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NAD+

LongevityResearch-Grade

Last reviewed: May 24, 2026

Also Known As: Nicotinamide Adenine Dinucleotide, NAD, NADH (reduced form), Coenzyme 1

Peptide Class: Dinucleotide Cofactor (NOT a peptide) — Sirtuin Substrate / Mitochondrial Cofactor

Regulatory Status: Not FDA-approved as injectable therapy. Oral precursors (NMN, NR) sold as dietary supplements. IV offered in clinical settings. Not WADA-prohibited.

What is NAD+?

NAD+ (nicotinamide adenine dinucleotide) is a coenzyme present in every cell of every living organism. It plays a central role in cellular metabolism, energy production, DNA repair, and gene expression regulation. Unlike most peptides on Prof. Peptide, NAD+ is technically a small-molecule cofactor rather than a peptide — but it's included because it's commonly stacked with peptides in longevity protocols and sold by the same vendors. NAD+ levels decline ~50% from age 20 to 60, and this decline is implicated in many hallmarks of aging including mitochondrial dysfunction, accumulated DNA damage, and reduced sirtuin activity. NAD+ supplementation has emerged as one of the most researched longevity interventions of the past decade. Often paired with Epitalon for combined cellular metabolism + telomere maintenance. New to peptide research? Start with the basics →

Reported benefits:

  • Restoration of cellular NAD+ levels to youthful range
  • Sirtuin enzyme activation (SIRT1, SIRT3, SIRT6) — longevity gene activation
  • Enhanced mitochondrial function and ATP production
  • Improved DNA repair via PARP activation
  • Cognitive support and neuroprotection
  • Combined energy + recovery + longevity effects

Common research dose: Subcutaneous injection: 50–100 mg once or twice weekly. IV infusion (clinical settings): 250–1000 mg over 2–4 hours. Oral precursors (NMN, NR): 250–1000 mg daily. Sublingual NAD+: 50–125 mg daily.

Where to buy: PP maintains a vetted list of peptide vendors with verified discount codes. See Verified Discount Codes → for current options.

How does NAD+ work?

NAD+ is required for hundreds of enzymatic reactions including the citric acid cycle, electron transport chain, and beta-oxidation — ATP production fundamentally depends on adequate NAD+ levels. It's also the obligate substrate for sirtuin enzymes (the 'longevity gene' pathway) and PARPs (DNA damage repair). The age-related NAD+ decline is driven largely by CD38, an NAD-degrading enzyme that increases with aging and chronic inflammation — supplementation overcomes this consumption.

  1. Cofactor for Cellular Metabolism [1]. NAD+ is required for hundreds of enzymatic reactions including the citric acid cycle, electron transport chain, and beta-oxidation. ATP production fundamentally depends on adequate NAD+ levels.
  2. Sirtuin Activation [2]. NAD+ is the obligate substrate for sirtuin enzymes (SIRT1–7). Sirtuins regulate gene expression, DNA repair, mitochondrial biogenesis, and cellular senescence — collectively the "longevity gene" pathway.
  3. PARP Activation [3]. Poly-ADP-ribose polymerases use NAD+ for DNA damage repair. Adequate NAD+ supports genome integrity, particularly under oxidative stress.
  4. CD38 Substrate [4]. CD38, an NAD-degrading enzyme, increases with aging and chronic inflammation. This drives the age-related NAD+ decline. NAD+ supplementation overcomes the consumption.
  5. Mitochondrial Biogenesis. Adequate NAD+ supports PGC-1α activation and mitochondrial biogenesis. Critical for muscle, brain, and metabolic tissue function.

What is NAD+ used for?

NAD+'s research evidence base spans aging and longevity (the central application — most-studied longevity intervention of the past decade), cognitive function and neuroprotection, cellular repair, metabolic syndrome, and recovery/athletic performance. Human clinical trials have grown substantially since 2018 (NR-Martens), 2022 (NMN-Igarashi), and 2023 (NR-Orr), though the 2024 meta-analysis tempers some clinical efficacy claims — NAD+ elevation is consistent, downstream functional benefits need more data.

