NAD+
Nicotinamide Adenine Dinucleotide · NAD · Coenzyme I · β-NAD+ · DPN
Last updated
At a glance
Overview
Why NAD+ Matters#
NAD+ is the cofactor that runs your mitochondria, feeds your sirtuins, and fuels PARP-mediated DNA repair. It declines steadily with age — partly because CD38, a membrane NADase, ramps up with inflammation and chronological aging — and that decline tracks closely with the metabolic slowdown, slower recovery, and flatter energy most people blame on "just getting older." Restoring it is the entire point of the longevity-peptide movement, and injectable NAD+ is the most direct way to do that.
"Sirtuin activity is directly dependent on NAD+ availability, which declines with age and is associated with metabolic and cardiovascular dysfunction." — Kane & Sinclair, Circulation Research (2018)
The bodybuilding and looksmaxxing community has adopted NAD+ for three overlapping reasons: post-cycle mitochondrial and hepatic recovery after heavy orals, endurance and conditioning support via the sirtuin–PGC-1α axis, and general longevity maintenance (energy, sleep quality, skin, cognition) stacked alongside NR/NMN, rapamycin, and the usual peptide rotation. It's non-hormonal, requires no PCT, doesn't aromatize, and sits cleanly next to every other compound you might be running. The catch is delivery: oral NAD+ is effectively useless — it's hydrolyzed in the gut before it ever sees your bloodstream — so the real protocol is either subcutaneous injection or a slow IV drip, and infusion rate is the entire tolerability story.
Below, we break down the NAD+ dosage ladder (SC vs IV vs oral precursors), protocol design for recovery, endurance, and longevity goals, the stack most experienced users run it inside, realistic expectations grounded in the human evidence rather than the clinic marketing, and the side-effect profile — including why that "elephant on the chest" sensation happens and how to avoid it entirely.
How NAD+ works
NAD+ isn't a hormone, a peptide, or a signaling molecule in the conventional sense — it's a redox cofactor that every cell in your body burns through by the millisecond. Raising it doesn't "do" one thing; it unlocks bandwidth across three enzyme classes that together govern mitochondrial output, DNA repair, and the sirtuin axis. Understanding which lever you're pulling is the difference between a coherent longevity protocol and $800 drip-clinic theater.
Redox Cofactor and Mitochondrial ATP Output#
The oldest job NAD+ has is shuttling electrons. Every step of glycolysis, β-oxidation, and the TCA cycle dumps electrons onto NAD+ to form NADH, which then feeds Complex I of the electron transport chain to drive ATP synthesis. Without enough oxidized NAD+ on hand, glycolytic flux stalls — not because ATP is low, but because there's nowhere to park the electrons.
"Regeneration of NAD+ is a more important determinant of glycolytic flux than ATP in proliferating cells, underscoring the fundamental metabolic role of NAD+ availability." — Luengo, A. et al. Molecular Cell, 2021
Practically: repleting NAD+ in a mitochondrially-stressed tissue (post-cycle liver, aging skeletal muscle, a hungover brain) restores the oxidative capacity ceiling. This is the mechanism behind the "cleaner energy" subjective report users describe after SC injections or slow IVs — not stimulation, but the removal of a redox bottleneck.
Sirtuin Cosubstrate — The PGC-1α / Mitochondrial Biogenesis Axis#
SIRT1–SIRT7 are a family of NAD+-dependent deacylases. They strip acetyl groups off lysine residues on dozens of regulatory proteins — PGC-1α, FOXO3a, p53, NF-κB, and the histones wrapped around your metabolic genes. Every deacylation reaction consumes one molecule of NAD+, which is why sirtuin activity is rate-limited by NAD+ availability rather than by sirtuin expression.
"Sirtuin activity is directly dependent on NAD+ availability, which declines with age and is associated with metabolic and cardiovascular dysfunction." — Kane, A.E. & Sinclair, D.A. Circulation Research, 2018
The downstream payoff is SIRT1/SIRT3 activation of PGC-1α — the master regulator of mitochondrial biogenesis. This is the same pathway that endurance training and cold exposure upregulate. Stacking NAD+ repletion onto a real cardio block is the coherent play; pinning NAD+ while sedentary activates the machinery with nothing to remodel.
PARP, DNA Repair, and the Cost of Genotoxic Stress#
Poly(ADP-ribose) polymerases (PARP1/2) are the frontline DNA damage sensors. When they detect single- or double-strand breaks, they consume NAD+ at ferocious rates to build PAR chains that recruit the repair machinery. A single genotoxic insult — UV, alcohol, oxidative damage from a hard orals cycle — can drain cellular NAD+ by 20–40% within hours.
This matters for two audiences specifically:
- Lifters running methylated orals or high-dose AAS. Hepatocyte oxidative stress activates PARP heavily; NAD+ repletion pairs mechanistically with TUDCA and NAC for post-cycle liver recovery.
