https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7103435/#:~:tex....
You can go down a rabbit hole with the references in this paper - I think a generally interested layperson is definitely capable of understanding papers like this. My instinct is that the hardest to understand papers are often actually so special-area related that those papers don't contain useful information except for researchers. So you can skip them.
Don't know about the second question and suspect no one else does either.
As an aside - how did you manage that transition to stevia? I despise non-sugar sweeteners and can detect them in very small amounts. For "reasons" I don't eat meat and I supplement protein intake with whey. If it wasn't for a small number of high-quality unflavored (and thus lacking artificial sweeteners) whey isolates I would probably re-introduce meat into my diet.