Longevity Foundation Stack.

NMN is one step from NAD+, the cofactor that sirtuins and PARPs consume and that the citric acid cycle reduces. NAD precursors are the backbone of this category of formula.

Nicotinamide riboside is phosphorylated by NRK enzymes into NMN and then into NAD+, refilling the same pool. It is the other standard precursor alongside NMN.

Excess nicotinamide is cleared by nicotinamide N-methyltransferase, which spends a methyl group from S-adenosylmethionine on each molecule. Betaine remethylates homocysteine back to methionine and so replaces the methyl groups that heavy NAD precursor dosing draws down.

Stilbenes act on sirtuins, which cannot deacetylate anything without NAD+. Pairing a stilbene with an NAD precursor supplies the enzyme signal and its consumable cofactor together.

Resveratrol acts on the same sirtuin and AMPK axis as pterostilbene but is cleared much faster by glucuronidation. It is the older member of the same pairing with NAD precursors.

Glycine and cysteine are the two amino acids whose supply limits glutathione synthesis, and glycine intake commonly falls short of what collagen turnover and conjugation demand. It is paired with a cysteine donor for that reason.

Cysteine is the rate-limiting amino acid for glutathione, and NAC delivers it in a stable form. Combined with glycine it addresses both limiting inputs of the same tripeptide.

Alpha-ketoglutarate is a citric acid cycle intermediate and the co-substrate of the dioxygenase family that demethylates DNA and histones. It sits on the same metabolic and epigenetic axis these formulas are built around.

Ubiquinol carries electrons between complexes I and II and complex III and is the main lipid-phase antioxidant of the inner mitochondrial membrane. It complements the NAD axis, which supplies the electrons entering at complex I.

Spermidine inhibits the acetyltransferase EP300 and so removes a brake on autophagy, a different lever from the NAD and sirtuin axis. The two mechanisms converge on cellular housekeeping.

Urolithin A, made by gut bacteria from pomegranate ellagitannins, acts on mitophagy, the selective clearance of worn mitochondria. It complements cofactor supply, which acts on the mitochondria that remain.

Fisetin acts on the survival signalling that keeps senescent cells in place, a separate axis from cofactor supply or autophagy. It is a standard companion in this class of formula.

Quercetin is the other well-known flavonol on the senescent cell survival axis and it also slows the conjugating enzymes that clear stilbenes, raising their exposure. Both effects fit alongside the NAD and sirtuin core.

Taurine conjugates bile acids, stabilises mitochondrial tRNA modification and buffers osmotic and calcium load, and circulating levels fall with age. It is a common component of this formula class on that basis.

Calcitriol acts through a nuclear receptor that sets transcription of calcium handling, muscle and immune-cell genes across most tissues. It is the foundational nutrient layer under any formula of this type.

NAD kinase, the enzyme that phosphorylates NAD to NADP, requires magnesium, as do the ATP-dependent steps in every salvage route to NAD. A stack built on NAD precursors depends on magnesium status to convert them. This is cofactor biochemistry and needs no trial.

Vitamin K is the cofactor for the carboxylase that activates matrix Gla protein and osteocalcin, the proteins that direct calcium into bone and hold it out of arterial wall tissue. Vitamin D raises calcium absorption but does not decide where it goes. Pairing the two is the standard reasoning in any stack carrying vitamin D.

EPA and DHA are incorporated into membrane phospholipids and are the substrates for resolvins and protectins, the signals that wind down an inflammatory response. Cohort studies associate higher omega-3 status with several markers of biological ageing, and an association is not a cause. The mechanism sits apart from the NAD and methylation arms of a longevity stack.

5-methyltetrahydrofolate donates the methyl group that regenerates methionine from homocysteine, refilling the SAM pool. High-dose nicotinamide precursors consume SAM because excess nicotinamide is methylated for excretion. Folate supply is one of the routes that keeps the methyl budget in balance.

Methionine synthase needs methylcobalamin to transfer the methyl group from folate to homocysteine. Without B12 the folate cycle traps methyl groups and the methionine regeneration step stalls. Any stack that adds methyl demand depends on this enzyme working.