- Looksmaxxers running MT-II, sun-chasing, or aggressive skin protocols. UV damage means PARP activation in keratinocytes and fibroblasts; NAD+ is the substrate those cells need to actually repair rather than apoptose.
CD38, NAMPT, and Why NAD+ Crashes With Age#
You don't need to supplement NAD+ when you're 22 because NAMPT — the rate-limiting salvage enzyme — regenerates it from nicotinamide fast enough to keep up with consumption. The age-related crash is driven on the consumption side by CD38, a membrane-bound NADase that climbs with age and chronic inflammation.
"CD38, a membrane NADase upregulated during aging and inflammatory conditions, has been shown to drive the age-related decline in NAD+." — Peng, A. et al. Frontiers in Molecular Biosciences, 2024
This is why oral NAD+ is a scam and parenteral NAD+ has a ceiling: extracellular CD38 chews through circulating NAD+ before most of it reaches target tissues. The Grant 2019 IV study made this visible — plasma NAD+ didn't rise measurably until ~2 hours into a 6-hour drip, while downstream metabolites (methyl-nicotinamide, ADPR) appeared within minutes, i.e. the body was shredding NAD+ on arrival.
"Plasma concentrations of NAD+ did not rise significantly until approximately 2 hours into the infusion, while downstream metabolites such as methyl-nicotinamide and ADPR were detected much earlier." — Grant, R. et al. Frontiers in Aging Neuroscience, 2019
The practical takeaway: slow, sustained delivery (4+ hour IV, or SC 2–3×/week) lets tissue uptake compete with CD38 degradation. Bolus dosing doesn't.
Why Oral "NAD+" Fails — and What Actually Works Orally#
NAD+ is a 663 Da charged dinucleotide. The gut hydrolyzes it on contact; there is no NAD+ transporter designed to move the intact molecule across the enterocyte membrane. Capsules labeled "NAD+" deliver, at best, nicotinamide — which then has to re-enter the salvage pathway like any other precursor.
"Orally administered 'NAD+' is rapidly hydrolyzed and does not increase blood NAD+ levels; NR 1000 mg/d results in 2-fold increases in whole blood NAD+ concentrations." — Mehmel, M. et al. Science Advances, 2024
This is the entire mechanistic argument for the standard longevity stack: oral NR or NMN to keep the salvage pathway substrate-loaded between injections, plus SC or slow IV NAD+ to directly bump circulating and tissue pools. The two routes are complementary, not redundant — NR/NMN feed NAMPT, parenteral NAD+ bypasses it. Run both and you're attacking the age-related decline from supply and demand sides simultaneously.
Protocol
| Level | Dose | Frequency | Notes |
|---|---|---|---|
| Low | 50–100 mg | Twice weekly | Documented entry-level range |
| Mid | 100–250 mg | Twice weekly | Most commonly studied range |
| High | 250–1000 mg | Twice weekly | Community SC protocol: 50–100 mg SC 2–3×/week. Clinic IV: 250–1000 mg per session, infused slowly (≥4 hours) — infusion rate is the entire tolerability story. Oral NAD+ is effectively useless; use NR/NMN as the oral route. |
Cycle length & outcomes
Documented cycle
4–52 weeks
Plateau after
12 wks
Cycle Length & Protocol#
NAD+ doesn't cycle like an anabolic. It's a cofactor — you're refilling a tank that drains continuously with age, inflammation, training load, and alcohol. There's no HPTA to suppress, no receptor to desensitize, no PCT. The practical question isn't "how long can I run it" but "what cadence matches the goal."
| Goal | Cycle Length | Dose & Route |
|---|---|---|
| Post-cycle liver/mitochondrial recovery | 4–6 weeks | 100 mg SC 3×/week |
| Endurance & mitochondrial biogenesis block | 6–8 weeks | 50–100 mg SC 2×/week |
| Cognitive / jet-lag / high-demand reset | 3–5 days (loading) | 500–750 mg slow IV daily (≥4 hr) |
| Longevity maintenance | Indefinite | 50 mg SC 2×/week, or 500 mg slow IV monthly |
| Hangover / acute recovery | Single dose | 250–500 mg slow IV, or 100 mg SC |
Loading vs Maintenance#
The addiction-medicine and longevity-clinic playbook is a 5–10 day IV loading block (500–1000 mg/day, slow drip) followed by weekly or monthly maintenance. There's no pharmacological requirement to load — you can run steady-state SC from day one and get to the same place — but a loading block is where users report the clearest subjective shift in energy, sleep, and clarity. If you're paying clinic prices, a loading block is the only way an IV protocol makes economic sense vs SC maintenance SC.
