NutriStack
Garlic Extract and Royal Jelly, a caution.
Royal Jelly and Garlic Extract both lower blood pressure through nitric-oxide-driven vasodilation (Royal Jelly additionally via ACE-inhibitory peptides), and both can modestly reduce clotting. Stacking them can cause an additive drop in blood pressure, with possible lightheadedness or dizziness, and a small additive increase in bleeding tendency.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- Garlic Extract and Royal Jelly
- Pair type
- Caution
- Evidence (highest tier)
- Emerging
- Source citations
- 3 sources
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Supplement
- Last verified
- May 30, 2026
Caution · Emerging evidence
Caution
What is happening. Royal Jelly and Garlic Extract both lower blood pressure through nitric-oxide-driven vasodilation (Royal Jelly additionally via ACE-inhibitory peptides), and both can modestly reduce clotting. Stacking them can cause an additive drop in blood pressure, with possible lightheadedness or dizziness, and a small additive increase in bleeding tendency.
Mechanism. Two overlapping mechanisms. (1) Additive blood-pressure lowering: Royal Jelly proteins yield ACE-inhibitory peptides (Ile-Tyr, Val-Tyr, Ile-Val-Tyr) and promote nitric-oxide-mediated vasodilation, producing measurable hypotensive effects in animal and some human data. Garlic Extract also lowers blood pressure largely through nitric oxide and hydrogen sulfide mediated vasorelaxation. Combined, they act on the same vasodilatory and renin-angiotensin pathways. (2) Additive antiplatelet effect: Garlic Extract inhibits platelet aggregation, and Royal Jelly has documented anticoagulation-potentiating activity, so the pair can also compound bleeding risk.
Recommendation. If you have normal blood pressure the combination is generally fine, but introduce them one at a time and stand up slowly at first to gauge any dizziness. If you take antihypertensive medication, monitor blood pressure at home for additive lowering and adjust under your clinician's guidance to avoid hypotension. Apply the same surgical-bleeding precaution as with other antiplatelet supplements: pause both 1 to 2 weeks before surgery. No specific dose ceiling is required for healthy users; use standard label doses of each.
Minimum separation. Spacing does not prevent the additive systemic effect; total daily intake is what counts, so monitoring matters more than timing.
Sources (3)
- Matsui T et al. Gastrointestinal enzyme production of bioactive peptides from royal jelly protein and their antihypertensive ability in SHR. J Nutr Biochem. 2002;13(2):80-86. PMID 11834223
- Rahman K et al. Dietary supplementation with aged garlic extract inhibits ADP-induced platelet aggregation in humans. J Nutr. 2000;130(11):2662-5. PMID 11053504
- Allison GL et al. Aged garlic extract and its constituents inhibit platelet aggregation through multiple mechanisms. J Nutr. 2006;136(3 Suppl):782S-788S. PMID 16484563
Stack Score
How this pair moves the number.
Effect on the composite score
If both Garlic Extract and Royal Jelly are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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