1-Methylnicotinamide
1-MNA · MNA · MeNAM · N1-methylnicotinamide · MNAM · Pelnar
Last updated
At a glance
Overview
1-Methylnicotinamide has quietly become the cardiovascular adjunct of choice for physique-focused users running aggressive cycles. Reframed from "inert metabolite" to bioactive signaling molecule by the Jagiellonian / Chlopicki group, 1-MNA drives endothelial prostacyclin (PGI₂) release, upregulates DDAH-2 to clear the eNOS inhibitor ADMA, and restores NO bioavailability in vessels stressed by orals, hypertension, or metabolic load. It is the practical answer to the question "what do I run alongside my AAS to protect the endothelium without flushing like niacin?"
The community uses it across several lanes — on-cycle blood-pressure and endothelial coverage during heavy oral stacks, a no-flush alternative for users who can't tolerate nicotinic acid, an endurance-recovery hedge in extended cardio blocks, and a longevity-tier daily for users stacking it with tadalafil, bergamot, and an NAD⁺ precursor. Critically, 1-MNA is not a NAD⁺ booster — vendors who pitch it as an NMN substitute are misrepresenting the mechanism. The value is vascular, not NAD-restorative.
"1-MNA is no longer considered an inert biomarker, but rather an active signaling molecule with evidence supporting its role in improving endothelial function, reducing inflammation, and modulating cardiovascular risk." — Yalameha & Nejabati, Clinica Chimica Acta (2023)
The sections below cover documented 1-methylnicotinamide dosage ranges, the COX-2 / PGI₂ and ADMA-DDAH mechanism in detail, a tiered protocol for on-cycle endothelial support, the stack logic alongside tadalafil and bergamot, side effects including the additive antiplatelet consideration, and the human evidence base anchored by the Pharmena novel-food dossier.
How 1-Methylnicotinamide works
NNMT Origin and the PGI₂ Pathway#
1-MNA is the N-methylated metabolite of nicotinamide, produced endogenously by nicotinamide N-methyltransferase (NNMT) using S-adenosyl-methionine as the methyl donor. For decades it was dismissed as an inert excretion product — the Chlopicki group at Jagiellonian University reframed it as a bioactive endothelial signalling molecule with measurable downstream effects on platelet activity, NO availability, and vascular inflammation.
The dominant arm is COX-2-mediated prostacyclin (PGI₂) release. Oral 1-MNA stimulates endothelial COX-2, raising plasma 6-keto-PGF1α (the stable PGI₂ metabolite). PGI₂ suppresses platelet aggregation, opposes thromboxane A₂, and inhibits vascular smooth muscle proliferation — the same axis that low-dose aspirin manipulates from the opposite direction.
"1-MNA at doses of 100–500 mg/kg administered orally or intravenously significantly increased the plasma level of 6-keto-PGF1α, the stable metabolite of prostacyclin, and strongly inhibited thrombus formation in vivo via a prostacyclin-dependent mechanism." — Chlopicki S. et al. British Journal of Pharmacology, 2007
The practical translation for physique-focused users: this is the arm that matters on cycle. Oral AAS shift the platelet/PGI₂ balance toward thrombosis, and 1-MNA pushes it back without the GI and bleeding profile of chronic aspirin.
NO Bioavailability via the ADMA–DDAH Axis#
Chronic 1-MNA administration upregulates DDAH-2 (dimethylarginine dimethylaminohydrolase-2), the enzyme that clears asymmetric dimethylarginine (ADMA) — the endogenous inhibitor of endothelial nitric oxide synthase (eNOS). Lower ADMA means more functional eNOS, which means restored NO bioavailability and reversed endothelial dysfunction.
"Chronic administration of 1-MNA restored endothelial function in ApoE-knockout mice, likely via normalization of NO bioavailability through reduction of plasma asymmetric dimethylarginine (ADMA) levels." — Mateuszuk Ł. et al. Pharmacological Reports, 2009
This is why 1-MNA stacks logically with low-dose tadalafil: tadalafil potentiates downstream NO signalling via PDE5 inhibition, while 1-MNA increases the upstream NO substrate pool. Two different points of attack on the same pathway — relevant for blood pressure management on heavy oral cycles and for pump quality during training.
