Last verified: today
Garlic
Also known as: Allium sativum, allicin, garlic extract, aged garlic extract, garlic oil, garlic powder
Evidence under review. — Not yet rated
Garlic lowers blood pressure, improves cholesterol, and reduces blood sugar in multiple clinical trials.
-
What it does
Garlic is a culinary plant whose active compound, allicin, has measurable effects on cardiovascular and metabolic health. Clinical trials show it can meaningfully lower blood pressure, reduce LDL...
-
Evidence quality
Evidence base hasn't been formally rated yet. See research below.
-
Clinical dose
500–1000 mg extract daily (standardized to 2–3 mg allicin) or 5 g raw garlic twice daily based on study doses
-
Found in
AG1 (Athletic Greens), Fortheageless, Life Extension Aged Black Garlic and 4 more
What the Science Says
Garlic is a culinary plant whose active compound, allicin, has measurable effects on cardiovascular and metabolic health. Clinical trials show it can meaningfully lower blood pressure, reduce LDL cholesterol and triglycerides, raise HDL cholesterol, and improve fasting blood sugar — particularly in people with elevated cardiovascular risk or metabolic syndrome. Effects are typically seen within 4–8 weeks at standardized extract doses of 500–1000 mg daily.
What It Doesn't Do
Not a replacement for blood pressure or cholesterol medication. Won't cure diabetes on its own. No solid human evidence it boosts testosterone or directly burns fat. Animal and lab studies on constipation and liver protection are interesting but not proven in humans yet.
Evidence-Based Benefits
Lowers systolic and diastolic blood pressure in people at risk for hypertension.
Moderate EvidenceEffective at: 500–1000 mg standardized extract daily for 8 weeks
Supporting studies (click to view on PubMed):
Reduces LDL and total cholesterol while raising HDL in people with mildly elevated levels.
Moderate EvidenceEffective at: 500–1000 mg standardized extract daily for 8 weeks
Supporting studies (click to view on PubMed):
Reduces fasting blood sugar in women with PCOS and metabolic syndrome.
Moderate EvidenceEffective at: 500 mg (2–3 mg allicin) twice daily for 8 weeks
Supporting studies (click to view on PubMed):
Improves erectile function as an add-on to tadalafil in men who don't respond to the drug alone.
Weak EvidenceEffective at: 5 g raw garlic twice daily for 4 weeks
Supporting studies (click to view on PubMed):
Reduces CRP, a key marker of inflammation, in women with metabolic syndrome.
Moderate EvidenceEffective at: 500 mg (2–3 mg allicin) twice daily for 8 weeks
Supporting studies (click to view on PubMed):
Absorption & Bioavailability
Moderate — allicin is unstable and degrades quickly; standardized extracts and enteric-coated capsules improve consistency. Raw garlic bioavailability varies widely based on preparation and individual gut metabolism.
Red Flags to Watch For
- May interact with blood-thinning drugs like warfarin — one review flagged a garlic-saquinavir interaction, and anticoagulant effects are a known concern
- Garlic supplements vary widely in allicin content; products without standardization may deliver little active compound
- High doses can cause GI upset, heartburn, and bad breath — not just a cosmetic issue, it signals systemic absorption
- Pregnant women and people on antiretroviral therapy (e.g., saquinavir) should consult a doctor before supplementing
- Most dramatic results in provided trials were in people with existing metabolic conditions — effects in healthy adults may be smaller
Products Containing Garlic
See how Garlic is used in these analyzed products:
AG1 (Athletic Greens)
Supplement
Fortheageless
Supplement
Life Extension Aged Black Garlic
Supplement
Supergreen Tonik
Supplement
Texas SuperFood Original Capsules
Supplement
Nitro Wood™ Magnum
Supplement
TestoPrime
Supplement
Research Sources
- PubMed
- NIH DSLD
This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-05-25