Calcium Alpha-Ketoglutarate
Other ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Calcium alpha-ketoglutarate is a calcium salt of alpha-ketoglutarate (AKG), a central intermediate of the Krebs (TCA) cycle that links carbon, nitrogen, and energy metabolism. It is marketed (notably as Rejuvant) as a longevity supplement intended to support healthy aging via metabolic and epigenetic pathways. Interest is driven by mouse studies showing extended healthspan and a small open-label human trial reporting reductions in DNA-methylation biological age, though rigorous controlled human evidence remains preliminary.
Exploratory record, not a reviewed medical publication.
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This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
Calcium Alpha-Ketoglutarate is an other most often used for may support healthy aging and reduce biological (epigenetic) age markers, provides bioavailable calcium for bone and muscle support, supports cellular energy metabolism as a tca-cycle intermediate. NutriStack rates the overall evidence as emerging. A typical adult dose is 1000-3000 mg per day of calcium alpha-ketoglutarate, often split into two doses (the Rejuvant protocol uses about 1000 mg twice daily), commonly taken as calcium alpha-ketoglutarate powder in capsules; sustained or divided dosing is commonly used. This profile indexes 8 sources.
- May support healthy aging and reduce biological (epigenetic) age markers7,3
- Provides bioavailable calcium for bone and muscle support1,5
- Supports cellular energy metabolism as a TCA-cycle intermediate3,4
- May reduce markers of systemic inflammation7
- Investigated for support of muscle and physical function in aging7
The bottom line
Evidence rating emerging. Most-documented uses: may support healthy aging and reduce biological (epigenetic) age markers, provides bioavailable calcium for bone and muscle support, supports cellular energy metabolism as a tca-cycle intermediate. 8 sources indexed (2007–2021), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Alpha-ketoglutarate sits at a metabolic crossroads in the TCA cycle, where it is generated from isocitrate and converted to succinyl-CoA, feeding cellular ATP production and amino acid metabolism via transamination reactions. Beyond bioenergetics, AKG is an obligate co-substrate for the 2-oxoglutarate-dependent dioxygenase family of enzymes, which includes prolyl hydroxylases (regulating HIF and collagen), TET DNA demethylases, and Jumonji-domain histone demethylases. Through these enzymes AKG influences DNA and histone methylation states, providing a proposed link to epigenetic 'reprogramming' of biological age. Proposed downstream effects include modulation of mTOR signaling, reduced systemic inflammation, support of collagen and bone matrix synthesis, and improved mitochondrial efficiency, with the bound calcium also contributing mineral intake.2,1
Dosing & protocol.
Water-soluble; taking with food can reduce gastrointestinal discomfort and aid calcium absorption. Separate from supplements or medications whose absorption is impaired by calcium (for example certain antibiotics, levothyroxine, and iron) by several hours. Calcium intake should be split across the day for better uptake.1,2
What it actually costs.
Real-world pricing across three quality tiers. Assumes Calcium alpha-ketoglutarate capsules.
Effective dose assumed at ~1,000 mg/day. Budget tier reflects generic bulk Ca-AKG powder or commodity capsules; mid tier reflects standard branded capsule products; premium reflects branded longevity products such as Rejuvant, which carry a substantial markup over the cost of the underlying ingredient. Prices are approximate US retail and vary with formulation and pack size. Updated 2026-06-04.
Full safety detail.
Side effects
- Generally well tolerated in short-term studies
- Mild gastrointestinal upset, nausea, or bloating
- Possible constipation from the calcium content
- Hypercalcemia risk if total calcium intake is excessive
Contraindications
- Hypercalcemia or conditions predisposing to high calcium levels1,5
- History of calcium-containing kidney stones (use caution)1,5
- Severe renal impairment (impaired calcium and mineral handling)
- Hyperparathyroidism or sarcoidosis without medical supervision
- Pregnancy and breastfeeding (insufficient safety data for supplemental use)
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Randomized controlled trials
1- 1Calcium alpha-ketoglutarate in the treatment of postmenopausal osteoporosisFilip RS et al. · Endocrine Regulations · 2007
Supplementation with calcium alpha-ketoglutarate was associated with improvements in bone mineral density compared with control in postmenopausal women.
