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Calcium Alpha-Ketoglutarate (Ca-AKG)
Bottom line
In our scoring, Calcium Alpha-Ketoglutarate (Ca-AKG) rates weak evidence: the human evidence is thin for associated with lower biological-age markers. Our top-scored product is Ca AKG 1500mg (84/100), about $0.42 a day at a clinical dose of ~1. Bottom line: treat any benefit as unproven. This is our opinion, not medical advice; talk to your clinician before starting.
Calcium alpha-ketoglutarate (Ca-AKG) is one of the marquee names in the longevity-supplement boom, sold almost entirely on the promise of lowering your "biological age." The honest verdict: genuinely interesting biology, striking mouse data, and exactly one small human study that is too weak to prove anything on its own.
- Evidence
- Weak Evidence
- Category
- Energy & Performance
- Best form
- calcium alpha-ketoglutarate (the salt used in the research)
- Effective dose
- ~1,000 mg/day of the calcium salt, often as a sustained-release tablet (the dose used in the human study and the ongoing RCT)
- Lab tested
- 3 of 6 products
- Category
- Energy & Performance
- Best form
- calcium alpha-ketoglutarate (the salt used in the research)
- Effective dose
- ~1,000 mg/day of the calcium salt, often as a sustained-release tablet (the dose used in the human study and the ongoing RCT)
- Lab tested
- 3 of 6 products
Key takeaways
- →Interesting biology and striking mouse data (extended lifespan, less late-life frailty), but only one small, uncontrolled human study - which cannot prove the 'biological age' claim.
- →The definitive placebo-controlled human trial (ABLE) is running but unpublished. Treat Ca-AKG as an early-science bet, not a proven anti-aging tool.
- →Buy the calcium salt at ~1,000 mg/day - not plain 'AKG' acid or 'AAKG' (arginine AKG), which are different molecules. Toniiq (~$0.42/day, third-party tested) is our Top Pick; Rejuvant is the pricey clinical-pedigree option.
- →Ignore any 'lowers your biological age by X years' marketing - that rests on one retrospective, industry-linked study.
What Is Calcium Alpha-Ketoglutarate (Ca-AKG)?
Calcium alpha-ketoglutarate (Ca-AKG) is one of the marquee names in the longevity-supplement boom, sold almost entirely on the promise of lowering your "biological age." The honest verdict: genuinely interesting biology, striking mouse data, and exactly one small human study that is too weak to prove anything on its own. The definitive trial is running but not yet published. This is a reasonable early-science bet for the longevity-curious, not an established anti-aging tool - and the marketing claims run well ahead of the evidence.
Alpha-ketoglutarate is a normal metabolite in your cells' energy cycle, and its levels fall sharply with age. The mouse data is real and notable: in a 2020 study (Asadi Shahmirzadi), Ca-AKG started in late life extended median lifespan and, importantly, compressed the frail, sick period at the end of life, with the effect strongest in females. That "compress the bad years" finding is what made the longevity world pay attention.
The human evidence is where honesty matters most. There is one study (Demidenko 2021), and it reported an eye-catching roughly 8-year reduction in a DNA-methylation "biological age" test after about seven months on Rejuvant. But it was retrospective, had no placebo or control group, included only 42 self-selected users, and came from the company's own research group. A design like that can generate a hypothesis; it cannot prove that Ca-AKG lowered anyone's biological age. The proper test - the placebo-controlled ABLE trial - is underway (recruitment reported by Lim in 2025) but has not published results. So "reduces your biological age" is a claim the data does not yet support.
A buyer's note that trips a lot of people up: make sure you are actually buying the calcium salt. Plain "AKG" (alpha-ketoglutaric acid) and "AAKG" (arginine AKG, a pre-workout ingredient) are different molecules that rank for the same searches, and none of the longevity research used them. Rejuvant is the exact formulation from the human study and carries that pedigree at a steep price; generic Ca-AKG from brands that publish testing delivers the same molecule at the studied ~1,000 mg dose for a fraction of the cost.
Does It Work? The Evidence
How A-F grades workCalcium Alpha-Ketoglutarate (Ca-AKG) earns a Weak Evidence rating - human evidence is thin across its claimed uses, the best-supported being associated with lower biological-age markers and extends lifespan and compresses late-life frailty (in mice) (grade C). Each claim is graded individually below.
