Compound or practice · Supplement
Garlic
Real, modest blood-pressure lowering and small lipid effects — a legitimately useful kitchen cardiovascular supplement.
- Overall grade
- Grade B
- Last revised
- 2
- graded outcomes
- 0
- references listed
A structured monograph in Prometheus's bundled library. Its grades are the monograph's own reading of the evidence, not a peer-reviewed review.
2 at grade B · 1 at grade C — 3 graded rows
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Blood pressure (hypertensive)Evidence grade B
Several mmHg
Moderatehigh
- LDL cholesterolEvidence grade C
Minor
Smallmixed
Conditions
How the entry reads its effect on diagnosed conditions: the direction first, then the grade. Never a substitute for the person who treats you.
- Hypertension May improveEvidence grade BModest additive loweringGrade B
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Thin evidence: LDL cholesterol (grade C).
- Caution with Anticoagulants (warfarin): Antiplatelet action — additive bleeding risk.
- Caution with Blood-pressure medications: Additive blood-pressure lowering.
Interactions
Documented pairings with supplements and medicines. A medicine on this list is a conversation for whoever prescribes it.
Anticoagulants (warfarin)Caution
Antiplatelet action — additive bleeding risk.
Blood-pressure medicationsCaution
Additive blood-pressure lowering.
The evidence in words
What it is
Garlic supplements deliver allicin and related sulfur compounds; aged garlic extract is a common standardized form. It is one of the better-studied culinary cardiovascular botanicals.
How it works
Garlic's organosulfur compounds promote vasodilation (partly via hydrogen sulfide and nitric oxide) and modestly influence lipids and platelet function.
What the evidence shows
Meta-analyses show a genuine, if modest, systolic blood-pressure reduction (on the order of several mmHg) in hypertensive people, plus small LDL improvements. Antiplatelet effects are real. Immune/cold data are weaker. A sensible, cheap adjunct for blood pressure.
How to use it
Aged garlic extract or standardized allicin products dosed to deliver several mg of allicin potential daily; benefits accrue over weeks.
Safety & interactions
Odor and GI upset; antiplatelet action adds bleeding risk with anticoagulants and around surgery. warfarin — Antiplatelet action — additive bleeding risk. antihypertensives — Additive blood-pressure lowering.
Bottom line
A rare kitchen supplement with real cardiovascular data: modest blood-pressure and lipid benefits. Mind the bleeding interaction if you're on blood thinners.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Standard
- Aged garlic extract / standardized allicin daily.
Related reading
Entries that share this one's tags or conditions.
- Cocoa Flavanols for Blood pressureEvidence grade B — Modest reductionEvidence grade B
- Garlic for Blood pressure (hypertensive)Evidence grade B — Several mmHgEvidence grade B
- Garlic for HypertensionEvidence grade B — Modest additive loweringEvidence grade B
- Garlic for LDL cholesterolEvidence grade C — MinorEvidence grade C
Sources
This entry lists no references of its own.
Last revised . A grade is this entry's reading of the evidence, not medical advice.