top of page
Anti-Aging

NAD+

NAD+ (nicotinamide adenine dinucleotide) is cellular currency used in 500+ reactions — mitochondria spend it to make ATP, PARP enzymes spend it on DNA repair, and sirtuins spend it on inflammation, circadian timing, and maintenance. Whether supplementation feels dramatic depends on how depleted the pool is and how much demand is placed on it. It works best where low NAD+ is part of the bottleneck: post-viral/GLP-1 fatigue, mitochondrial strain, injury recovery, heavy training, alcohol recovery, or age-related decline. For at-home users, IM is the preferred injectable route (50–250 mg, 2–3×/week active; 50–150 mg weekly maintenance); SubQ is acceptable but burns more (split smaller); oral NR/NMN are legitimate daily precursors; IV is clinic-level and tertiary.

Mechanism
Universal cofactor for ATP and sirtuin activity
Clinical Benefits
Restores cellular energy, Supports DNA repair, Enhances mitochondrial function
Typical Dose
Cycle Length
Frequency
Synergistic Compounds
100-250 mg
Ongoing
3-5x / Week
SS-31, MOTS-c, 5-Amino-1MQ, BPC-157, TB-500, GHK-Cu, GLP-1s
At a Glance

At a Glance

Dosage

Active rebuild: 50–250 mg IM, 2–3×/week. Maintenance: 50–150 mg IM weekly. Oral: NR 300–1000 mg/day or NMN 250–500 mg/day.

Protocol

Oral daily for maintenance. Injectable: IM loading 2–12 weeks, then weekly IM or oral. IV is clinic-level loading, not the at-home default.

Results timeline

Subtle energy in week 1 (IV/IM); sleep and cognition build weeks 1–4; sustained metabolic benefits weeks 4–8.

Side effects

IV infused too fast → nausea, chest tightness, flushing, lightheadedness. SC/IM can burn (acidic, charged); IM easier for larger doses, SubQ split smaller if welting.

Regulatory status

Pathway-dependent. NR sold as a dietary supplement (FDA GRAS); NMN status contested in the US; injectable NAD+ lives mostly in compounding/clinic practice.

Best stacked with

SS-31, MOTS-c (Mito Stack); GLP-1 agonists (metabolic support during fat loss); 5-Amino-1MQ (inhibits NNMT); injectable L-Carnitine (fatty-acid transport).


Full Artile

NAD+ became a central longevity molecule because every cell spends it. For severe depletion (post-COVID fatigue, chronic illness, alcohol recovery, high training loads), IV and injectable NAD+ often improve energy, sleep, and clarity faster than oral precursors. For healthy people taking NMN/NR as "longevity insurance," the case is slower and quieter — precursors raise NAD+ pools, but human lifespan-extension evidence is thin. The practical case is strongest where depletion is likely: metabolic support during rapid GLP-1 fat loss, as the redox currency in the Mito Stack with SS-31 and MOTS-c, and for acute recovery after illness or overtraining.


What Is NAD+ and Why It Matters


NAD+ is better understood as cellular currency — a finite resource four systems compete for.

System

What it does

NAD+ cost

Energy production

Carries electrons through mitochondria to make ATP

Constant, ongoing

DNA repair

PARP enzymes consume NAD+ to fix DNA damage

Spikes during stress

Stress response

Sirtuins regulate adaptation/longevity genes

Activity-dependent

Inflammation

CD38 on immune cells breaks down NAD+ for signaling

Accelerates with age

When the pool is full, all four run smoothly; when depleted (chronic stress, poor sleep, illness, aging), the system rations — fatigue, slow recovery, poor stress tolerance, lingering inflammation.


Why NAD+ Declines With Age


By age 60, most people have lost 50–80% of baseline NAD+.

Tissue

Decline

Age range

Plasma NAD+

~80%

20–87 years

Skeletal muscle (NAMPT)

~35%

20–70 years

Liver NAD+

~30%

>60 vs <45 years

Adipose tissue

40–50%

Adult aging

The CD38 / senescent-cell loop is the primary driver: senescent cells accumulate and leak inflammatory signals → macrophages produce 200–300% more CD38 (which breaks down NAD+) → the drain exceeds production → sirtuins (the inflammation brakes) go offline without NAD+ → more inflammation → more destruction. Other drains: chronic DNA damage (PARP overactivation), chronic inflammation, alcohol, viral illness, and sleep disruption. Diet (niacin- and tryptophan-rich foods, trace-NMN foods) supports maintenance but can't restore depleted levels — you'd need ~100 kg of broccoli to equal one 250 mg NMN dose.


