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Garlic

A heart-friendly bulb — real, if modest, effects on blood pressure and cholesterol.

Reviewed by Bodil Isaksson, Licensed Biomedical Scientist (Sweden)Last reviewed July 2026Food guide

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Garlic is one of the better-evidenced culinary medicines for the heart. Its organosulfur compounds, chiefly allicin, are formed when you crush or chop it.

Key takeaways

  • Meta-analyses: garlic lowers blood pressure (~5 mmHg systolic, ~2.6 mmHg diastolic) in people with hypertension.1
  • It also modestly improves cholesterol and may support immune function.1
  • Crush and rest chopped garlic ~10 minutes to form allicin; aged garlic extract is a standardised, low-odour option.
  • Safe as food; high doses can thin the blood (caution before surgery / with anticoagulants) and cause odour and reflux.

What it is

Garlic (Allium sativum) produces allicin and related sulfur compounds when its cells are damaged by crushing or chopping — these are behind most of its cardiovascular effects.

The evidence

Updated meta-analyses show garlic supplements significantly reduce blood pressure in hypertensive people, regulate cholesterol (lowering total/LDL, raising HDL) and modulate immune markers.1 Effects are real but modest — a helpful adjunct, not a replacement for medication.

Dose & how to use

Culinary garlic daily, crushed and rested; or aged garlic extract (standardised) for consistent dosing with less odour.

Safety & who benefits

Safe for most. Of interest for blood pressure and cholesterol. Caution with blood thinners and before surgery; it can also irritate reflux.

Bottom line: a legitimately heart-friendly spice with modest, repeatable blood-pressure and cholesterol effects — crush it, rest it, and eat it often.

References

Educational summary, not a prescription.

  1. Ried K. Garlic lowers blood pressure in hypertensive subjects, improves arterial stiffness and gut microbiota: a review and meta-analysis. 2020. pmc.ncbi.nlm.nih.gov

This article summarises nutrition science for education and is not a substitute for individual medical advice.