Sirt1 / Nrf2 / HO-1 Anti-Inflammatory Signalling#
Beyond the platelet and NO arms, the NNMT/1-MNA axis modulates Sirt1 activity, dampens NF-κB-driven inflammatory transcription, and induces Nrf2-driven antioxidant gene expression (HO-1, NQO1). This is the arm responsible for the gastroprotective, hepatoprotective, and anti-inflammatory effects documented across concanavalin-A hepatitis, ischemia-reperfusion, and homocysteine-induced endothelial injury models.
"1-MNA is no longer considered an inert biomarker, but rather an active signaling molecule with evidence supporting its role in improving endothelial function, reducing inflammation, and modulating cardiovascular risk." — Yalameha B, Nejabati HR. Clinica Chimica Acta, 2023
For users running heavy orals or high-dose GH, the relevance is systemic inflammatory load — hsCRP and homocysteine are the practical readouts the community tracks.
Exercise Capacity and Endothelial Reserve#
The Przyborowski 2015 work in diabetic mice demonstrated that chronic 1-MNA preserves endothelial responsiveness to exercise and extends time-to-fatigue, with reduced post-exercise leukocytosis.
"Chronic MNA supplementation improved exercise capacity and endothelial response in diabetic mice, as measured by prolonged time to fatigue and protection against endothelial dysfunction following aerobic exercise." — Przyborowski K. et al. PLoS One, 2015
The mechanism stacks the PGI₂ and NO arms together: better vasodilatory reserve during exertion, faster recovery of endothelial function afterwards. Translated to lifters and endurance-focused users, this is the rationale for pre-cardio dosing during cutting blocks or extended LISS phases.
What 1-MNA Is Not#
A persistent point of confusion: 1-MNA is not a NAD⁺ precursor. It sits downstream of NAD⁺ salvage and is excreted via urinary clearance (parent compound plus the Met-2-PY and Met-4-PY pyridone metabolites produced by hepatic aldehyde oxidase). Vendors and marketers conflate it with NMN (nicotinamide mononucleotide) because the names look similar — they are chemically and mechanistically distinct molecules. The vascular activity of 1-MNA is independent of any NAD⁺-boosting effect, and dosing it will not move NAD⁺ status. Treat it as a cardiovascular and anti-inflammatory adjunct, not a sirtuin-fuel longevity compound.
Protocol
| Level | Dose | Frequency | Notes |
|---|---|---|---|
| Low | 50–100 mg | Twice daily | Documented entry-level range |
| Mid | 200–400 mg | Twice daily | Most commonly studied range |
| High | 500–1000 mg | Twice daily | Short half-life (~3–5 h) favors AM/PM split dosing for chronic endothelial coverage. Empty-stomach administration accelerates Tmax; food blunts but does not abolish absorption. |
Cycle length & outcomes
Documented cycle
4–16 weeks
Plateau after
12 wks
Cycle Notes#
1-MNA is a chronic-dosing endothelial adjunct, not a pulsed longevity compound. The mechanism — sustained DDAH-2 upregulation, steady PGI₂ tone, NF-κB suppression — requires weeks of continuous exposure to manifest. Unlike rapamycin or NAD⁺ precursors, there is no rationale for cycling on/off; protocols run alongside the cardiovascular stressor (AAS cycle, oral-heavy block, heavy cardio phase) and taper out 4–6 weeks past the stressor.
The short half-life (~3–5 h) is the single most important practical variable. Single morning dosing leaves the back half of the day uncovered. AM/PM split dosing is the default.
| Goal | Cycle Length | Daily Dose |
|---|---|---|
| General endothelial / longevity support | 8–16 weeks (open-ended) | 58–100 mg once daily |
| No-flush niacin alternative (inflammation, hsCRP) | 8–12 weeks | 100 mg AM + 100 mg PM |
| On-cycle support, mild AAS / TRT-plus | Duration of cycle + 4 weeks | 100 mg AM + 100 mg PM |
| On-cycle support, oral-heavy or blast | Duration of cycle + 4–6 weeks | 200 mg AM + 200 mg PM |
| Advanced (heavy AAS, hypertensive responder, GH stack) | Duration of cycle + 6 weeks | 300 mg AM + 300 mg PM |
| Endurance / LISS cardio block | 4–8 weeks | 100 mg pre-cardio + 100 mg PM |
"No adverse effects were observed in human trials at 90 mg and 270 mg daily for 12 weeks, with a safety margin supported by genotoxicity and chronic toxicity studies in animals." — Pharmena S.A., UK Food Standards Agency Novel Food Dossier (2013)
The 270 mg/day human safety ceiling is the most-defensible upper bound for conservative protocols. Community dosing above this is extrapolated from animal toxicology in the same dossier (NOAEL well above 1 g/kg in rodents) and remains uncharacterized in human trials — informed users running 600–1,000 mg/day are operating beyond the published human envelope, even if the toxicology margin appears wide.