  1. Aging & Longevity [5]. NAD+ decline is a hallmark of aging. Restoration in animal models extends healthspan, reduces age-related cognitive decline, and improves muscle function. Most-studied longevity intervention of the past decade.
  2. Cognitive Function & Neuroprotection. NAD+ supports neuronal energy metabolism and mitochondrial health. Studies in cognitive decline, Parkinson's disease, and post-traumatic brain injury.
  3. Cellular Repair. DNA repair via PARP, mitochondrial repair via sirtuins. Critical in oxidative stress contexts.
  4. Metabolic Syndrome. NAD+ supports metabolic flexibility, insulin sensitivity, and lipid metabolism. Research interest in obesity and Type 2 diabetes — though 2024 meta-analysis found most metabolic markers (glucose, lipids) not significantly different from placebo despite NAD+ elevation.
  5. Recovery & Athletic Performance. Anecdotal community use for post-workout recovery, jet lag, and energy. Limited controlled athlete data.

How long does NAD+ take to work?

NAD+ effects develop on multiple timescales. Acute energy/recovery effects within hours of injection. Cognitive effects: 1–2 weeks of consistent use. Long-term anti-aging effects: months. Most users assess benefit after 4–8 week protocols. Subjective improvements in energy and recovery often appear before measurable changes.

Acute energy and recovery effects appear within hours of injection. Subjective cognitive effects develop over 1–2 weeks of consistent use. Long-term anti-aging effects accumulate over months — sirtuin activation and DNA repair are not acute pharmacology but cumulative cellular processes. Most users assess benefit after 4–8 week protocols. Subjective improvements in energy and recovery often appear before measurable changes in biomarkers like blood NAD+ levels.

How is NAD+ dosed?

NAD+ dosing varies dramatically by route of administration. Subcutaneous and IV produce direct NAD+ elevation; oral precursors (NMN, NR) require conversion in the body. Subcutaneous is notoriously painful (burning at injection site for several minutes). IV infusion is clinical-setting only. Sublingual and oral precursors avoid injection but with different absorption profiles.

  1. Subcutaneous injection. 50–100 mg once or twice weekly.
  2. IV infusion (clinical). 250–1000 mg over 2–4 hours, monthly to weekly.
  3. Sublingual. 50–125 mg daily.
  4. Oral NMN/NR (precursors). 250–1000 mg daily — different absorption profile, less direct.
  5. Cycle length. Continuous protocols common. Some users cycle 3 months on / 1 month off.
  6. Time of day. Morning preferred (some users report sleep disruption with evening dosing).

Subcutaneous NAD+ is notoriously painful at the injection site — slow injection over 30–60 seconds reduces burning. IV infusion is more tolerable but requires a clinical setting. Oral precursors (NMN, NR) avoid the injection burning.

Need to calculate your dose? Convert mg to syringe units and plan reconstitution with the dosage calculator →.

How is NAD+ administered?

NAD+ is administered through multiple routes: subcutaneous injection (most painful but accessible), IV infusion (clinical-setting, most tolerable), sublingual (moderate absorption), or oral precursors NMN/NR (avoids injection but indirect). The route choice has the biggest impact on tolerability and convenience — many users start oral and move to clinical IV if they want stronger effects. For the practical mechanics of subcutaneous injection technique, see the syringes and injection technique guide.

  1. Subcutaneous route. Site rotation between abdomen, thigh, upper arm. Slow injection over 30–60 seconds significantly reduces burning sensation.
  2. IV infusion. Clinical setting only. 2–4 hour infusion under physician supervision.
  3. Sublingual. Hold under tongue for 60 seconds before swallowing for absorption through oral mucosa.
  4. Oral precursors. NMN or NR capsules with or without food.
  5. Time of day. Morning preferred to avoid sleep disruption — many users report stimulant-like effects.
  6. Reconstitution. Bacteriostatic water, swirl gently — do not shake. Light-sensitive — degrades quickly in sunlight.

