What Is NAD+? A Plain-English Explanation

The Basics: What is NAD+?

NAD+ stands for Nicotinamide Adenine Dinucleotide. It is a coenzyme present in every living cell in the human body. Despite being rarely mentioned outside scientific literature until recently, NAD+ is involved in hundreds of biological processes that keep you alive and functioning, from converting food into energy to repairing damaged DNA.

Think of NAD+ as a molecular courier that shuttles electrons between reactions in your cells. Without sufficient NAD+, these reactions slow down or fail entirely. Mitochondria, the energy factories inside cells, depend heavily on NAD+ to produce ATP, which is the primary currency of cellular energy. When NAD+ runs low, so does everything powered by ATP: your energy, your focus, your recovery, and your body's ability to repair itself.

NAD+ is also a key substrate for a family of proteins called sirtuins. Sirtuins regulate gene expression, control inflammatory responses, and govern the cellular stress response. Research has linked robust sirtuin activity to extended cellular lifespan and protection against age-related decline. Sirtuins cannot function without adequate NAD+, making NAD+ supplementation a compelling target for longevity-focused medicine.

Why NAD+ Levels Decline With Age

Your body produces NAD+ naturally, primarily from dietary precursors like tryptophan, niacin (vitamin B3), nicotinamide mononucleotide (NMN), and nicotinamide riboside (NR). The problem is that production slows significantly as you age while consumption by the body increases.

Several factors accelerate NAD+ depletion beyond normal aging: chronic stress, poor sleep, a high-sugar diet, alcohol consumption, and environmental toxins all increase the demand on NAD+-dependent repair enzymes called PARPs. When PARP activity is high, triggered by DNA damage, it rapidly consumes available NAD+, leaving less for mitochondrial function and sirtuin activity. This creates a vicious cycle that compounds with age.

What Does NAD+ Therapy Actually Involve?

NAD+ therapy refers to the supervised medical use of NAD+ supplementation in forms that the body can absorb efficiently, going beyond what standard oral supplements can achieve. The most effective delivery methods used by online telemedicine providers today are subcutaneous injection and nasal spray.

The process starts with an online consultation with a licensed physician who reviews your health history and determines if NAD+ therapy is appropriate for you. If approved, you receive a prescription and your therapy kit is shipped directly to your home, usually within 24 to 48 hours.

Who Should Consider NAD+ Therapy?

NAD+ therapy is not a one-size-fits-all solution, but certain groups consistently report meaningful benefits:

Is NAD+ Therapy Safe?

When prescribed and overseen by a licensed physician, NAD+ therapy has a strong safety profile. It has been used clinically for decades in various contexts, and published research has not identified serious adverse effects at therapeutic doses.

The most commonly reported side effects are mild and transient, typically occurring in the first week or two as the body adjusts:

These effects typically resolve within one to two weeks. Physician oversight matters here: a good provider will start you at an appropriate dose and adjust based on your response, rather than issuing a one-size-fits-all protocol.