Onset and Time-to-Effect#
- Acute PGI₂ release: within hours of the first dose, demonstrable as elevated 6-keto-PGF1α in plasma. Functionally invisible to the user.
- hsCRP / inflammatory markers: measurable shifts at 3–4 weeks of consistent BID dosing.
- Endothelial function (flow-mediated dilation, ADMA clearance): 4–8 weeks. This is the timeframe the Mateuszuk ApoE-knockout data implies for the DDAH-2 / ADMA arm.
- Blood pressure / pump quality on cycle: subjective reports cluster around week 2–3, generally subtle and additive on top of tadalafil or telmisartan rather than standalone.
"Chronic administration of 1-MNA restored endothelial function in ApoE-knockout mice, likely via normalization of NO bioavailability through reduction of plasma asymmetric dimethylarginine (ADMA) levels." — Mateuszuk et al., Pharmacological Reports (2009)
Loading and Tapering#
No loading phase. Plasma 1-MNA reaches steady-state within 24–48 h of BID dosing given the 3–5 h half-life. Front-loading offers no kinetic benefit.
No taper required. The compound does not suppress endogenous pathways, does not require HPTA recovery, and has no rebound profile. Discontinuation at the end of a protocol is abrupt and uneventful. The reason to extend dosing 4–6 weeks past the end of an AAS cycle is that endothelial recovery from oral-driven dyslipidemia and BP elevation lags the steroid washout — not because of any 1-MNA-specific taper requirement.
On-Cycle Bloodwork Cadence#
For users running 1-MNA as the cardiovascular adjunct on a 12–16 week AAS cycle, the relevant panel is the standard on-cycle workup rather than anything 1-MNA-specific:
- Baseline (week –2 to 0): CBC, CMP, full lipid panel, hsCRP, homocysteine, resting BP log (7-day average).
- Mid-cycle (week 6–8): repeat lipid panel, hsCRP, BP. This is where the 1-MNA arm should be visible — hsCRP and homocysteine trending down, BP holding flatter than expected for the AAS load.
- End-of-cycle / 4 weeks post: full panel repeat. Endothelial markers should be returning to baseline faster than on a comparable cycle run without endothelial support.
There is no commercially available 1-MNA plasma assay outside research settings. Urinary 1-MNA exists as a niacin-status biomarker but is not useful for titrating supplemental dosing.
Stacking Inside the Cycle#
The compound layers cleanly onto the standard on-cycle cardiovascular stack and is mechanistically complementary rather than redundant:
- Tadalafil 2.5–5 mg/day — PDE5-driven NO arm pairs with 1-MNA's ADMA-clearance arm.
- Telmisartan 20–40 mg/day — for users whose BP creeps past 140/90 on cycle.
- Citrus bergamot 500 mg BID + EPA-heavy fish oil — lipid arm, since 1-MNA does not meaningfully shift HDL or Lp(a).
- Low-dose aspirin (81 mg) — mechanistically additive on the antiplatelet side; acceptable for most users but the additive bleeding-risk window matters around dental work or surgery. Discontinue both 7–10 days prior to any procedure.
The protocol ends when the cardiovascular stressor ends. For a 16-week blast, that means 16 weeks of BID dosing plus a 4–6 week trailing phase into PCT — roughly 20–22 weeks of continuous exposure, well within the duration envelope characterized in the Pharmena human safety work.
Risks & mistakes
Common (most users)#
- Mild GI discomfort / nausea — most often at doses ≥200 mg or on an empty stomach. Splitting the daily dose AM/PM and pairing with a small meal resolves it; food blunts Tmax slightly but does not meaningfully reduce coverage given the chronic dosing pattern.
- Transient headache — low-grade vasodilatory headache occasionally reported during the first week of higher-dose protocols (300+ mg/day). Distinct from the GPR109A cutaneous flush of nicotinic acid. Hydration and a brief dose taper (start at 50–100 mg/day for 5–7 days, then titrate up) eliminate it in most subjects.
