Updated November 2026. Sources and the Verve Ca-AKG label checked on 5 November 2026. Verve makes a Ca-AKG supplement, covered near the end. No authorised health claim exists in Great Britain for alpha-ketoglutarate, and we make none.
Ca-AKG is calcium alpha-ketoglutarate: the calcium salt of alpha-ketoglutarate (AKG), a small organic acid that cells make as an intermediate in the citric acid cycle. On a UK label, 1000mg of Ca-AKG is not 1000mg of AKG. By our calculation from the formula, 1000mg of Ca-AKG is about 782mg of alpha-ketoglutarate and 218mg of calcium, which is 27% of the 800mg calcium NRV. There are no authorised health claims for AKG in Great Britain, so this guide explains the compound and the label, not what it does. The calcium counts towards your daily total.
The short answer
- Ca-AKG is calcium plus AKG. Formula CaC5H4O5, molar mass 184.16.
- 1000mg of Ca-AKG is about 782mg of AKG and 218mg of calcium. Our calculation; brands that declare calcium show 205mg to 220mg.
- Typical UK label dose: 400mg to 550mg per capsule, two capsules a day, most often 1,000mg, in 60-capsule packs.
- No authorised GB health claims for AKG. Calcium has them, if the product gives at least 15% of its NRV.
- From Verve: Verve Ca-AKG 1000mg, 1000mg of calcium alpha-ketoglutarate per two capsules, one ingredient, every batch independently lab-tested for purity, with the certificate for your batch on request, and made in the UK.
- Check with a doctor first if you are pregnant, breastfeeding, taking medication or have a medical condition. Not suitable for children.
What alpha-ketoglutarate is
Alpha-ketoglutarate is an intermediate of the citric acid cycle, the set of reactions cells use to oxidise fuel. The textbook account (Berg, Tymoczko and Stryer, Biochemistry, 5th edition, section 17.1) is this: isocitrate is oxidised and decarboxylated by the enzyme isocitrate dehydrogenase, losing carbon dioxide to form alpha-ketoglutarate, which is then oxidised and decarboxylated again to form succinyl CoA. The cycle is also called the TCA or Krebs cycle.
Its chemical names are alpha-ketoglutaric acid, 2-oxoglutaric acid and 2-oxopentanedioic acid, shortened to AKG or α-KG. The acid is C5H6O5, molar mass 146.10 (CAS 328-50-7). Your cells make it. It is not a vitamin or a mineral, it has no NHS daily amount and no NRV, and the food database FooDB lists it only as detected, not quantified, in foods such as beetroot.
What the calcium salt is, and why labels say Ca-AKG
For a capsule, the acid is sold as a salt, and supplements use the calcium salt: calcium 2-oxoglutarate (CAS 71686-01-6). One calcium ion pairs with one alpha-ketoglutarate ion to give CaC5H4O5, molar mass 184.16. Suppliers list the monohydrate (one water molecule per unit of salt) under the same CAS number, so "Ca-AKG" can be either form.
The label says "Ca-AKG" or "calcium alpha-ketoglutarate" because that is the ingredient as sold, and the milligram figure is the weight of the salt, calcium included. A good label adds an "of which" line for the alpha-ketoglutarate and a calcium line with its %NRV.
Do not confuse Ca-AKG with AAKG. Arginine alpha-ketoglutarate is a salt of the amino acid arginine and alpha-ketoglutaric acid, sold as a pre-workout ingredient.
How much of 1000mg Ca-AKG is AKG, and how much is calcium
This is our calculation from the formula, using standard atomic weights. Calcium is 21.8% of the anhydrous salt by weight and the alpha-ketoglutarate ion 78.2%.
| Per 1000mg of Ca-AKG | Anhydrous salt | Monohydrate |
|---|---|---|
| Alpha-ketoglutarate (as the ion) | 782mg | 713mg |
| Alpha-ketoglutarate (as the free acid) | 793mg | 723mg |
| Calcium | 218mg (27% NRV) | 198mg (25% NRV) |
Two UK brands declare the calcium: one gives 220mg per 1,100mg of Ca-AKG, the other 205mg (26% NRV) plus 753mg of alpha-ketoglutaric acid per 1,000mg. Both sit a little under the anhydrous figures, which points to some water in the material or a purity a little under 100%.
The NHS says adults aged 19 to 64 need 700mg of calcium a day and that 1,500mg or less a day from supplements is unlikely to cause harm; more than that could lead to stomach pain and diarrhoea. Add the Ca-AKG calcium to any calcium tablet or multivitamin you take. The 800mg figure is the NRV, explained in our guide to what NRV means on a label.
Calcium: the one part of the label with authorised claims
There are eight authorised GB health claims for calcium in retained Regulation (EU) No 432/2012. Two of them, word for word: "Calcium is needed for the maintenance of normal bones" and "Calcium contributes to normal muscle function". Each may be used only for a food that is at least a source of calcium: 15% of the NRV, so 120mg in a supplement's recommended daily portion.