Timing context. NAD+'s biological effects accumulate via gene expression (sirtuin activation), DNA repair (PARP), and mitochondrial biogenesis rather than acute pharmacology. The route choice affects tolerability more than timing. Subcutaneous and IV produce direct NAD+ elevation; oral precursors require multi-step conversion to active NAD+, with absorption affected by gut metabolism and aging-related conversion-pathway decline.

AspectRecommendation
FrequencySC: 1–2× weekly. IV: monthly to weekly. Oral: daily.
Best time of dayMorning preferred — some users report stimulant-like effects that disrupt sleep if dosed late
FoodNo fasting required for any route
Route choiceOral NMN/NR for entry-level (no injection); SC for direct NAD+ (painful); IV for max bioavailability (clinical setting)
Half-lifeShort plasma half-life; cellular NAD+ pools persist via downstream conversion
Steady-stateBlood NAD+ levels rise measurably within days; downstream functional effects accumulate over weeks-months

Reconstitution math. Choose your bacteriostatic water volume based on dose precision. NAD+ research vials are typically 500 mg — significantly larger than peptide vials. Because per-dose amounts are large (50–100 mg subcutaneous, up to 250 mg sublingual equivalent), 1–2 mL reconstitution keeps draws within insulin syringe capacity. All units below are measured on a U-100 insulin syringe (100 units = 1 mL). The table assumes a 500 mg vial.

BAC waterConcentration25 mg dose50 mg dose100 mg dose250 mg dose
1 mL500 mg/mL5 units10 units20 units50 units
2 mL250 mg/mL10 units20 units40 units100 units
5 mL100 mg/mL25 units50 units100 unitsn/a*

*Draw exceeds standard 100-unit insulin syringe capacity at this reconstitution volume — would require split injections or a lower reconstitution volume.

Units vs mcg. At a 500 mg vial, each unit drawn delivers 5 mg of NAD+ at 1 mL reconstitution, 2.5 mg at 2 mL, and 1 mg at 5 mL — the reconstitution volume determines the mg-per-unit conversion. For a primer on reading insulin syringes and choosing the right barrel size, see our guide on syringes and injection technique.

What does NAD+ stack well with?

NAD+'s canonical pairing is with Epitalon (cellular metabolism + telomere maintenance — two non-overlapping aging hallmarks). NMN or NR oral precursors are sometimes combined with injectable NAD+ for sustained levels. Resveratrol pairs mechanically (sirtuin activator). Methyl donors (TMG, B12) counter NAD+ methylation depletion at high doses.

  1. Epitalon. Epitalon is the most common longevity stack pairing (cellular metabolism + telomere maintenance). See the Epitalon vs NAD+ comparison for protocol differences.
  2. NMN or NR oral precursors. Sometimes combined with injectable NAD+ for sustained levels between injections.
  3. Resveratrol. Sirtuin activator that pairs mechanically with NAD+ — sirtuins require NAD+ as substrate, and resveratrol activates SIRT1.
  4. CoQ10 + MOTS-c. Mitochondrial support pairing. MOTS-c activates AMPK through a non-overlapping pathway.
  5. GHK-Cu. GHK-Cu for combined gene expression modulation + NAD+ metabolism. Common longevity pairing.
  6. Methyl donors (TMG, B12). Counter NAD+ methylation depletion at high doses — particularly relevant for chronic high-dose protocols.

What are the side effects of NAD+?

Subcutaneous NAD+ is notoriously painful at the injection site (burning sensation lasting several minutes — major reason many users start with oral precursors). IV infusion is more tolerable but requires a clinical setting. Most-reported user effects are flushing (most common with IV/SC), mild nausea, and transient warmth. Methylation depletion at very high doses is real but counterable with methyl donors. Cancer patients should consult their oncologist.