No taper is needed at the end of a cycle. NAD+ doesn't downregulate anything you'd miss on discontinuation.
Onset Timing#
- IV: Plasma NAD+ itself doesn't rise measurably until ~2 hours into the infusion, though downstream metabolites appear earlier — meaning a 1-hour drip is mostly metabolites, not NAD+ repletion.
"Plasma concentrations of NAD+ did not rise significantly until approximately 2 hours into the infusion, while downstream metabolites such as methyl-nicotinamide and ADPR were detected much earlier." — Grant et al., Frontiers in Aging Neuroscience (2019)
This is the entire argument for slow drips: you need the infusion to outlast first-pass consumption by CD38 and ectoenzymes before intracellular stores actually start filling.
- SC: Subjective effects (energy, sleep depth, training recovery) typically show up in the second week of 2–3×/week dosing. Don't judge SC on the first couple of injections.
- Loading blocks: Most users report the clearest shift around days 3–5 of a daily IV loading protocol.
Bloodwork Cadence#
NAD+ is non-hormonal and doesn't affect lipids, liver enzymes, hematocrit, or the HPTA, so the usual on-cycle panel isn't required for NAD+ itself. Practical markers:
- Annual CMP/CBC/lipids as baseline health hygiene.
- hs-CRP if stacking with other anti-inflammatory peptides — useful for tracking the net inflammatory picture.
- Intracellular NAD+ assays (Jinfiniti and similar) exist but signal-to-noise is debated; most experienced users track subjective energy, sleep quality, and recovery instead of chasing a number.
If you're running NAD+ alongside AAS, orals, or a heavy peptide stack, the bloodwork cadence is dictated by those compounds, not by the NAD+.
Stacking Cadence#
NAD+ plays well with basically everything — it's a foundational cofactor, not a signaling molecule competing for receptor space. Standard pairings:
- Oral NR or NMN (250–1000 mg/day) between SC injections to keep the salvage pathway topped up. Oral NAD+ itself is useless; NR at 1000 mg/day roughly doubles whole-blood NAD+.
- TMG 500–1000 mg/day if running high-dose precursors, to offset the methylation draw from nicotinamide clearance.
- Sirtuin activators (pterostilbene or resveratrol 200 mg with fat) — mechanistically complementary, since sirtuin activity is rate-limited by NAD+ availability.
- Longevity stack: NAD+ SC + NMN oral + rapamycin (weekly) + metformin or acarbose is the standard Attia-sphere configuration.
- Post-cycle stack: NAD+ SC + TUDCA 500 mg + NAC 1200 mg handles the hepatocyte NAD+ drain from methylated orals cleanly.
Run it year-round if the goal is longevity maintenance. Pulse it in 4–6 week blocks if the goal is specific recovery work after a hard cycle or training block. Either approach is defensible.
Risks & mistakes
Common (most users)#
- Chest pressure / tightness during IV — the signature "elephant sitting on your chest" sensation. Not cardiac, not dangerous, and entirely infusion-rate dependent. Mitigation: slow the drip. A 500 mg bag over 4+ hours is tolerable; the same bag in 90 minutes is miserable. If it hits mid-infusion, ask the nurse to cut the rate in half — symptoms resolve within minutes.
- Flushing, warmth, mild niacin-like skin response — from partial conversion to nicotinic-acid intermediates. Mitigation: slower infusion, or switch to SC. Pre-loading 500 mg aspirin 30 min before IV helps in susceptible users.
- Nausea and GI cramping (IV) — rate-dependent, resolves at end of infusion. Mitigation: eat a light meal 60–90 min prior, hydrate, slow the rate. Ondansetron 4 mg works if it's persistent.
- Headache, lightheadedness, transient tachycardia — typical during rapid infusion. Mitigation: slower drip, hydration, sit/recline for the session.
- Injection site soreness, bruising, mild local flushing (SC/IM) — NAD+ is acidic enough to sting on SC injection. Mitigation: reconstitute to 100 mg/mL (not more concentrated), inject slowly, rotate abdominal sites, warm the syringe in your hand before injecting. Ice the site for 30 seconds post-injection if stinging is pronounced.
- Next-day fatigue after heavy IV — common after 500–1000 mg loading sessions. Mitigation: don't schedule sessions the night before a heavy training day; treat loading blocks like a recovery week.
Uncommon (dose-dependent or individual)#
- Elevated heart rate / palpitations during infusion — if it persists after slowing the drip, stop the session. Check resting HR and BP on non-infusion days; if you're running AAS with uncontrolled hypertension, fix that first.
- Anxiety / jittery feeling — some users report a stimulant-like edge at high IV doses. Mitigation: drop to SC, lower the single-session dose, move sessions to morning.
- Sleep disruption if dosed late — NAD+ cycles circadianly; pushing it at night can fragment sleep in sensitive users. Mitigation: dose AM or early afternoon.
