Given how the term xenobiotic is actually used in real life microbiology, using it to describe moderate coffee consumption outs the speaker pretty hard as an expert in nothing more than bro science.
Do the same people argue that other naturally occurring low calorie stimulants like cocaine and ephedrine break the fasted state?
You have to realize that this is a field with a massive amount of pseudoscience penetration in it.
To blindly follow "expert testimony" without reviewing methodology and how people arrive at conclusions is unscientific. It's believing religiously in the expert.
Also, Dr Patrick isn't even 40 and is not considered a "leader in the field" or an "expert on fasting physiology" by any source I've ever seen other than her own commercial for profit website. She has a PhD, and she's working for another Dr on their research team. That's about it.
You also seem quite ignorant of the fact that many things in the scientific community are pretty heavily debated. There is a great deal of disagreement in emerging fields which is a part of why when there is a consensus you know that has been tested to Hell and back.
There is no scientific consensus that zero calorie unsweetened (including non sugar sweeteners like aspartame, xylitol etc) stimulant beverages disturb or break a fasted state.
It's a hypothesis that has not yet been proven. When it's been proven over and over again in research then you can toss it around as if it were a fact.
But right now you're just spreading the unproven hypothetical conjecture of a young PhD still working on their post doc work and pretending that just because she was on a Rogan podcast she's a trusted expert in metabolic physiology.
Furthermore Dr Patrick was asked to provide a source for her claim on twitter and refused to answer the question or provide sources to support her hypothesis.
So, do you know of any data that supports her made up hypothesis? Because she hasn't put any forward.
Fucking A, Alex Jones had more data to support his absurd gay frog claim (the frogs in question were actually observed switching genders due to environmental pollution).