Updated November 2026. Chemistry, food figures and UK label wording checked on 5 and 6 November 2026. Verve makes Resveratrol Balance 440mg Capsules, described near the end.
Resveratrol is a plant compound: a stilbene with the formula C14H12O3. It comes in two shapes, trans and cis, so many labels say "trans-resveratrol" to show which form the milligrams refer to. It occurs in grape skins, red wine, peanuts and some berries, at about a milligram or less a portion, and in the root of Japanese knotweed, the plant most supplement resveratrol is extracted from. UK labels state it as trans-resveratrol in milligrams, as a knotweed extract with a percentage, or as "resveratrol" alone, mostly at 200mg to 1,000mg a day. There are no authorised health claims for resveratrol in Great Britain, so this guide describes the compound and the label, not effects. Check with your doctor first if you are pregnant, breastfeeding, taking medication or have a medical condition. Not suitable for children.
The short answer
- Resveratrol is a stilbene, C14H12O3, molecular weight 228.24, made by plants in response to stress, injury, fungal infection and UV light.
- Trans and cis are two shapes of one molecule. Extracts are standardised to trans-resveratrol. Light turns trans into cis.
- Most supplement resveratrol comes from Japanese knotweed root (Polygonum cuspidatum, also named Reynoutria japonica). Some is made by yeast fermentation.
- Do the sum on an extract. 500mg of a 50% extract is 250mg of trans-resveratrol.
- No authorised GB health claims exist for resveratrol. A label can tell you dose, form, source and purity, nothing more.
- From Verve: Verve Resveratrol Balance 440mg, 440mg of resveratrol per daily serving, every batch independently lab-tested for purity, with the certificate for your batch on request, and made in the UK.
What resveratrol is
The NIST Chemistry WebBook lists resveratrol (CAS 501-36-0) as C14H12O3, molecular weight 228.24. Its other name, 3,4',5-trihydroxystilbene, describes the shape: two benzene rings joined by a carbon-carbon double bond, carrying three hydroxyl (OH) groups. That frame is a stilbene, and the Linus Pauling Institute classes resveratrol as a polyphenol in the stilbene group. The Institute says plants make it in response to stress, injury, fungal infection or UV radiation. Plants also hold it bound to a sugar, as piceid (also called polydatin), the main form in grapes.
Trans and cis: why labels say "trans-resveratrol"
The double bond fixes the two rings in one of two positions. In trans-resveratrol, written (E), they sit on opposite sides of the bond. In cis-resveratrol, written (Z), they sit on the same side. Same atoms, same formula, different shape. The NIST entry is the trans form.
Supplement extracts are usually standardised to trans-resveratrol. A 2012 study of 14 retail products (Rossi and colleagues) lists extracts standardised to 99% and to 50% trans-resveratrol. A label that says only "resveratrol" gives the amount but not the form. Cis-resveratrol is not rare: the Linus Pauling Institute says many wines contain significant amounts.
Light turns trans into cis
A 2025 review in Molecules (Jaa and colleagues) says UV radiation converts trans-resveratrol to cis. In an alcohol solution, over 90% converted within 80 minutes under 366nm UV light, and the review puts the half-life in sunlight at under 10 minutes. That is resveratrol dissolved in liquid, not powder in a capsule, but it explains the storage lines. One supplier's specification for a 98% knotweed extract says to keep it in tight, light-resistant containers, away from sunlight, moisture and heat. Kiki Health, Longevity Box and Youth & Earth say to store it away from sunlight or in the dark. Several UK pages say nothing.
