This is an odd question. Does the science support that being in ketosis is an all or nothing thing as far as calorie intake? I’m curious if mints at less than 5 calories each will mess me up in the mornings
So the mints could break your fast sooner, but ketosis and calories aren't necessarily linked. Ketosis is all about lack of carbohydrates. I assume they're 1g of carbs each. But there's really no set daily carb amount for remaining in ketosis. It's a person by person thing. Someone that's been doing keto for a while might be able to have 200+ grams of carbs in a day and be back in ketosis the next day. Others might get kicked out with 50g and take days to get back.
I really think one of the main goals of intermittent fasting is to be more aware of your intake, both when and how much. Your question is a perfect example of this. Previously, you might have thought nothing about eating however many of them. But now you are.
If you're on Facebook and want a good group to learn from, check out Ketogenic Intermittent Fasting. It's not a group where people support massive amounts of fat intake in order to lose weight. Why take in fat when you're trying to lose it? It's more protein focused. And read the pinned post first.