Benefits: What the Research Shows


Energy/mitochondria: restored NAD+ raises ATP capacity and mitochondrial efficiency; subjective energy reports inconsistent (Elhassan 2019). Cardiovascular: NR 1000 mg/day reduced systolic BP 5–10 mmHg in older adults and improved vascular function (Martens 2018) — one of the more consistent findings. Metabolic: NMN 250 mg/day improved insulin sensitivity in prediabetic women (Yoshino 2021) — small, needs replication. Cognitive: the NADPARK study showed oral NR raises NAD+ in human brain tissue (MRS), with some Parkinson's improvements. Sleep/circadian: NAD+ oscillates over 24 h via NAMPT; chronic depletion flattens it. Inflammation: NR reduced IL-6 and TNF-α in older adults.

Timeframe

What you might notice

Days 1–7

Subtle energy improvement, especially with IV/IM loading

Weeks 1–4

Sleep quality changes, brain fog lifting

Weeks 4–8

Sustained energy, better exercise recovery

Months 2–3+

Cumulative metabolic and resilience benefits

Long COVID: The Clinical Proof Point


SARS-CoV-2 leaves a persistent NAD+-economy collapse — acute infection activates PARP, upregulates CD38, and diverts the kynurenine pathway, causing sharp depletion. Once NAD+ falls below threshold, the system can't self-recover (inflammation brakes fail, mitochondrial biogenesis stalls, the daily rhythm flattens) — resembling accelerated aging compressed into months. A pilot trial (n=36) of NAD+ patches + low-dose naltrexone showed a 52% responder rate; Jiang 2022 showed NAD+/NMN restored mitochondrial respiration after SARS-CoV-2 suppressed NAMPT/NMNAT.


How to Restore NAD+


Oral precursors (NMN vs NR):

NMN

NR

Conversion path

NMN → NAD+ (via NMNAT)

NR → NMN → NAD+ (extra step)

Typical dose

300–600 mg/day

500–1000 mg/day

Research base

Growing (newer)

Larger (more trials)

Regulatory status

US status evolving

FDA GRAS approved

No head-to-head human trial exists; both raise NAD+ biology, plateauing ~600 mg NMN / 1000 mg NR and at 4–8 weeks. IV: 500–1000 mg over 2–4 h; Grant 2019 showed no plasma rise until >2 h (rapid tissue uptake), peaking +398% at 6 h — essentially a slow-release delivery of nicotinamide/metabolites; clinic-only. IM: 50–250 mg, 2–3×/week active then weekly — the preferred at-home injectable route. SC: 25–100 mg, more sting/welting; split smaller. Formal PK for IM/SC is very limited.

Why NAD+ injections burn

Reconstituted NAD+ is acidic (pH ~3.5–4.0 vs tissue ~7.4), so it stings on contact — peaking within ~30 s, fading over 5–15 min. Higher concentration = more burn (two 50 mg injections sting less than one 100 mg). Some practitioners buffer with pharmaceutical sodium bicarbonate (8.4%) to raise pH (use prescribed materials; buffered NAD+ is less stable). Lowest-pain sites are the love handles and outer thigh; inject slowly, at room temperature, deeper into the fat pad, 27–30g needle, rotating sites. Seek care if pain lasts >30 min, redness spreads, hives/swelling/breathing trouble appear, lumps persist >7 days, or fever develops. IM is the preferred route when SubQ burning is intolerable.

Situation

Best option

Mild fatigue / general optimization

Oral NR or NMN daily

GLP-1 fatigue, mito stack, training strain

IM 50–250 mg, 2–3×/week (active phase)

Significant post-viral / chronic illness

IM loading, or clinic IV loading

Tried oral without effect

Add IM before assuming oral failed

Long-term maintenance

Oral daily, weekly IM, or both

Evidence Assessment


Well-established (human RCTs): precursors raise blood NAD+; NR improves BP in older adults; safe to 2 g/day; NR raises brain NAD+ (NADPARK). Emerging: NMN insulin sensitivity; NAD+ + LDN 52% Long COVID responder rate; improved muscle function; anti-inflammatory effects. Mechanistically sound (unproven in humans): redox support for GLP-1 fat oxidation; CD38 inhibitors (animal only); healthspan extension (mouse). Unknown: multi-year safety (max trial ~12 weeks), whether blood reflects tissue NAD+, optimal precursor, long-term cancer risk.