- Methylation draw with high-dose oral precursor stacking — if you're running NAD+ SC plus 1000 mg NMN/NR daily, nicotinamide methylation can drain SAMe/methyl donors. Not an NAD+ injection problem per se, but a stack problem. Mitigation: TMG 500–1000 mg/day, adequate B12/folate, check homocysteine on annual bloodwork.
- Transient worsening of inflammatory symptoms — eNAMPT is a pro-inflammatory cytokine; in users with autoimmune flares or high baseline CRP, aggressive loading can feel worse before better. Mitigation: back off to 50 mg SC 2×/week and reassess in 4 weeks.
Rare but serious#
- Severe infusion reaction — true allergic-type response (urticaria, bronchospasm, angioedema) is rare but reported anecdotally in clinic settings. Stop immediately, do not rechallenge.
- Syncope during rapid IV — pre-syncope from vasovagal response to the chest pressure sensation. Stop the drip, recline, legs up. Don't try to "push through."
- Sustained tachyarrhythmia — if palpitations continue after the infusion ends, get an ECG. Full stop on further sessions until cleared.
"Plasma concentrations of NAD+ did not rise significantly until approximately 2 hours into the infusion, while downstream metabolites such as methyl-nicotinamide and ADPR were detected much earlier." — Grant et al., Front Aging Neurosci 2019
The practical read on Grant's PK data: the metabolites hit fast, the NAD+ itself climbs slowly, and the chest-pressure/GI symptoms track the early metabolite wave — which is exactly why infusion rate, not total dose, drives tolerability.
Hard contraindications#
- Active malignancy. NAD+ is a substrate for tumor metabolism and PARP-mediated survival; NAMPT inhibitors are being developed as chemotherapeutics. Do not run NAD+ repletion during active cancer treatment without oncologist sign-off.
- Pregnancy and lactation. No human safety data. Avoid.
- Prior severe infusion reaction. Do not rechallenge — the mechanism isn't well characterized and escalation risk is real.
- Strong personal/family history of aggressive cancers — this is a judgment call, not an absolute no, but the CD38/NAMPT/sirtuin axis overlaps with tumor biology enough that cavalier high-dose loading in this population is unwise.
Gender, hormonal, and PCT considerations#
NAD+ is non-hormonal. It does not aromatize, does not bind AR/ER/PR, does not suppress the HPTA, and does not require PCT. Dosing is identical for men and women — no virilization risk, no menstrual effects, no impact on fertility in either direction at standard doses.
Women using NAD+ alongside hormonal contraception or HRT: no known interaction. The only female-specific caution is pregnancy/lactation (above).
For users on AAS: NAD+ is one of the cleaner additions you can run. It doesn't touch lipids, doesn't add to hepatic stress (in fact, helps offset it during methylated oral runs), doesn't affect blood pressure, and layers cleanly with TUDCA, NAC, and telmisartan in a standard on-cycle support stack.
Stack & combine
Multipliers applied when these compounds run together. Values > 1 indicate a bonus on that axis. Tap a partner to expand the mechanism.
| Partner | Type | Lean | Fat loss | Recovery |
|---|---|---|---|---|
| synergistic | ×1.10 | ×1.06 | ×1.22 | |
| synergistic | ×1.13 | ×1.10 | ×1.22 | |
| synergistic | ×1.12 | ×1.17 | ×1.18 | |
| synergistic | ×1.00 | ×1.00 | ×1.17 |
FAQ — NAD+
Where to buy
Swiss Chems
Affiliate link — we may earn a commission at no cost to you.
Real Peptides
Affiliate link — we may earn a commission at no cost to you.
- NAD+Buy NAD+
Research & citations
5 studies cited on this page.
Conclusion
NAD+ is the community's go-to cofactor for mitochondrial recovery, sirtuin activation, and longevity support — but protocol and route make all the difference.
Key takeaways:
- Typical SC dose: 50–100 mg, 2–3× per week; higher doses (250–1000 mg) reserved for slow IV infusions in clinic settings
- Oral NAD+ is useless; use NR or NMN as oral boosters and keep parenteral NAD+ for injection
- Stack with NR/NMN (500–1000 mg/day) and methyl donors (TMG 500–1000 mg) for sustained NAD+ cycling
- Avoid fast IV pushes — infusion rate is everything for tolerability
- Best for recovery, endurance, and cognitive reset; realistic longevity effects hinge on restoring sirtuin and mitochondrial function (Kane & Sinclair, 2018)
- Contraindicated in active cancer, pregnancy, and prior severe infusion reaction
If you're aiming for better recovery, metabolic health, or anti-fatigue resilience, a well-run NAD+ protocol delivers the foundational boost that oral precursors alone rarely match.