Pyridoxal 5-phosphate drives the transsulfuration route that clears homocysteine into cysteine and onward into glutathione. It is the exit that folate and B12 do not provide, since those only recycle homocysteine back to methionine. Both routes matter when methyl demand rises.

Choline is oxidised to betaine, which methylates homocysteine through BHMT independently of folate. It therefore supports the same methyl pool that trimethylglycine does, from an upstream position. Choline also has structural duties in phospholipid synthesis that betaine cannot cover.

Nicotinic acid enters NAD synthesis through the Preiss-Handler route, a different entry point from the nicotinamide riboside and mononucleotide salvage steps. It reaches the same cofactor pool by another door. At gram doses nicotinic acid causes flushing and draws on methylation for excretion, which is why nutritional and pharmacological amounts are not interchangeable.

Lipoic acid is the cofactor for pyruvate and alpha-ketoglutarate dehydrogenase, both NAD-dependent complexes, and its reduced form regenerates vitamins C and E. It touches mitochondrial energy handling and the antioxidant network at once. That places it alongside rather than downstream of the NAD precursors.

Creatine buffers cellular ATP through the phosphocreatine system, supporting energy availability in muscle and brain. Its synthesis is one of the largest consumers of SAM in the body, so supplementing it spares methyl groups. Both effects are relevant in a stack carrying methylation-demanding compounds.

Collagen peptides supply glycine, proline and hydroxyproline, the amino acids that make up the collagen triple helix. Glycine is already in this stack for glutathione synthesis, and collagen intake pushes the same amino acid pool. Vitamin C is required for the hydroxylation step that stabilises new collagen.

Sulforaphane is one of the strongest known dietary activators of Nrf2, which raises transcription of glutathione and thioredoxin system enzymes. That is an induction mechanism, distinct from the direct precursor supply that NAC and glycine provide. Induction plus substrate is a coherent pairing on established signalling biology.

Astaxanthin spans the lipid bilayer with polar ends on both faces, which lets it quench radicals at the membrane surface and in the core. Water-soluble constituents of a longevity stack cannot reach that position. Absorption requires dietary fat in the same meal.

Carnitine shuttles long-chain fatty acids into mitochondria for beta-oxidation, which feeds NADH into the electron transport chain. Its own synthesis needs SAM, iron and vitamin C. Both facts place it inside the same metabolic budget the rest of the stack draws on.

Selenocysteine sits in the active site of glutathione peroxidases and thioredoxin reductases, the enzymes that recycle the antioxidant pool this stack supplies precursors for. Precursor supply without cofactor supply leaves the enzymes short. Selenium also has a narrow intake range, so total intake from all sources is what to count.

Zinc is structural or catalytic in hundreds of enzymes including superoxide dismutase 1, and it is needed for DNA repair enzyme function. Sustained zinc supplementation lowers copper status through metallothionein induction, so a small copper allowance usually accompanies it. Both facts are established mineral pharmacology.

Copper and zinc compete for the same intestinal handling through metallothionein, so a stack carrying meaningful zinc drives copper status down over months. Copper is itself required for cytochrome c oxidase and for extracellular superoxide dismutase. The interaction is directional and well characterised.

Curcuminoids act on Nrf2 and NF-kB signalling in cell models and are among the polyphenols most often grouped with resveratrol and pterostilbene. All three share poor water solubility and heavy first-pass conjugation. Combining them raises the total load on the same clearance enzymes.

Coenzyme Q10 carries electrons between complexes I and III of the respiratory chain, the point at which NADH is oxidised back to NAD. A stack raising NAD availability depends on that chain being able to accept the electrons. Absorption is fat dependent regardless of which redox state is used.

Ascorbate is the required cofactor for the prolyl and lysyl hydroxylases that stabilise collagen, and for the TET dioxygenases and JmjC demethylases that act on DNA and histone methyl marks. That places it directly inside the epigenetic machinery a longevity stack is aimed at. It also regenerates oxidised tocopherol.