Common (most users)

  1. Flushing. Most common with IV/SC routes.
  2. Mild nausea. Common with rapid administration.
  3. Transient warmth sensation. Often paired with flushing.
  4. Injection site pain/burning. Notable with subcutaneous — the primary tolerability issue.

Less common (moderate)

  1. Mild headache. Inconsistent across users.
  2. Brief anxiety or restlessness. During IV infusion (slow the drip).

Serious (rare)

  1. No major adverse events at therapeutic doses.
  2. Very rare allergic reactions.
  3. Methylation depletion at very high doses. Counter with methyl donors (TMG, B12).

Subcutaneous NAD+ is notoriously painful at the injection site. IV infusion is more tolerable but requires a clinical setting. Oral precursors (NMN, NR) avoid the injection burning entirely. The pain at the injection site is a major reason many users start with oral precursors.

Does NAD+ interact with other drugs?

NAD+ has limited documented drug interactions at therapeutic doses. Theoretical concern with methotrexate (folate metabolism). Cancer therapies have complex interactions — NAD+ supports both healthy and theoretically cancer cells; oncology consultation recommended. SSRIs have no documented interactions. Most other supplements and medications are generally compatible.

  1. Methotrexate. Theoretical concern; NAD+ may affect folate metabolism.
  2. Cancer therapies. Complex interaction. NAD+ supports both healthy cells AND theoretically cancer cells. Cancer patients should consult oncologist.
  3. SSRIs. No documented interactions.
  4. Most other supplements and medications. Generally compatible.

How should NAD+ be stored?

  1. Lyophilized: -20°C long-term, 2–8°C short-term.
  2. Reconstituted: 2–8°C, use within 14 days.
  3. Light-sensitive — degrades quickly in sunlight.
  4. Do NOT freeze reconstituted solution.
  5. Reconstitute with bacteriostatic water for injection. Swirl gently — do not shake.
  6. Discard if cloudy, discolored, or contains particles.

What are the limitations of NAD+ research?

NAD+ is NOT FDA-approved as an injectable therapy. Oral precursors (NMN, NR) are sold as dietary supplements but the FDA has issued warnings to some manufacturers. Most clinical evidence for longevity claims comes from animal models — the 2024 meta-analysis found NMN consistently raises blood NAD+ but most clinically relevant outcomes (fasting glucose, triglycerides, cholesterol) were not significantly different from placebo. NAD+ is technically a dinucleotide cofactor, not a peptide. NOT on the WADA prohibited list.

NAD+ is NOT FDA-approved as an injectable therapy. Oral precursors (NMN, NR) are sold as dietary supplements in the US but the FDA has issued warnings to some manufacturers. NAD+ IV infusion is offered in clinical settings (functional medicine clinics) under physician supervision.

Most clinical evidence for longevity claims comes from animal models. Human clinical trials are growing but still limited compared to the marketing volume around NAD+ products. The 2024 NMN meta-analysis tempered some clinical efficacy claims — NAD+ elevation is consistent, downstream functional benefits in humans need more data.

Research-grade material is sold by specialty peptide/longevity vendors. Quality varies; verify Certificate of Analysis. Subcutaneous injection burning is commonly reported and should be expected.

Anti-doping: NAD+ is NOT currently on the WADA prohibited list. Some athletic federations may have stricter rules.

The “is NAD+ a peptide” question — technically NAD+ is a dinucleotide cofactor, not a peptide. It's included on Prof. Peptide because of its prevalence in longevity stacks alongside peptide therapies and its sale by the same specialty vendors.

Where to source NAD+

Subcutaneous and oral research-grade NAD+ is sold by specialty peptide and longevity vendors. IV infusion is offered in functional medicine clinics. Quality varies — verify Certificate of Analysis. The vendors highlighted below have been vetted for transparent third-party testing, traceable batch documentation, and verified discount codes.

Vital Core Research20% off

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Spartan Peptides10% off

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Apollo Peptide Sciences10% off

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See all 17 verified vendors →

NAD+ FAQ

Is NAD+ a peptide?

