Gwyneth Paltrow has tried it. So have Kendall Jenner and Hailey Bieber. …
Nicotinamide adenine dinucleotide, or N.A.D.+, has been among the hottest anti-aging supplements for several years. …
The molecule is critical for cellular metabolism and other fundamental biological processes, and scientists and supplement companies alike have asserted that its levels drop with age. The idea that taking an N.A.D.+ supplement could help with healthy aging took off, despite the fact that evidence showing a benefit in humans is slim.
And new research suggests that part of the thinking that helped to fuel the booming market for these supplements may be wrong. A study published this month in Nature Metabolism showed that blood levels of N.A.D.+ don’t actually fall with age. …
“It did sort of become dogma that N.A.D.+ levels decline with age universally and that that’s contributing to age-related functional declines,” said Matt Kaeberlein, an affiliate professor at the University of Washington who has studied N.A.D.+ but was not involved in the new research. “This should cause people to question how much of that is reality.”





