Reviews & position papers
3- 2Alpha-ketoglutarate supplementation and skeletal and metabolic effects in humans and animal models: a systematic reviewBayliak MM, Lushchak VI · Ageing Research Reviews · 2021
- 3Alpha-ketoglutarate: physiological functions and applicationsWu N et al. · Biomolecules and Therapeutics · 2016
AKG serves as a required co-substrate for 2-oxoglutarate-dependent dioxygenases including TET DNA demethylases and Jumonji histone demethylases, providing a mechanistic link between cellular metabolism and epigenetic state.
- 4Alpha-ketoglutarate as a molecule with pleiotropic activity: from metabolism to epigenetic regulationWu N, Yang M, Gaur U, Xu H, Yao Y, Li D · Aging and Disease · 2016
Observational studies
2- 5Reversal of biological age in subjects taking calcium alpha-ketoglutarate (Rejuvant)Demidenko O et al. · Aging (Albany NY) · 2021
In 42 participants taking calcium-AKG, average DNA-methylation age decreased by roughly 8 years over about 7 months of use; uncontrolled design limits causal interpretation.
- 6Influence of calcium alpha-ketoglutarate supplementation on biological age as measured by DNA methylation in healthy adultsSource linkedPMIDDemidenko O, Barardo D, Budovskii V, Finnemore R, Palmer FR 3rd, Kennedy BK, Budovsky A, Fraifeld VE, Zhavoronkov A · Aging (Albany NY) · 2021
Mechanistic & preclinical
2- 7Alpha-ketoglutarate, an endogenous metabolite, extends lifespan and compresses morbidity in aging miceShahmirzadi AA et al. · Cell Metabolism · 2020
Calcium alpha-ketoglutarate supplementation begun in mid-to-late life decreased frailty and markers of inflammation and extended healthspan, with a modest effect on lifespan.
- 8Alpha-ketoglutarate prevents age-related bone loss and stimulates osteoblast differentiationRadzki RP, Bienko M, Filip R, et al. · Journal of Bone and Mineral Metabolism · 2012
Common questions.
Quick answers about Calcium Alpha-Ketoglutarate, drawn from the data on this page.
What is Calcium Alpha-Ketoglutarate?
Calcium alpha-ketoglutarate is a calcium salt of alpha-ketoglutarate (AKG), a central intermediate of the Krebs (TCA) cycle that links carbon, nitrogen, and energy metabolism. It is marketed (notably as Rejuvant) as a longevity supplement intended to support healthy aging via metabolic and epigenetic pathways. Interest is driven by mouse studies showing extended healthspan and a small open-label human trial reporting reductions in DNA-methylation biological age, though rigorous controlled human evidence remains preliminary.
What is Calcium Alpha-Ketoglutarate used for?
Commonly cited benefits of Calcium Alpha-Ketoglutarate include: May support healthy aging and reduce biological (epigenetic) age markers; Provides bioavailable calcium for bone and muscle support; Supports cellular energy metabolism as a TCA-cycle intermediate; May reduce markers of systemic inflammation; Investigated for support of muscle and physical function in aging. NutriStack rates the overall evidence as emerging.
What is a typical dose of Calcium Alpha-Ketoglutarate?
A typical adult dose of Calcium Alpha-Ketoglutarate is 1000-3000 mg per day of calcium alpha-ketoglutarate, often split into two doses (the Rejuvant protocol uses about 1000 mg twice daily). The commonly recommended form is Calcium alpha-ketoglutarate powder in capsules; sustained or divided dosing is commonly used. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of Calcium Alpha-Ketoglutarate?
Reported side effects include generally well tolerated in short-term studies, mild gastrointestinal upset, nausea, or bloating, possible constipation from the calcium content, hypercalcemia risk if total calcium intake is excessive. This is educational information; check with a healthcare professional before use.
How strong is the evidence for Calcium Alpha-Ketoglutarate?
NutriStack rates this as Emerging, meaning early RCT signal, mechanistic data, or limited human evidence. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
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