Your mitochondria run on NAD+. It's the coenzyme behind every significant energy process in your cells — and by your 50s, you have roughly half as much of it as you did at 20. That decline is not cosmetic. It's measurable, it's tied to nearly every hallmark of biological aging, and it's now something that can be directly addressed.
What Is NAD+?
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme present in every living cell. It exists in two forms — NAD+ (oxidized) and NADH (reduced) — that shuttle electrons through metabolic reactions. Its primary roles include:
- Mitochondrial energy production: NAD+ is an essential electron carrier in the Krebs cycle and oxidative phosphorylation — the biochemical processes that generate ATP, the cell's primary energy currency. Without sufficient NAD+, mitochondria cannot run at full capacity.
- DNA repair: NAD+ is the substrate for PARP enzymes (poly ADP-ribose polymerases), which detect and repair single-strand DNA breaks. Accumulated DNA damage accelerates cellular aging; adequate NAD+ is required for effective repair.
- Sirtuin activation: Sirtuins are a family of proteins (SIRT1–SIRT7) closely associated with longevity biology. They regulate gene expression, stress response, inflammation, and metabolic efficiency. Sirtuins are NAD+-dependent — they cannot function without it.
- Circadian regulation: NAD+ oscillates with the circadian clock and plays a direct role in the CLOCK/BMAL1 feedback loop that regulates sleep-wake cycles, metabolism, and inflammation.
The landmark review by Rajman, Chwalek, and Sinclair in Cell Metabolism (2018) summarized the state of the evidence clearly: NAD+ decline is mechanistically linked to metabolic dysfunction, mitochondrial decay, impaired DNA repair, and the progression of age-related conditions. Replenishment via injectable and oral precursor strategies shows therapeutic potential across multiple systems.
Rajman, Chwalek, Sinclair. "Therapeutic potential of NAD-boosting molecules: the in vivo evidence." Cell Metabolism. 2018;27(3):529–547.
View Cell Metabolism →The NAD+ Decline Problem
NAD+ levels begin declining in early adulthood and accelerate with age. By age 60, most individuals have approximately 50% of the NAD+ they had at 20 — a decline documented in muscle, liver, brain, and skin tissue. This is not a gradual background change; it has measurable functional consequences.
The symptoms patients most commonly associate with NAD+ decline include: persistent fatigue that doesn't resolve with adequate sleep, declining cognitive sharpness and memory retrieval, reduced exercise recovery capacity, slower healing from injury or illness, and a generalized sense that the body's resilience has decreased. These symptoms are nonspecific — they also overlap with thyroid dysfunction, low testosterone, sleep disorders, and other treatable conditions. That's why a functional medicine lab panel before starting NAD+ therapy is the appropriate first step.
What NAD+ Injections Do
Intramuscular NAD+ injection bypasses the digestive tract and delivers NAD+ directly into muscle tissue for rapid cellular uptake. The clinical benefits experienced by patients include:
- Improved cellular energy: More efficient mitochondrial ATP production — the kind of foundational energy that underlies every system in the body, not just a stimulant-style boost.
- Enhanced cognitive clarity: NAD+ supports neuronal function and neurotransmitter synthesis. Many patients describe improved mental sharpness, focus, and recall within 1–2 weeks of a loading series.
- Faster physical recovery: Whether from workouts, injury, or illness, NAD+-supported cells repair damage more efficiently and restore function faster.
- Metabolic improvement: Sirtuin activation influences how the body processes glucose, stores fat, and responds to insulin — effects that build over time with consistent NAD+ supplementation.
- Sleep quality: NAD+'s role in circadian regulation can improve sleep architecture, particularly in patients whose sleep quality has declined alongside other aging-related changes.
Injections vs. IV Drip vs. Oral Supplements
NAD+ IV drip (high dose, 250–1,000 mg): Used in some clinical settings for addiction recovery, neurological support, and aggressive longevity protocols. However, high-dose NAD+ given intravenously causes significant flushing, nausea, chest tightness, and a feeling of racing heart during infusion — requiring very slow administration over two to four hours. The time cost and discomfort make this impractical for most patients.