Safety and Contraindications


Oral NMN/NR: excellent profile to 1–2 g/day (mild GI at high doses). IV: rate-dependent nausea, cramping, chest tightness, lightheadedness (resolve by slowing) — cardiac-history patients should get clearance or start oral. Absolute contraindications: active cancer (NAD+ supports cellular metabolism and may fuel tumor cells), pregnancy/breastfeeding, severe hepatic or renal impairment. Caution: cancer history (consult oncologist), arrhythmias, diabetes on metformin, chemotherapy. The cancer concern is theoretical with no signal in human data, but anyone with active cancer should not supplement.


FAQ

FAQ

What is the recommended NAD+ dosage and protocol?

Route-dependent. Oral NMN 300–600 mg/day (plateau ~600 mg); oral NR 500–1000 mg/day; SubQ 25–100 mg per injection; IM 50–250 mg, 1–3×/week; IV 500–1000 mg over 2–4 h as a 4–5 session loading course. Severe depletion: IV/IM loading for a month, then IM + oral maintenance. Effects build over 2–4 weeks orally, faster with IV.


Does NAD+ need to be cycled?

Oral precursors can be taken continuously (no tolerance buildup). Injectable is typically run in courses: loading then weekly maintenance for 2–3 months, then reassess; some do quarterly IV loading with continuous oral in between.


How long until I feel it?

IV: often within the first week. Oral: builds over 2–4 weeks, plateauing ~6–8 weeks.


Is NMN or NR better?

Both work; NMN is one step closer to NAD+, NR has more published trials. No head-to-head human trial — try one and assess.


How do I know if I have low NAD+?

No routine clinical test. Signs: persistent fatigue despite sleep, slow recovery, brain fog, poor stress tolerance. People over 40, with chronic inflammation, post-viral illness, or high stress are statistically likely depleted.


What supplements help preserve NAD+?

Apigenin and quercetin (inhibit CD38 in cell studies), 5-Amino-1MQ (inhibits NNMT in adipose), resveratrol (activates sirtuins), and reducing chronic inflammation. Human data on CD38 inhibitors is limited.


What's the difference between IV, IM, and SC?

IV delivers into the bloodstream over 2–4 h (clinic, slow infusion); IM injects into muscle (50–250 mg active, 50–150 mg weekly — preferred at-home route); SC injects into fat (25–100 mg, split if welting).


Why do some people feel worse initially?

In high-inflammation or severely depleted individuals, rapid infusion creates metabolic shifts they struggle to handle — start lower and gentler (SC/IM over IV).


Can lifestyle raise NAD+ naturally?

Yes — exercise raises NAMPT 12–30% in muscle, fasting activates salvage, sleep maintains the rhythm, sauna may add ~20%. But these may be insufficient if severely depleted.


Do I need to take NAD+ forever?

Not necessarily — some restore over 3–6 months then maintain with lifestyle; others benefit from ongoing use with chronic conditions or aging.


Related Topics

Related Topics

References

References

  1. Covarrubias AJ et al. NAD+ metabolism and its roles in cellular processes during ageing. Nat Rev Mol Cell Biol 2020. PMC7963035

  2. Camacho-Pereira J et al. CD38 dictates age-related NAD decline and mitochondrial dysfunction. Cell Metab 2016. PMC4911708

  3. Yoshino J et al. NAD+ intermediates: biology and therapeutic potential. Nature Aging 2021. Nature Aging

  4. Brakedal B et al. NR increases brain NAD+ in Parkinson's disease (NADPARK). Nat Commun 2024. Nat Commun

  5. Yoshino M et al. NMN increases muscle insulin sensitivity in prediabetic women. Science 2021. DOI

  6. Martens CR et al. Chronic NR supplementation is well-tolerated and elevates NAD+. Nat Commun 2018. Nat Commun

  7. Grant R et al. Pharmacokinetics of intravenous NAD+ in humans. Redox Biology 2019. PMC6751327

  8. Elhassan YS et al. NR augments the aged human skeletal muscle NAD+ metabolome. Cell Reports 2019. PubMed 31412242

  9. McReynolds MR et al. NAD+ decline is causally linked to loss of metabolic health during aging. GeroScience 2022. PMC8747183

  10. Jiang C et al. NAD+/NMN rescue of SARS-CoV-2-induced metabolic dysfunction. Cell Discovery 2022. Cell Discovery

  11. Covarrubias AJ et al. Senescent cells promote tissue NAD+ decline via CD38+ macrophages. Nat Metab 2020. Nat Metab

  12. de Picciotto NE, Gano LB et al. NMN supplementation reverses vascular dysfunction. Aging Cell 2016. PMID 29514064

  13. Verdin E. NAD+ in aging, metabolism, and neurodegeneration. Science 2015. PMID 24360282

Medical Disclaimer

The content in this protocol guide is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider before beginning any new protocol, supplement, or medication.

bottom of page