Where resveratrol occurs
The Linus Pauling Institute (Oregon State University) lists grapes, wine, grape juice, peanuts, cocoa and Vaccinium berries (blueberries, bilberries, cranberries) as sources. In grapes it is found only in the skins. Its figures are small and vary a lot.
| Food | Linus Pauling Institute figure | Our conversion |
|---|---|---|
| Red grapes | 0.24 to 1.25mg per cup (160g) | 0.15 to 0.78mg per 100g |
| Peanuts, boiled | 0.32 to 1.28mg per cup (180g) | 0.18 to 0.71mg per 100g |
| Peanuts, raw | 0.01 to 0.26mg per cup (146g) | 0.01 to 0.18mg per 100g |
| Peanut butter | 0.04 to 0.13mg per cup (258g) | 0.02 to 0.05mg per 100g |
| Red wine (trans-resveratrol) | 1.9mg per litre, global mean | About 0.3mg in a 175ml glass |
No berry figures are given, so we have added none. For scale, 440mg is the resveratrol in over 50kg of red grapes at the top of that range, on our arithmetic.
For supplements, the plant that matters is Japanese knotweed. A 2022 review in Frontiers in Pharmacology (Liu and colleagues) names it Reynoutria japonica Houtt., also known as Polygonum cuspidatum Sieb. et Zucc. and Fallopia japonica. Its stilbenes, resveratrol and polydatin among them, sit mostly in the roots and rhizomes, with anthraquinones, a different group of compounds that includes emodin. Labels use all three plant names.
How supplement resveratrol is made
Extracted from knotweed. The Linus Pauling Institute says most US resveratrol supplements contain Polygonum cuspidatum root extract. UK labels follow the pattern: Kiki Health, Time Health, Welzo, Youth & Earth, Peak Supps and Simply Supplements all name knotweed. Grape and red wine extracts are also sold.
Made by fermentation. Yeast can be engineered to make resveratrol. A 2022 review (Feng and colleagues) says Saccharomyces cerevisiae, baker's yeast, is the host most often used. Sunday Natural's UK site says its trans-resveratrol is "produced by fermentation" with yeast, at over 98%.
What "98% trans-resveratrol" means
The percentage is the share of the ingredient's weight that is trans-resveratrol, measured in a laboratory, usually by HPLC. At 98%, nearly all of it is. At 50%, half is, and the rest is other root material. Multiply the extract weight by the percentage to get the active amount. This is our arithmetic unless the label states it.
| On the label | Trans-resveratrol (our arithmetic) |
|---|---|
| 500mg of a 50% extract | 250mg |
| 250mg knotweed root at 50%, plus 40mg grape skin at 5% (Time Health, per capsule) | 125mg plus 2mg |
| 400mg extract at 98% (Kiki Health, per capsule) | 392mg, as the label also states |
| 1,000mg extract at 98% (Welzo, per daily serving) | 980mg; the page gives no mg figure |
The rest of a lower-grade extract matters too. One supplier's specification for a 50% knotweed extract (Total Ingredients) lists emodin at not less than 2%, as a brown granule. Its 98% grade is an off-white powder with no emodin line. An extract weight with no percentage cannot be turned into a resveratrol figure.
Dose per capsule and per serving
Read milligrams per capsule, capsules per serving and servings per pack. On the brands' own UK pages in November 2026:
- One 500mg capsule a day: DoNotAge and Naturecan (trans-resveratrol), Sunday Natural (from fermentation).
- 1,000mg as two capsules: Charava (99% trans-resveratrol) and Longevity Box.
- One 392mg capsule: Kiki Health, from 400mg of 98% extract.
- Two capsules of about 125mg: Time Health, morning and evening.
- 200mg across two capsules, in a blend: Youth & Earth, with quercetin and curcumin.
- 440mg across four capsules: Verve, two morning and two evening, 110mg a capsule on our arithmetic.
So "500mg" can be a whole day or half of one. These are label statements, not recommendations. Resveratrol has no NRV, so the NRV column shows a dash (see what NRV means). The labels are compared side by side in best resveratrol supplement UK.
