NAD+ is a coenzyme found in every living cell. It plays a critical role in converting food into energy, activating sirtuins (longevity proteins), and enabling DNA repair. Without adequate NAD+, your mitochondria produce less ATP — the energy currency of your cells — leaving you fatigued at a fundamental level.
Research from Harvard's David Sinclair lab has shown that declining NAD+ is not just a symptom of ageing but a driver of it. When NAD+ drops, DNA damage accumulates, inflammation increases, and cells lose their ability to function properly.
NAD+ naturally decreases with age due to increased consumption by repair enzymes like PARPs and CD38. Chronic inflammation dramatically accelerates this decline, as does overeating and sedentary behaviour. By 50, most people have roughly half the NAD+ they had at 20.
Alcohol consumption, poor sleep, and chronic stress all further deplete NAD+ reserves. The decline creates a vicious cycle: less NAD+ means worse cellular repair, which means more damage, which consumes even more NAD+.
The two most researched NAD+ precursors are NMN (nicotinamide mononucleotide) and NR (nicotinamide riboside). Human trials show both can raise blood NAD+ levels significantly within weeks. Typical doses range from 250mg to 1000mg daily.
Exercise is the most powerful natural NAD+ booster. High-intensity interval training and resistance exercise both stimulate NAD+ production pathways. Combining regular exercise with time-restricted eating creates a synergistic effect that helps maintain NAD+ levels naturally.
Anyone interested in evidence-based longevity strategies, health optimisation, and understanding the latest research on ageing and healthspan.
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