Verve's Ca-AKG label does not declare calcium, so no calcium claim is made for it. By our calculation two capsules hold about 218mg of calcium, but that is our arithmetic, not a tested label value. And the claims are about calcium, not alpha-ketoglutarate, which has none.
Typical label doses in the UK
UK Ca-AKG capsules run from 400mg to 550mg per capsule. The daily serving is two capsules, giving 800mg to 1,100mg, with 1,000mg the most common figure, in 60-capsule packs. Directions are two capsules a day with water, and some labels say morning. When you compare labels, read three lines: the Ca-AKG weight per serving, whether calcium and its %NRV are declared, and whether there is an "of which alpha-ketoglutaric acid" line. Only one of the UK labels we read gave all three.
Purity and certificates of analysis
A certificate of analysis (CoA) is the laboratory report for a batch. For Ca-AKG it should show the batch number, an identification test, an assay figure (the percentage of the powder that is Ca-AKG), the calcium content, water content or loss on drying, heavy metals (lead, arsenic, cadmium and mercury) and microbiological results (total plate count, yeasts and moulds, E. coli and Salmonella).
Match the batch number to your pot. The assay tells you how much of the stated 1000mg is Ca-AKG: a 98% assay means about 980mg. The water figure tells you whether you have the anhydrous salt or the hydrate. A purity percentage on a web page usually describes the raw material, not the finished capsule. Of the UK pages we read, one states 98% purity and one links to a certificate; Verve tests every batch for purity; the certificate of analysis, with the figure, is available on request from hello@vavaverve.com.
Who should check with a doctor first
The Verve label wording is the sensible rule for any Ca-AKG product: 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 Ca-AKG do?
No health claim for alpha-ketoglutarate or Ca-AKG is authorised in Great Britain, so this guide describes the compound and the label, not effects, and Verve makes no claim for it. What can be said is the chemistry: alpha-ketoglutarate is an intermediate in the citric acid cycle, and the calcium in Ca-AKG is ordinary dietary calcium. Anything beyond that on a product page is the brand's view.
Verve Ca-AKG: what the label says
Verve Ca-AKG is calcium alpha-ketoglutarate, 1000mg per two capsules, 500mg per capsule, 60 capsules to a pot. One ingredient plus a plant cellulose shell. The label table reads:
| Ingredient (as sold) | Per serving (2 capsules) | NRV% |
|---|---|---|
| Calcium Alpha-Ketoglutarate (Ca-AKG) | 1000mg | Not established |
By our calculation that serving gives about 218mg of calcium (27% NRV). The label does not declare calcium separately. Every batch is independently lab-tested for purity; the certificate of analysis for your batch is available on request from hello@vavaverve.com. How to take it, from the label: two capsules, once a day, with water, in the morning, alongside NMN if you take it. Do not exceed the recommended daily dose. It contributes calcium, so factor it in if you already supplement calcium. The page lists it as vegan. Full details are on the Verve Ca-AKG 1000mg page. Our Ca-AKG label comparison sets UK labels side by side, and the longevity stack guide covers how it sits with NMN and TMG.
Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. Do not exceed the recommended daily intake.
Ca-AKG: your questions
Is Ca-AKG the same as AKG?
No. AKG is alpha-ketoglutarate, the acid or its ion. Ca-AKG is its calcium salt, about 22% calcium by weight, so 1000mg of Ca-AKG gives about 782mg of alpha-ketoglutarate by our calculation.
How much calcium is in Ca-AKG?
About 218mg per 1000mg for the anhydrous salt, 27% of the 800mg NRV. UK brands that declare it show 205mg to 220mg per serving. Add it to any other calcium supplement you take.
Is Ca-AKG the same as AAKG?
No. AAKG is arginine alpha-ketoglutarate, a salt of the amino acid arginine and alpha-ketoglutaric acid, sold as a pre-workout ingredient. Ca-AKG is the calcium salt.
How much Ca-AKG is a normal dose?
UK labels give 800mg to 1,100mg a day as two capsules of 400mg to 550mg, and 1,000mg is the most common figure. Verve's is 1000mg as two 500mg capsules.
How we checked
Citric acid cycle: Berg, Tymoczko and Stryer, Biochemistry, 5th edition (2002), section 17.1, NCBI Bookshelf. Alpha-ketoglutaric acid and its food occurrence: Sigma-Aldrich (K1750) and FooDB (FDB003361). Calcium 2-oxoglutarate and its monohydrate: ChemicalBook (CAS 71686-01-6). AAKG: Wikipedia. Calcium: nhs.uk, vitamins and minerals, calcium (last reviewed August 2020). NRV and the 15% rule: Annex XIII of retained Regulation (EU) No 1169/2011; calcium claims: the Annexes to retained Regulation (EU) No 432/2012 and Regulation (EC) No 1924/2006; per daily portion: Article 8 of Directive 2002/46/EC, all on legislation.gov.uk. UK label doses: Time Health and Naturecan UK product pages, and the Healf listings for Youth and Earth, DoNotAge and Longevity Box. Verve figures: the Ca-AKG label table on vavaverve.com. All checked on 5 November 2026. Verve makes Ca-AKG.