NAD+ IM injection (100–200 mg): The format Solace uses. Delivers a clinically meaningful dose in 10 to 15 minutes with minimal side effects. The injection site may be slightly sore for a day, but the dramatic IV flush symptoms are avoided entirely. For ongoing supplementation, the IM route is more practical, more comfortable, and produces cumulative benefit over a series of sessions.
Oral NMN or NR supplements: These NAD+ precursors do raise systemic NAD+ levels to a measurable degree. However, the conversion pathway from precursor to active intracellular NAD+ is indirect and dose-limited. Patients who have been taking oral NMN or NR for three or more months without significant symptom improvement typically respond much better to injectable NAD+, which achieves higher tissue concentrations more reliably.
The NAD+ Loading Protocol at Solace
New patients typically begin with a loading series of four to eight IM injections over two to four weeks. This saturates tissue NAD+ levels and is where most patients notice the most significant improvements in energy, clarity, and recovery. Following the loading series, monthly maintenance injections sustain the elevated levels and prevent the return of age-related decline.
Dr. Flávio reviews baseline functional medicine labs before starting — including metabolic markers, mitochondrial function indicators, and a review of symptoms — to ensure NAD+ therapy is appropriate and to track improvements objectively over time.
NAD+ in a Comprehensive Longevity Protocol
For patients approaching wellness from a longevity perspective, NAD+ works best as part of a broader protocol rather than in isolation:
- Peptide therapy (MOTS-C, SS-31) — additional mitochondrial longevity support that complements NAD+ at the cellular level
- IV vitamin therapy — supplies the cofactors and antioxidants that mitochondria need alongside NAD+
- Hormone optimization — testosterone, estradiol, and thyroid hormone all affect mitochondrial function; addressing hormone deficiencies amplifies NAD+ results
- Functional medicine labs — ongoing monitoring to track biological aging markers and adjust the protocol based on objective data
At Solace, Dr. Flávio integrates all of these modalities into personalized protocols. The result is a medical wellness approach that addresses cellular aging systemically rather than treating individual symptoms in isolation.
Frequently Asked Questions
How quickly do NAD+ injections work?
Most patients notice improved energy and cognitive clarity within one to two weeks of starting a loading series — often beginning after the third or fourth injection. The subjective experience varies: some patients describe a noticeable shift in "baseline" energy, while others experience more gradual improvement over the full loading series. The long-term benefits — improved metabolic function, DNA repair efficiency, and cellular resilience — accumulate over months of consistent supplementation and are better reflected in lab markers than in day-to-day perception.
Are NAD+ injections painful?
NAD+ IM injections are a standard intramuscular injection — comparable to a flu shot or vaccine. The injection itself takes seconds, and the site may be slightly sore for 12 to 24 hours afterward. There is no flush, no racing heart, and no nausea — the side effects associated with high-dose NAD+ IV administration. Most patients describe the IM injection as significantly more comfortable than they expected, particularly after hearing about the IV drip experience.
Are oral NMN or NR supplements a substitute?
Not for therapeutic purposes. Oral NMN and NR do raise NAD+ levels — they're a legitimate maintenance tool and better than nothing. But the conversion pathway to intracellular NAD+ is indirect, and published comparisons consistently show higher tissue NAD+ concentrations from injectable forms. For patients who haven't noticed meaningful improvement after three or more months of oral NMN/NR supplementation, switching to injectable NAD+ typically produces noticeably better results. Think of oral supplements as maintenance; injectable NAD+ as therapy.
Who is a good candidate for NAD+ injections?
The best candidates are adults — typically 35 and older — experiencing symptoms consistent with NAD+ decline: progressive fatigue that doesn't resolve with adequate sleep, declining mental clarity and focus, reduced exercise recovery, slower healing, or a general sense that biological resilience has decreased. NAD+ therapy is also appropriate for patients with a longevity focus who want to maintain cellular health proactively, before significant decline has occurred. A functional medicine consultation and baseline labs with Dr. Flávio is the appropriate starting point to confirm the fit.