Does NAD+ supplementation slow biological ageing?
NAD+ supplements reliably raise your blood levels. Whether that also slows biological ageing has not yet been demonstrated in people.
NAD+ supplements demonstrably raise NAD+ levels in blood and cells. This has been confirmed repeatedly in people, including at doses of 300 to 900 mg of NMN per day. The effect on blood levels is therefore one of the best-documented results of NAD+ supplementation in people.
But higher blood levels are not the same as slower ageing. When you look at health outcomes that actually matter, such as physical fitness, heart disease, or how you feel, the picture is mixed and often disappointing. One study in 80 healthy middle-aged adults found a modest improvement in walking distance and self-reported health after 60 days of NMN, and a biological age measurement stayed stable while it rose slightly in the group not taking NMN. However, this study was small, lasted only two months, and two of the authors worked for NMN manufacturers. Other studies found little or none of these functional improvements.
Animal studies paint a sunnier picture: mice given NAD+ building blocks showed improvements in metabolism, cellular energy, and lifespan. But the step from mice to people is a large one, and the translation is far from guaranteed.
Whether NAD+ actually declines sharply with ageing in people is less certain than is often suggested. Consistent measurements in human tissue are scarce, which somewhat undermines the reasoning behind supplementation.
In the short term, NMN and NR are safe and well tolerated at doses up to 900 mg per day over several months. Whether long-term use carries risks, such as possible promotion of tumour growth or a build-up of harmful breakdown products, has not been investigated in long-running studies in people. Those risks are therefore neither proven nor ruled out. If you want to try it to improve your physical endurance, one study provides some support for 600 mg of NMN per day for at least 60 days. Keep your expectations modest, though: that evidence rests on a single study with a conflict of interest. For NAD infusions offered by clinics, there is no evidence whatsoever of effectiveness for ageing or health.
This answer draws on several combined overviews and one study with 80 participants. The evidence that NAD+ levels rise is strong and consistent. The evidence that this also leads to health benefits in people is thin and mixed: functional effects are inconsistent or absent in most studies, and the only positive study (Yi 2023) was small, short, and had manufacturers among its authors. Safety and effectiveness studies lasting more than a few months in people are entirely lacking. The researchers themselves repeatedly stress that results from animal studies do not translate straightforwardly to people, and that human data remain scarce.
Does omega-3 slow your biological age?
Omega-3 modestly slows biological ageing on epigenetic clocks. The effect is small, and telomere length does not respond.
Does excess weight accelerate ageing?
Excess weight demonstrably accelerates biological ageing, both through shorter telomeres and through epigenetic clocks. The clearest evidence is already visible in young adults, and losing weight appears to be able to partly reverse the process.
Can nucleotides lower your biological age?
NAD+ supplements measurably raise NAD+ levels in your blood and, in one study, prevented biological age from rising, but did not actively lower it. The evidence is still too thin for firm conclusions, but 600-900 mg of NMN per day appears safe and also improved walking ability in that same study.
Can you really lower your biological age, and does research support this?
There are promising hints that biological age is measurable and perhaps steerable, but this has not been proven. Wait for larger studies in people before basing major decisions on this.
What is NAD+ and why does it decline as you age?
NAD+ measurably declines with ageing, and supplements raise levels demonstrably in people. Whether that also makes you healthier has not yet been proven, and the safety of taking them for many years deserves attention.
At what age does taking NAD+ supplements make sense?
There is no established age at which NAD+ supplementation becomes worthwhile. Studies focus on middle-aged and older adults, but a measurable functional benefit in humans has not yet been demonstrated.