Technically no. NAD+ is a dinucleotide cofactor — not a peptide. It's included on Prof. Peptide because it's commonly stacked with peptide therapies in longevity protocols, sold by the same specialty vendors, and serves as the cofactor for the same sirtuin and PARP pathways targeted by other anti-aging interventions.

Is NAD+ FDA-approved?

NAD+ is NOT FDA-approved as an injectable therapy. Oral precursors (NMN, NR) are sold as dietary supplements in the US, though the FDA has issued warnings to some manufacturers. NAD+ IV infusion is offered in clinical settings (functional medicine clinics) under physician supervision. Subcutaneous and oral research-grade NAD+ is sold by specialty vendors.

NAD+ vs NMN vs NR — which is best?

Different positions in the same metabolic pathway. NAD+ is the active cofactor itself; NMN (nicotinamide mononucleotide) and NR (nicotinamide riboside) are precursors the body converts to NAD+. Direct NAD+ injection is most bioavailable but most painful (subcutaneous burning) and most controversial. Oral NMN and NR avoid injection but require the body to convert them. Most longevity research focuses on NMN and NR for practical reasons; clinical settings use IV NAD+.

Does subcutaneous NAD+ really burn that much?

Yes. Subcutaneous NAD+ injection is notoriously painful at the injection site — burning sensation that can last several minutes. Slow injection over 30–60 seconds and site rotation help reduce this. IV infusion (clinical setting) is more tolerable; oral precursors (NMN, NR) avoid the issue entirely. Many users start oral, then move to clinical IV if they want stronger effects.

How is NAD+ different from B vitamins?

NAD+ is synthesized in the body from niacin (vitamin B3) and other precursors. Niacin supplementation increases NAD+ levels through this conversion pathway, which is part of why niacin has been used historically for aging-related applications. The advantage of direct NAD+ or NMN/NR over niacin is bypassing some of the conversion steps that decline with age, particularly the ones limited by CD38 enzyme activity in older adults.

Can NAD+ help with cognitive decline?

Animal models show NAD+ supports neuronal energy metabolism and mitochondrial health. Studies in cognitive decline, Parkinson's disease, and post-traumatic brain injury are early-stage but promising. Human clinical trials are limited compared to the marketing volume around NAD+ products. Some users report subjective cognitive benefits within 1–2 weeks, but controlled efficacy data is thinner than the marketing implies.

Is it safe to take NAD+ long-term?

Short-term safety is excellent at therapeutic doses. Long-term human safety data is growing but still limited compared to decades of clinical use peptides like Thymosin Alpha-1. Most longevity protocols cycle 3 months on / 1 month off. At very high doses, methylation depletion can occur — methyl donors (TMG, B12) are sometimes added to counter this. Cancer patients should consult their oncologist; NAD+ supports both healthy AND theoretically cancer cells.

How does NAD+ compare to Epitalon for longevity?

Both are foundational longevity research compounds with different mechanisms. NAD+ restores cellular metabolism cofactor levels and sirtuin activity (energy + cellular repair). Epitalon activates telomerase (chromosome end maintenance + pineal melatonin restoration). The two are commonly stacked together because they target non-overlapping aging hallmarks. See the Epitalon vs NAD+ comparison for a side-by-side breakdown.

Where can I buy NAD+?

Subcutaneous and oral research-grade NAD+ is sold by specialty peptide and longevity vendors. IV infusion is offered in functional medicine clinics. Quality varies; verify Certificate of Analysis. PP maintains a list of vetted vendors with verified discount codes — see Verified Discount Codes →.

