Right, left, and center, everyone is trying to tell us what THE TRUTH is....
There's one big problem with that, as Obi-Wan Kenobi pointed out -- a lot depends on your point of vantage. THE TRUTH about fats, carbs, supplements, hormones, et al ad nauseum is a highly individual thing in its specifics. All these "authorities" (and I use the term with smirking intention) are very fond of announcing THE truth but in pinning them down there are a lot of caveats; once all of the exceptions are conceded "the code is more what you'd call 'guidelines' than actual rules" ... if you'll forgive me referencing two different movies in one paragraph. ;-)
The "truth" about the benefits/shortcomings of what I eat and supplement with isn't going to be true for anyone else. My genetic strengths and weaknesses, coupled with my infection/damage history are absolutely unique.
One of the pejorative comments these generalizers always toss out is that some of us just think we're "unique snowflakes." Actually, that status is absolutely factual, and not to be unaccounted-for. We may have a large amount in common, but genetic/epigenetic details -- which ARE unique -- are where the rubber hits the road when it comes to determining optimal diet, sleep, exercise, supplementation, lifestyle, and so on.
Even two identical TWINS have epigenetic differences, ferkrisesake. One was dominant in the uterus, one was born first, and each has its own individual post-birth experiences. Did just one turn up with a tick-bite at Scout camp? Was one playing with a healthy child at daycare, while the other played with a child carrying a virus? Did one ingest a food containing a pathogen while the other did not?
So yes, we are unique snowflakes. Yes, some humans are broken. Yes, there is no one truth.
Anyone who says different and claims to be an expert has, ipso facto, demonstrated that he/she is not one.