Skin aging is not only about visible wrinkles. It starts much deeper, at the cellular level. One of the most critical yet still under-recognized molecules involved in this process is NAD⁺ (nicotinamide adenine dinucleotide)—a central coenzyme essential to life.

With age, NAD⁺ levels naturally decline in humans. This decrease has been causally linked to many age-related conditions and is now recognized as a key driver of biological skin aging, including loss of hydration, uneven tone, inflammation, and reduced firmness.

 

What Is NAD⁺?

NAD⁺ is a coenzyme present in every cell of the human body.
It is involved in the vast majority of metabolic reactions occurring inside our cells.

Without NAD⁺, cells cannot:

• convert nutrients into energy,
• activate cellular repair mechanisms,
• maintain balance when exposed to oxidative or environmental stress.

How Does NAD⁺ Work?

NAD⁺ acts as a cellular conductor, synchronizing the activation of key proteins, including those responsible for:

• DNA repair,
• mitochondrial function,
• antioxidant defense,
• regulation of inflammation.

A Simple Analogy

NAD⁺ can be compared to a firefighter in the body. It transports electrons to neutralize reactions that generate free radicals—just as a firefighter carries water to extinguish fires. Without NAD⁺, cellular damage spreads, much like an uncontrolled fire.

 

The Role of NAD⁺ in Skin Cells

In skin cells, NAD⁺ plays a central role in maintaining resilience and youthfulness. It allows the skin to adapt to chronic environmental stressors, such as:

• UV radiation,
• pollution,
• cigarette smoke,
• oxidative stress.

Key Skin Benefits Supported by NAD⁺

Biological Action	Visible Skin Benefit
DNA repair and cellular regeneration	Smoother skin, reduced wrinkles
Lipid synthesis stimulation	Strengthened skin barrier
Reduction of transepidermal water loss	Improved hydration
Collagen and elastin synthesis	Firmer, plumper skin
Regulation of melanin production	More even skin tone
Immune response modulation	Reduced inflammation and sensitivity

 

Why NAD⁺ Declines with Age

Even with a healthy lifestyle, NAD⁺ levels decline significantly over time.
Between the ages of 50 and 60, NAD⁺ levels can be up to 50% lower than in early adulthood.

This decline is accelerated by:

• UV exposure,
• pollution,
• inflammation,
• repeated cellular damage.

The more stress the skin experiences, the more NAD⁺ is consumed—leading to cellular exhaustion.

 

How the Body Produces NAD⁺

There are three main biosynthesis pathways for NAD⁺:

1. Niacin (Vitamin B3 – nicotinic acid)
   Found in organ meats, tuna, and mackerel.
2. Tryptophan
   An essential amino acid found in legumes, soy, whole rice, and fish.
3. Recycling Pathway (Salvage Pathway)
   Using direct precursors such as NMN and NR, derived from NAD⁺ recycling enzymes.

 

Why Not Supplement NAD⁺ Directly?

NAD⁺ is a large molecule that cannot cross the intestinal barrier intact. It must first be broken down into smaller metabolites.

These metabolites include:

• NMN (nicotinamide mononucleotide),
• NR (nicotinamide riboside),
• NAM (niacinamide).

Importantly, specific transporters for NMN (such as Slc12a8) allow this molecule to enter cells efficiently.

 

Focus on NMN: The Direct Precursor of NAD⁺

NMN is one of the most promising NAD⁺ precursors identified to date.

What Is NMN?

• A naturally occurring molecule found in all forms of life,
• A key intermediate in NAD⁺ biosynthesis,
• A compound capable of crossing the intestinal barrier via specific transporters,
• A direct precursor of NAD⁺ inside cells.

 

NMN vs NR vs Niacinamide: Comparative Overview

Criteria	NMN	NR	Niacinamide (NAM)
Relationship to NAD⁺	Direct precursor	Must first convert into NMN	Indirect precursor
Efficiency in raising NAD⁺	High (short metabolic pathway)	Moderate	Low to moderate
Absorption	Rapid, via specific transporters	Good, conversion required	Very good
Human clinical studies	Tested in human clinical trials	Extensively studied	Widely documented
Positive skin effects	Cellular regeneration, firmness, barrier support	Indirect energy support	Anti-inflammatory, even tone, collagen
Limitations / negative effects	🔹 Clinical research still expanding🔹 Efficacy depends on purity and pharmaceutical grade	🔹 Slower NAD⁺ increase🔹 Possible digestive discomfort at high doses	🔹 May cause skin flushing (redness, warmth), especially at high oral doses🔹 High doses may inhibit sirtuin activity
Tolerance	Good in human trials	Variable	Excellent topically, variable orally
Primary use	Systemic cellular anti-aging	Metabolic support	Dermatology & cosmetics

 

Important Clarification on Flushing

• Flushing is common with niacin (nicotinic acid).
• Niacinamide may also cause flushing when taken orally at high doses.
• NMN and NR are not associated with flushing at studied doses.

 

NMN and Skin Longevity: A New Biological Approach

NMN does not act on the surface alone. It supports a central biological mechanism—the production of NAD⁺—which governs cellular resilience and repair.

Much like collagen precursors stimulate endogenous collagen production, NMN supports the body’s natural capacity to maintain youthful skin function.

 

Conclusion

Understanding NAD⁺ means understanding skin aging at its source.
NMN represents a new generation of longevity-inspired actives—working with the biology of the skin, not against it.

Less correction.
More cellular intelligence.