HoldsUp

Charles Brenner

Charles Brenner is a researcher working in the fields of biochemistry and cellular metabolism. His research focuses on NAD+ homeostasis, metabolic regulation, and the physiological effects of nicotinamide riboside supplementation in conditions such as mild cognitive impairment, long-COVID, and cancer survivorship. He also investigates metabolic signaling nodes in cancer, liver disease, and genetic metabolic disorders.

56 claims checked on air: 2 context 2 contradicted 4 overstated 42 supported 6 unverified

What they said on air - contradicted

22 citing their own research

1:01:02contradictedmoderateHow To Boost NAD Levels To Fight Inflammation, Improve Recov

NMN cannot enter cells directly because it has a phosphate group; orally ingested NMN must be converted back to NR before cellular entry.

"NR can get into cells. It can get decorated with the phosphates and converted into its final nucleotide form. NMN can't because NMN already has a phosphate. That phosphate has to be put on inside of cells. So if someone takes if someone is able to find a safe, pure form of NMN... that NMN is being converted back to NR before it gets into cells." (said at 1:01:02)

The speaker claimed that NMN cannot enter cells directly due to its phosphate group and must always be dephosphorylated to NR prior to cellular entry. While extracellular dephosphorylation of NMN to NR via ectoenzymes (such as CD73) represents a recognized metabolic pathway in many tissues, evidence demonstrates that intact NMN can be transported directly into cells. In 2019, research identified Slc12a8 as a specific, sodium-dependent NMN transporter (notably expressed in the small intestine and brain) that transports intact NMN rather than NR. Thus, the categorical assertion that NMN cannot enter cells directly is inaccurate.

1:09:10contradictedmoderateHow To Boost NAD Levels To Fight Inflammation, Improve Recov

In a three-arm trial by McDermott et al., NR improved 6-minute walk test distance in peripheral artery disease patients, while placebo and NR plus resveratrol resulted in degraded walk performance.

"McDermott et al., and I believe that she's the top peripheral artery disease clinical trialist in the country. She's at Northwestern. Did a three-arm clinical trial: placebo versus nicotinamide riboside versus NR plus resveratrol, and found that the NR arm improved their six-minute walk test and the placebo arm as well as the NR plus resveratrol arm degraded their six-minute walk test." (said at 1:09:10)

The claim accurately identifies the three-arm randomized controlled trial in peripheral artery disease (PAD) by McDermott et al. (the NICE trial, PMID 38871717) and correctly states that nicotinamide riboside (NR) alone improved 6-minute walk distance (+7.0 m) while placebo declined (-10.6 m). However, the claim asserts that the NR plus resveratrol arm "degraded their six-minute walk test." In the published trial, NR plus resveratrol also improved 6-minute walk distance (by +26.9 meters relative to placebo among adherent participants), leading the authors to conclude that resveratrol did not add extra benefit to NR alone, rather than causing performance degradation.

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