Associated with lower biological-age markers
Demidenko et al. 2021 (Aging): a retrospective, uncontrolled study of 42 Rejuvant users reported ~8-year lower DNA-methylation age after ~7 months - hypothesis-generating, not causal (no placebo/control)
Extends lifespan and compresses late-life frailty (in mice)
Asadi Shahmirzadi et al. 2020 (Cell Metabolism): late-onset Ca-AKG increased median lifespan and reduced frailty in mice, strongest in females; linked to reduced systemic inflammation
Supports healthy aging / cellular energy metabolism
Mechanistic rationale: AKG is a central metabolite in the citric-acid cycle whose levels decline markedly with age; supplementation aims to restore it
Proven to slow human aging in a controlled trial
The placebo-controlled ABLE RCT (1 g/day sustained-release Ca-AKG) is underway - recruitment reported by Lim et al. 2025 - but efficacy results are not yet published
| Grade | Claimed Benefit | Key Studies | Our Verdict |
|---|---|---|---|
| C | Associated with lower biological-age markers | Demidenko et al. 2021 (Aging): a retrospective, uncontrolled study of 42 Rejuvant users reported ~8-year lower DNA-methylation age after ~7 months - hypothesis-generating, not causal (no placebo/control) | Early Signal |
| C | Extends lifespan and compresses late-life frailty (in mice) | Asadi Shahmirzadi et al. 2020 (Cell Metabolism): late-onset Ca-AKG increased median lifespan and reduced frailty in mice, strongest in females; linked to reduced systemic inflammation | Early Signal |
| C | Supports healthy aging / cellular energy metabolism | Mechanistic rationale: AKG is a central metabolite in the citric-acid cycle whose levels decline markedly with age; supplementation aims to restore it | Early Signal |
| F | Proven to slow human aging in a controlled trial | The placebo-controlled ABLE RCT (1 g/day sustained-release Ca-AKG) is underway - recruitment reported by Lim et al. 2025 - but efficacy results are not yet published | Not There Yet |
How to Choose: Forms, Doses & What Matters
Clinical dose: ~1,000 mg/day of the calcium salt, often as a sustained-release tablet (the dose used in the human study and the ongoing RCT)
Best forms: calcium alpha-ketoglutarate (the salt used in the research), sustained-release for the ~1,000 mg dose, NOT plain 'AKG' acid or AAKG (arginine AKG) - different molecules
Take about 1,000 mg per day, ideally as a sustained-release form (the studied products use controlled release). It supplies a modest amount of elemental calcium (roughly 200 mg per gram of Ca-AKG), which counts toward your daily calcium. There is no established need to cycle it. Because the effects being studied are long-term, judge it over months, not weeks - and recognize that any 'biological age' benefit is unproven, so track how you feel rather than expecting a measurable age reversal.
Who Should Take Calcium Alpha-Ketoglutarate (Ca-AKG)?
This suits people who follow longevity science, understand they are betting on strong animal data plus one weak human study rather than proven results, and want a well-tolerated, moderately-priced experiment. If you are drawn to the biological-age idea, Ca-AKG is one of the more plausible options - just go in with calibrated expectations and buy the calcium salt at the studied dose.
Who Should Avoid It?
Not for everyone
Side Effects & Safety
Product Scores
6 products scored on dosing accuracy, third-party testing, cost per effective dose, and label transparency.
The Scorecard: 6 Products Compared
Ca AKG 1500mg
Toniiq
$24.97 ÷ 59 days at ~1009mg/day (0.7 servings × 1500mg)
The sensible default: the exact molecule the research used, third-party tested, at a small fraction of Rejuvant's price. In our view the value more than offsets the lack of a sustained-release delivery.
Prices checked 2026-07-05. Cost shown is per clinically effective daily dose, not per pill.
Ca AKG 1000mg
PartiQlar
$34.95 ÷ 30 days at 1000mg/day (1 serving × 1000mg)
A clean, tested 1,000 mg option, though Toniiq delivers the same molecule for less.
Prices checked 2026-07-05. Cost shown is per clinically effective daily dose, not per pill.
Ca-AKG Time-Release
LongJuvity
$29.95 ÷ 30 days at 1000mg/day (1 serving × 1000mg)
A middle-ground pick: the time-release delivery is a genuine nod to the studied formulation, at a more reasonable price than Rejuvant.
Prices checked 2026-07-05. Cost shown is per clinically effective daily dose, not per pill.
Calcium AKG Powder
Maxx Herb
$29.95 ÷ 100 days at ~1007mg/day (0.7 servings × 1500mg)
The cheapest way to get the molecule, but with no testing documentation and imprecise powder dosing. We keep it out of the auto Best Value slot in favor of a tested option.
Prices checked 2026-07-05. Cost shown is per clinically effective daily dose, not per pill.
Calcium AKG
ProHealth Longevity
$39.95 ÷ 30 days at 1000mg/day (1 serving × 1000mg)
A reasonable option from an established longevity house, but priced above the value picks for the same molecule and dose.
Prices checked 2026-07-05. Cost shown is per clinically effective daily dose, not per pill.
Rejuvant AKG Longevity (Original)
Rejuvant
$89.00 ÷ 60 days at 1000mg/day (1 serving × 1000mg)
The clinical-pedigree pick, and the reason the (thin) human data exists. But at ~$1.48/day for a preliminary-evidence supplement, the premium over a tested generic is hard to justify for most people.
Prices checked 2026-07-05. Cost shown is per clinically effective daily dose, not per pill.
