[HelloMcFly]

What wouldn't likely be measured with any sort of accuracy is individual variance is gut microbiota, which I'd assume could lead to notable differences. Even so, I think we'd get more signal than noise doing our best to measure and factor out what we are currently able to.

[biomcgary]

Sequencing to identify gut microbiota is now common in research. The general makeup of gut bacteria is relatively stable, so weekly or monthly sampling should be adequate.