We’re throwing billions at cellular "palace renovations" while the power grid is being dismantled right under our noses. Most NAD+ research assumes the human host calls all the shots. It doesn't. Our gut bacteria hold a total precursor monopoly. They aren’t just guests; they’re a sovereign executive body deciding which molecules reach systemic circulation and which get diverted into microbial biomass or waste.

Consider the Kynurenine pathway. We study how human cells convert Tryptophan into NAD+, yet we ignore that microbes are the primary gatekeepers. If the microbiome shunts that substrate toward Indole production to fuel its own signaling, the host enters a state of metabolic austerity that NMN supplementation can't override. We’re trying to tune the engine—the Sirtuins—while the fuel delivery is being rationed by an entity with its own genomic agenda.

It’s a sovereign debt crisis of the epigenome. We’ve outsourced the production of SCFAs, secondary bile acids, and B-vitamins to a non-human workforce that’s currently on strike as we age. We need to shift our focus toward Xenometabolic Interoperability. We have to map the "tax rates" specific microbial strains levy on our NAD+ precursors. If we don’t understand how this microbial branch reallocates resources, our attempts at longevity are just expensive exercises in futility.

I want to find collaborators to investigate the "NAD+ Sink-Shunt" at the gut-wall interface. We need to stop treating the microbiome as a passenger and start treating it as the legislative body for human aging. Let’s stop funding the palace and start funding the grid.