Full Comparison
| Category | Ca AKG 1500mg Toniiq | Ca AKG 1000mg PartiQlar | Ca-AKG Time-Release LongJuvity | Calcium AKG Powder Maxx Herb | Calcium AKG ProHealth Longevity | Rejuvant AKG Longevity (Original) Rejuvant |
|---|---|---|---|---|---|---|
| Brand Score | 84/100Winner | 70/100 | 69/100 | 66/100 | 66/100 | 63/100 |
| Dosing & Form | 24/25Winner | 22/25 | 22/25 | 20/25 | 22/25 | 23/25 |
| Purity | 16/25Winner | 15/25 | 14/25 | 11/25 | 14/25 | 15/25 |
| Value | 23/25Winner | 13/25 | 15/25 | 22/25 | 11/25 | 8/25 |
| Transparency | 21/25Winner | 20/25 | 18/25 | 13/25 | 19/25 | 17/25 |
| Cost/Day | $0.42 | $1.17 | $1.00 | $0.30Winner | $1.33 | $1.48 |
| Dose/Serving | 1500mg | 1000mg | 1000mg | 1500mg | 1000mg | 1000mg |
| Form | Veggie capsule (calcium alpha-ketoglutarate) | Capsule (calcium alpha-ketoglutarate) | Time-release capsule (calcium AKG + piperine) | Powder (calcium alpha-ketoglutarate) | Capsule (calcium alpha-ketoglutarate) | Sustained-release tablet (calcium alpha-ketoglutarate) |
| Third-Party Tested | ✓ Yes | ✓ Yes | ✓ Yes | No | No | No |
| Proprietary Blend | No | No | No | No | No | No |
Frequently Asked Questions
Does calcium AKG actually lower your biological age?
There is no good evidence that it does. The claim comes from a single 2021 study of 42 Rejuvant users that reported about an 8-year drop in a DNA-methylation age test - but it was retrospective, had no placebo or control group, and came from the company's own researchers, so it cannot prove cause and effect. The mouse data (longer lifespan, less late-life frailty) is more solid but is still mice. The proper placebo-controlled human trial is underway and unpublished. Treat 'lowers your biological age' as an unproven marketing claim.
What is the difference between Ca-AKG, AKG, and AAKG?
They are different molecules that unfortunately rank for the same searches. Calcium alpha-ketoglutarate (Ca-AKG) is the calcium salt used in all the longevity research. Plain 'AKG' (alpha-ketoglutaric acid) is the unbuffered acid - a different, cheaper product not used in the aging studies. 'AAKG' is arginine alpha-ketoglutarate, a pre-workout 'pump' ingredient entirely unrelated to longevity. If you want the researched compound, make sure the label says calcium alpha-ketoglutarate.
Is Rejuvant worth the premium over generic Ca-AKG?
Rejuvant is the exact sustained-release formulation used in the one human study, which is its real selling point, and it is priced accordingly - roughly $1.50 a day. Generic Ca-AKG from brands that publish third-party testing delivers the same molecule at the studied ~1,000 mg dose for a fraction of that. In our view, since the human evidence is preliminary either way, most people are better served by a tested generic at the studied dose than by paying a large premium for the pedigree. The sex-specific 'men's/women's' Rejuvant formulas rest on a mouse-data extrapolation, not human proof.
How much calcium AKG should I take?
The human study and the ongoing trial use about 1,000 mg per day, ideally as a sustained-release form. Some products deliver 1,500 mg. There is no evidence that more is better, so around 1 gram a day at the studied dose is the sensible target. Note it also supplies roughly 200 mg of elemental calcium per gram, which counts toward your daily calcium intake.
Is calcium AKG safe?
It appears well tolerated in the available studies, with no significant adverse-event signal and only occasional mild digestive upset reported. The main caveat is that robust long-term human safety data is still limited, since this is a relatively new longevity supplement. It also adds a small amount of calcium, worth keeping in mind if you already supplement calcium. Pregnant and breastfeeding people should avoid it for lack of data.
Related Reading
Sources
- Asadi Shahmirzadi A, et al. Alpha-Ketoglutarate, an Endogenous Metabolite, Extends Lifespan and Compresses Morbidity in Aging Mice. Cell Metab. 2020;32(3):447-456.e6.
- Demidenko O, et al. Rejuvant, a potential life-extending compound formulation with alpha-ketoglutarate and vitamins, conferred an average 8 year reduction in biological aging, after an average of 7 months of use, in the TruAge DNA methylation test. Aging (Albany NY). 2021;13(22):24485-24499.
- Lim ZM, et al. Recruitment evaluation of a gerotherapeutic randomized controlled trial testing alpha-ketoglutarate (ABLE study). Exp Gerontol. 2025.
Scores and tiers are our independent opinion, formed by applying a published rubric to label data, third-party certifications, and the research record. They are not statements of objective fact about a product and not a lab test. Where we report a brand-specific fact, it comes from a cited source or a public certification; where verification is missing, we say so rather than assume a result.
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare professional before starting any supplement regimen.