Purity and certificates of analysis
A certificate of analysis (CoA) is the laboratory report for one batch. Labels and contents do not always match. In Rossi and colleagues' 2012 study of 14 retail products, five held 95% to 105% of the labelled amount, four were slightly outside that range, three held 8% to 64%, and two were below the detection limit. On a certificate, check:
- Batch number against your pack, and whether it covers the finished capsules or only the raw ingredient.
- Identity and assay: the compound named (trans-resveratrol, not just resveratrol), the percentage and the method, usually HPLC.
- Heavy metals: lead, arsenic, cadmium and mercury, each against a limit.
- Microbiology: total plate count, yeast and mould, E. coli and Salmonella.
- Emodin, for a knotweed extract below 98%.
Longevity Box, Naturecan and Youth & Earth link a certificate on the page. A purity figure with no certificate behind it is the brand's statement, not a result.
Who should check with a doctor first
Verve's product page uses this wording: consult your doctor before use if you are pregnant, breastfeeding, taking medication or have a medical condition. Not suitable for children. Keep out of reach of children. Do not exceed the recommended daily dose.
What does resveratrol do?
There are no authorised health claims for resveratrol on the Great Britain nutrition and health claims register. No UK brand, Verve included, may tell you what it does for your health, and this guide does not. Anything more on a product page is the brand's wording, not an authorised claim.
Verve Resveratrol Balance 440mg Capsules
Verve's label table is one line: resveratrol, 440mg per serving, NRV not established. The label does not state trans- or cis-, and it does not name a source plant or method. If the form or source matters to you, ask Verve before you buy. Take two capsules in the morning and two in the evening, with water: 440mg a day in total. Verve lists it as gluten free, dairy free, soy free, vegetarian and vegan. Every batch is independently lab-tested for purity. The certificate of analysis for your batch is available on request from hello@vavaverve.com. The cautions above apply, and the page has no storage line. The label is on the Resveratrol Balance 440mg Capsules page.
featured in this article
440mg resveratrol per serving
From €34,81/month
Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. Do not exceed the recommended daily dose.
Resveratrol: your questions
Is resveratrol the same as trans-resveratrol?
Trans-resveratrol is one of resveratrol's two forms; the other is cis. They share the formula C14H12O3 but differ in shape. "Trans-resveratrol 500mg" gives the form and the amount. "Resveratrol 500mg" gives the amount only.
Which foods contain resveratrol?
Grape skins, red wine, peanuts, cocoa and berries such as blueberries and cranberries, in small amounts. On Linus Pauling Institute figures, red grapes hold 0.15 to 0.78mg per 100g and red wine about 1.9mg per litre on average.
What does 98% trans-resveratrol mean?
That 98% of the ingredient's weight is trans-resveratrol, by laboratory test. 400mg of a 98% extract is 392mg. A 50% extract is half trans-resveratrol, so 500mg of it is 250mg.
What does resveratrol do?
No health claim for resveratrol is authorised in Great Britain, so no UK brand may say what it does, and this guide does not. It is a stilbene that plants make in response to stress, injury, fungal infection and UV light.
How we checked
Chemistry: NIST Chemistry WebBook, resveratrol (CAS 501-36-0). Stilbene group, plant role, food figures and supplement sources: Linus Pauling Institute Micronutrient Information Center, "Resveratrol" (Oregon State University, updated 2015); the conversions are ours. Light: Jaa A and colleagues, Molecules 2025;30(3):536. Knotweed: Liu S and colleagues, Frontiers in Pharmacology 2022;13:863707. Fermentation: Feng C and colleagues, Frontiers in Bioengineering and Biotechnology 2022;10:833920. Label accuracy and standardisation: Rossi D and colleagues, Molecules 2012;17(10):12393-12405. Specifications: total-ingredients.com. UK labels: the brands' own websites, read on 5 November 2026 (Sunday Natural on 6 November). Verve figures: its product page and label table. We found no NHS page on resveratrol. No prices are compared. Other sources read on 6 November 2026. Verve makes Resveratrol Balance 440mg Capsules.