- Subjective "warmth" or facial flushing — uncommon and mild; not the classic niacin flush. Self-limiting within 1–2 weeks of chronic dosing.
"No adverse effects were observed in human trials at 90 mg and 270 mg daily for 12 weeks, with a safety margin supported by genotoxicity and chronic toxicity studies in animals." — Pharmena S.A., UK Food Standards Agency Novel Food Dossier (2013)
Uncommon (dose-dependent or individual)#
- Prolonged bleeding time / easier bruising — mechanistically expected at the upper end of community dosing (500–1,000 mg/day) given PGI₂-mediated platelet inhibition. Back off to 100–200 mg/day if nosebleeds, gum bleeding, or unusual bruising appear, particularly when stacked with low-dose aspirin for hematocrit management on cycle.
- Mild BP drop on standing — occasional in lean, well-conditioned subjects already running tadalafil or telmisartan. If lightheadedness on standing presents, reduce the PM dose and re-check resting BP after 1–2 weeks.
- Bloodwork to monitor at higher doses: CBC (platelet count, hematocrit), CMP (creatinine — renal clearance pathway), hsCRP and homocysteine as efficacy readouts. No hepatic signal has been documented, but on-cycle panels already cover ALT/AST.
Rare but serious#
- Clinically significant bleeding — not reported in human trials at supplemental doses, but mechanistically plausible when combined with therapeutic anticoagulation, high-dose NSAIDs, or P2Y12 inhibitors. Warning signs: melena, hematuria, prolonged epistaxis, or any unexplained bruising over joints. Discontinue immediately.
- Hypotensive episode — theoretical, primarily a stacking issue when 1-MNA sits alongside tadalafil, an ARB, and a beta-blocker. Symptomatic hypotension warrants dose reduction across the stack, not just 1-MNA.
Hard contraindications#
- Therapeutic anticoagulation (warfarin at target INR, DOACs, therapeutic-dose LMWH) — additive antithrombotic effect.
- Scheduled major surgery — discontinue 7–10 days prior, same logic applied to aspirin.
- Pregnancy and lactation — not characterized; the supplement label explicitly excludes these populations and the community follows suit.
- Severe renal impairment (CKD stage 4–5) — 1-MNA and its pyridone metabolites already accumulate in advanced CKD independent of supplementation; adding exogenous load is not appropriate.
- Active peptic ulcer disease on dual antiplatelet therapy — the additive antiplatelet effect outweighs any gastroprotective signal seen in animal models.
Gender, hormonal, and PCT considerations#
1-MNA is non-hormonal — no interaction with the HPTA, aromatase, 5α-reductase, SHBG, or androgen receptor signaling. Dosing is uniform across the subject pool; no virilization risk, no menstrual cycle considerations, and no PCT requirement. The compound can be run continuously through a cycle and into recovery without affecting endogenous testosterone restoration. Reproductive toxicity studies in the Pharmena dossier were clean, but the label excludes pregnancy and lactation by convention rather than by signal — the community does the same.
FAQ — 1-Methylnicotinamide
Research & citations
6 studies cited on this page.
Conclusion
1-MNA stands out as a true endothelial support compound in the longevity and cardiovascular-adjunct tier — not a NAD⁺ booster, but a direct PGI₂/NO pathway modulator backed by solid mechanistic and preclinical evidence.
Key takeaways:
- Documented dose range: 100–400 mg/day (58–200 mg BID is typical), orally
- Short half-life (~3–5 hours) favors twice-daily split dosing for sustained vascular coverage
- Core mechanisms: prostacyclin (PGI₂) upregulation, ADMA clearance for NO restoration, and anti-inflammatory Sirt1/Nrf2 signaling
- Optimal stacking: low-dose tadalafil, citrus bergamot, ARB or ACEi, and EPA-rich fish oil for comprehensive on-cycle cardiovascular protection
- Common cycle length: 8–16 weeks (on-cycle and early PCT) with no PCT required
- Excellent safety profile in published trials up to 270 mg/day, with only mild GI symptoms rarely observed (Pharmena dossier, 2013)
For users looking to mitigate AAS-driven endothelial stress or upregulate cardiovascular resilience in a daily longevity stack, 1-MNA delivers a focused, mechanistically distinct benefit with minimal baggage.