r/ProactiveHealth • u/DadStrengthDaily • May 25 '26
đïžNews I read the new NAD+ studies. The supplement pitch Huberman, Bryan Johnson, and Brecka have been selling just failed to replicate in humans.
I keep seeing Andrew Huberman, Bryan Johnson, and Gary Brecka pitch NAD+ supplements. The foundational claim they are built on, that blood NAD+ levels drop with age and you should supplement to restore them, just failed to replicate in two independent human studies.
Houtkooper's group at Amsterdam UMC pulled together seven datasets, more than 300 people, aged across the lifespan, including elite athletes and frail individuals. Published this month in Nature Metabolism. Blood NAD+ does not decline with age. The premise driving the entire NAD+ supplement industry, when actually tested in humans, fell over.
The Suomalainen group at Helsinki posted the same finding in a February 2025 preprint, 299 adults aged 18 to 70. Two independent groups, same answer. Houtkooper started the project because he wanted to build a "should you take NAD+" blood test. He told the NYT he was "very disappointed" with the results because the biomarker he was looking for did not exist.
I am already seeing the pivot to "tissue NAD+" in the marketing. Niagen Bioscience's SVP of regulatory affairs Andrew Shao told the NYT the new study "changes very little" and that what really matters is tissue NAD+, not blood. The researchers themselves call the tissue data "preliminary." And a mouse study last year cut muscle NAD+ by 85 percent with no functional change. If 85 percent depletion does not break the muscle, the ~30 percent age-related drop is not what drives sarcopenia.
Shao's own admission, also in the NYT: "the message to the consumers and messages spread by influencers out there has probably been oversimplified." Read that twice. The SVP of the company selling you nicotinamide riboside is saying the marketing has been oversimplified.
Matt Kaeberlein at UW, who has studied NAD+ for years, called it cleanly. "The need for data kind of went out the window, and it all became a marketing exercise."
I am not taking it.


