Can We Slow Down Ageing? The Science of NAD⁺, NMN, and Healthy Longevity

A New Era of Ageing Science 

While ageing used to be seen as a simple fact of life, scientists are now beginning to understand it as something far more complex, and something could be modified or slowed down. 

Current research is focusing on what happens inside our cells over time, from declining energy levels to reduced repair capacity.

At the centre of this process is a molecule gaining global attention: NAD⁺ (nicotinamide adenine dinucleotide). 

What Is NAD⁺ and Why Does It Matter for Ageing? 

NAD⁺ is a molecule found in every cell in your body. It plays a critical role in: 

• Converting food into energy 
• Repairing damaged DNA 
• Supporting healthy cell function 

Scientists often describe NAD⁺ as a “rechargeable battery” that fuels key processes in the body.  

Without enough NAD⁺, cells become less efficient and over time this can contribute to many of the changes we associate with ageing. 

Why NAD⁺ Levels Decline Over Time 

One of the most consistent findings in longevity research is that NAD⁺ levels decline as we age.  

There are several reasons for this, including: 

• Your body produces less NAD⁺ as you get older
• The NAD⁺ you do have is broken down by enzymes more quickly 
• As your cells age they have more damage which requires more NAD⁺ to repair that age-related damage  

This decline can affect multiple systems in the body, including: 

• Energy production 
• Cellular repair 
• Immune response 

Over time, this contributes to fatigue, slower recovery, and increased vulnerability to age-related conditions. 

Sirtuins: The ‘Longevity Proteins’ Powered by NAD⁺ 

NAD⁺ works closely with a group of proteins called sirtuins, often referred to as the body’s “anti-ageing” regulators. 

Sirtuins help to: 

• Repair DNA 
• Protect against cellular stress 
• Maintain metabolic balance in your body

However, they rely on NAD⁺ to function. When NAD⁺ levels drop, sirtuin activity also declines, reducing the body’s natural ability to maintain healthy cells.  

Mitochondria and Energy: The Link to Ageing 

Another key piece of the ageing puzzle lies in the mitochondria, the parts of cells responsible for producing energy. 

As we get older: 

• Mitochondria become less efficient 
• Energy output declines 
• Cellular stress increases  

Because NAD⁺ plays a crucial role in mitochondrial function, its decline is closely linked to reduced energy levels and physical performance over time. 

What Are NMN and NAD⁺ Boosters? 

To counter declining NAD⁺ levels, researchers have explored compounds known as NAD⁺ precursors, including: 

• NMN (nicotinamide mononucleotide) 
• NR (nicotinamide riboside) 

These act as building blocks that the body can use to produce more NAD⁺. 

Do NAD⁺ Boosters Actually Work? 

This is the million dollar question and the answer is nuanced. 

What the science shows: 

• Human studies consistently show that NMN and similar compounds increase NAD⁺ levels in the body 
• Some research suggests potential benefits, including improved exercise capacity, enhanced insulin sensitivity, and better subjective wellbeing 

What remains unclear: 

• Long-term effects are still being studied 
• Not all trials show consistent improvements in health outcomes 
• Individual responses can vary due to genetics and lifestyle  

In other words: NAD⁺ boosters clearly affect biology, but their impact on long-term ageing is still under investigation. 

Natural Ways to Support NAD⁺ Levels 

Interestingly, NAD⁺ isn’t only influenced by supplements. Research suggests lifestyle plays a key role so you can boost your NAD⁺ levels through: 

• Regular physical activity 
• Balanced nutrition 
• Healthy sleep patterns 
• Calorie balance and metabolic health  

These habits support the same systems, including sirtuins and mitochondrial function, that NAD⁺ influences. 

What This Means for Healthy Ageing 

Rather than focusing on “anti-ageing” as a quick fix, scientists are shifting towards the idea of healthy ageing, supporting the body’s natural systems to function as well as possible over time. 

NAD⁺ sits at the heart of this approach because it affects: 

• Energy 
• Cellular repair 
• Stress resilience 
• Metabolic health 

The Bottom Line: NAD⁺ and Longevity 

The growing interest in NAD⁺ reflects a bigger change in how we think about ageing. Ageing is driven by biological processes, not just time and NAD⁺ is a key molecule linking many of these processes.

For now, NAD⁺ isn’t a miracle solution, but it is one of the most promising areas in modern longevity research. 

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2025