cheap, well-tolerated supplement showing a real effect in a controlled trial is worth paying attention to, especially compared to how much research into blood pressure treatment usually costs to develop and how expensive the resulting drugs often are.