The crash is real — and it changes with age
Most of us know the mid-afternoon dip. But many people notice something in their 40s and 50s: the same schedule, the same sleep, and yet the slump arrives earlier and lingers longer. Lifestyle matters, but there's also a cellular side to the story.
Meet NAD+, your cells' energy currency
NAD+ (nicotinamide adenine dinucleotide) is a coenzyme found in every living cell. Its best-known job is helping mitochondria convert the food you eat into ATP — the energy your body actually spends on everything from thinking to walking. No NAD+, no conversion.
The part that declines
Here's the established fact: NAD+ levels fall as we age. Stress, poor sleep, alcohol, and UV exposure appear to accelerate the drain. Lower NAD+ means cells have a harder time producing energy efficiently — one reason scientists connect it to that "running on a smaller battery" feeling.
What researchers are exploring
Whether restoring NAD+ translates into feeling more energetic is still an active area of research — early human studies are promising but not definitive. What is clear: NAD+ sits at the center of how cells make energy, which is why it has become one of the most studied molecules in longevity science.
