Garlic
The one kitchen herb with a blood pressure effect you can compare to medication. Cutting it and waiting is half the work.
How to use it
Raw, or added late and briefly heated. In dressings, through guacamole, over roasted vegetables.
The best version
A fresh bulb with tight skin and hard cloves, not the chopped kind from a jar. A green shoot inside means it is old, and the shoot itself can come out.
How to prepare it
Chop or crush it and leave it for ten minutes before it goes near heat. The enzyme that makes the active sulphur compound is only released by the damage and needs a moment, and heat stops it dead.
What it does
In people with high blood pressure, garlic does what a pill does. Across 12 trials with 553 participants between them, systolic pressure fell by an average of 8.3 mmHg, and across 8 trials with 374 participants diastolic pressure fell by 5.5 mmHg.
Watch out
Those trials used garlic preparations, mostly aged garlic extract, and not a clove out of the pan. They were also run in people who were already too high: at a normal blood pressure there is nothing to lower.