[exfatloss]

Fellow keto-er here. There is definitely some hidden ultra sugar in some of those restaurant sauces. I've had a similar experience with takeout Chinese that was "just" chicken & vegetables. Two bites and I felt myself catapult out of ketosis, including the sugar rush you describe and even heart palpitations.

Another thing is that some artificial sweeteners instantly kick me out, too. Worse than sugar. I forget which one it is but I grabbed a "sugar-free" energy drink one time. I spit out the very first sip but still got kicked out of ketosis including the heat and sugar rush, that's how strong it was.

That said, stevia and monk fruit are totally fine for me. No effect whatsoever. I slightly prefer the taste of monk fruit.

[barroomhero]

You can just feel yourself go in and out of ketosis? What's that like?

[exfatloss]

Not always, but if it's super drastic. Feels like a massive sugar rush (or maybe it is actually just the sugar rush I'm experiencing when I accidentally eat hidden sugar?)

Get super hot, feel like my blood is rushing, heart beats.. not faster but.. louder?