References

  1. Verdin E. NAD+ in aging, metabolism, and neurodegeneration. Science. 2015;350(6265):1208-13.
  2. Imai S, Guarente L. NAD+ and sirtuins in aging and disease. Trends Cell Biol. 2014;24(8):464-71.
  3. Cantó C, Menzies KJ, Auwerx J. NAD+ Metabolism and the Control of Energy Homeostasis: A Balancing Act between Mitochondria and the Nucleus. Cell Metab. 2015;22(1):31-53.
  4. Camacho-Pereira J, Tarragó MG, Chini CCS, et al. CD38 Dictates Age-Related NAD Decline and Mitochondrial Dysfunction through an SIRT3-Dependent Mechanism. Cell Metab. 2016;23(6):1127-1139. https://pmc.ncbi.nlm.nih.gov/articles/PMC4911708/
  5. Yoshino J, Baur JA, Imai SI. NAD+ Intermediates: The Biology and Therapeutic Potential of NMN and NR. Cell Metab. 2018;27(3):513-528.
  6. Wikipedia. Nicotinamide adenine dinucleotide. https://en.wikipedia.org/wiki/Nicotinamide_adenine_dinucleotide

Published Studies

Plain-English summaries of the peer-reviewed studies behind the claims above. Click any title to read the source paper.

Nature Communications / PubMed · 2018Open Access
Chronic Nicotinamide Riboside Supplementation Is Well-Tolerated and Elevates NAD+ in Healthy Middle-Aged and Older Adults →

Martens CR, Denman BA, Mazzo MR, et al.

The landmark human trial establishing that oral NR supplementation safely and effectively raises NAD+ levels in middle-aged and older adults. In this 2×6-week randomized, double-blind, placebo-controlled crossover trial, NR supplementation significantly increased whole blood NAD+ metabolism without adverse effects. The study also found initial signals of benefit for blood pressure and arterial stiffness — suggesting NAD+ restoration may have downstream vascular benefits beyond metabolic function.

NPJ Aging / PMC · 2022Open Access
Chronic Nicotinamide Mononucleotide Supplementation Elevates Blood NAD+ Levels and Alters Muscle Function in Healthy Older Men →

Igarashi M, Miura M, Williams E, et al.

A randomized, double-blind, placebo-controlled trial of 250mg daily NMN supplementation in healthy older men over 6–12 weeks. NMN significantly elevated whole blood NAD+ and NAD+ metabolite concentrations, with nominally significant improvements in gait speed and left grip strength.

GeroScience / PMC · 2023Open Access
A Randomized Placebo-Controlled Trial of Nicotinamide Riboside in Older Adults with Mild Cognitive Impairment →

Orr ME, Garber G, Ramsay MT, et al.

A pilot RCT examining NR's effects on cognition in 20 older adults with mild cognitive impairment. NR at 1g/day raised blood NAD+ and reduced epigenetic age as measured by PhenoAge and GrimAge clocks. Cognitive test scores did not significantly improve over 10 weeks — likely due to small sample size and short duration.

Journal of Nutritional Biochemistry / PubMed · 2023Paywalled
The Safety and Anti-Aging Effects of Nicotinamide Mononucleotide in Human Clinical Trials — An Update →

PubMed Research Group

A review summarizing the growing human clinical trial pipeline for NMN. The paper documents how NAD+ levels decline with aging and explains why restoration is theoretically significant — NAD+ is an essential substrate for sirtuins, PARPs, and hundreds of redox reactions governing mitochondrial function.

Diabetes & Metabolic Syndrome / PubMed · 2024Paywalled
Efficacy of Oral NMN Supplementation on Glucose and Lipid Metabolism — A Systematic Review with Meta-Analysis →

PubMed Research Group

A 2024 meta-analysis of 12 RCTs (513 participants) examining NMN's effects on metabolic health markers. The analysis confirmed NMN consistently and significantly elevates blood NAD+ levels, but found most clinically relevant outcomes (fasting glucose, triglycerides, cholesterol) were not significantly different from placebo. An important counterbalance to enthusiastic popular coverage.

LongevityCellular MetabolismSirtuin ActivatorResearch-Grade

Related Peptides

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Comparisons

Epitalon vs NAD+ →

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For educational and research purposes only. Not medical advice. Not for human use.