Resveratrol & Quercetin
Resveratrol + Quercetin,
decoded honestly.
Two longevity-research polyphenols — and an industry full of inflated numbers. This is a plain-English look at the science, the law, and how to read a label so every milligram actually means something.
Two polyphenols, one capsule
Both are plant compounds widely studied in longevity research — and they're often paired for a reason.
Resveratrol
A polyphenol found in grape skins, red wine and Japanese knotweed. The form that matters is trans-resveratrol — the biologically active isomer studied for its role in cellular and longevity pathways (including sirtuins). “Total resveratrol” on a label can include the inactive cis-form and other material.
Quercetin
A bright-yellow flavonoid found in onions, apples and capers. It's a polyphenol in its own right and is frequently paired with resveratrol in longevity research. In our capsule it does double duty — it's an active ingredient and what gives Eternal Resveratrol its natural yellow colour.
“Trans” is the part that counts
The single biggest source of confusion on a resveratrol label is the difference between total and trans.
📦 Total resveratrol
The headline number on most labels. It can include the inactive cis-isomer and other plant material that came along for the ride. A big “total” figure tells you how much stuff is in the capsule — not how much is actually working.
⚡ Trans-resveratrol
The active isomer that research is actually interested in. This is the number worth checking. When a label only quotes “total” — or doesn't state purity at all — you can't know the active dose you're really getting.
What you're actually allowed
Trans-resveratrol is an authorised novel food in the UK/EU. For adults, food supplements in capsule or tablet form have a maximum of 150 mg per day — referenced to the active trans-resveratrol, not “total”.
Maximum for adults — food supplements (capsule/tablet form), as defined in Directive 2002/46/EC.
| Food category | Maximum levels |
|---|---|
| Food Supplements as defined in Directive 2002/46/EC for adult population (capsule or tablet form) | 150 mg/day |
Reference: UK Food Standards Agency authorisation for trans-resveratrol.
The label decoder
Here's the trick the “1000 mg!” labels don't want you to do. Move the sliders — or pick a real-world example — and watch how much of that big number is actually active trans-resveratrol.
Filler — or a second active?
Here's a problem nobody mentions: 150 mg of pure trans-resveratrol is a tiny amount of powder. To make a consistent, fillable capsule you have to add something. Most brands add inert filler. We added an active.
Resveratrol × Quercetin
They aren't in the same capsule by accident. Both are polyphenols studied in the same corner of longevity research — and they're commonly combined.
Resveratrol
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🧬Same research lane. Both are polyphenols explored for their roles in cellular and longevity pathways — they're frequently studied together rather than alone.
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🤝A classic pairing. Quercetin is one of the most common companions to resveratrol in formulations and studies, which is why you'll often see the two named side by side.
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🟡It earns its place. Rather than an inert bulking agent, quercetin is an active polyphenol in its own right — and it gives the capsule its natural yellow colour.
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⚖️Honest by design. Using a second active instead of filler keeps the capsule consistent and meaningful — every component is doing something.
What “HPLC tested” means
HPLC — High-Performance Liquid Chromatography — is the lab method that separates a sample and measures exactly how much of each compound is present. It's how you prove trans-purity instead of just printing a number.
We HPLC-test both actives for purity — so the dose on the label is the dose doing the work, every time.
Two actives, both verified — every milligram is accounted for, nothing inflating the headline number.
Resveratrol & quercetin, answered
Read the label, not the headline.
Check for trans-resveratrol, a stated purity, and what makes up the rest of the capsule. That's all this page is really about — helping you understand what you're taking.
This content is for education only and is not medical advice or an authorised health claim. References to resveratrol and quercetin describe compounds studied in published research; they do not imply any specific health benefit. The 150 mg/day figure refers to the maximum permitted level for adults for trans-resveratrol food supplements (capsule/tablet form). Always consult a qualified healthcare provider before changing your supplement regimen.