I like buttery, vanilla and other sweet smelling perfumes that make me smell like cupcakes. Now I’m reading about cephalic insulin responses and how they break a fast. Do I have to stop wearing these perfumes and wear another type?
Eating cupcakes will break your fast. A short and generally mild (5-10 minute) cephalic insulin spike will not. Also, if this is your normal perfume, you are probably already fairly accustomed to it.
Your question is about as relevant as saying should I steer clear of walking by restaurants, since I like the smell of bacon and I might get a cephalic response…
If you want to smell like a cupcake, have at it!
Let us for a moment entertain the possibility of inhaling your perfume’s scent – or for that matter, as noted already, walking past a bakery on your way to work, or daydreaming about dinner while stuck in a meeting – indeed triggering an insulin secretion, and a significant one at that, capable of halting lipolysis and fatty acid oxidation all across your body, causing the majority of your cells to revert to glycolysis for energy. If that were the case, what would the major consequence be? Well, with access to reserve fatty acids throttled to a crawl, and no new glucose being injected, cells would be forced to rely on what little glucose remained in circulation. Sooner or later you would awake in the ER, with a major hypoglycemic episode behind you and a nurse sternly advising you against perfumed dirty-fasting henceforth.
Thankfully you awoke on reddit instead, either joking or seriously overthinking things. Just in case it’s the latter, I can empathize with the desire for semantic purity, so let’s just put this way: Yes, on some microscopic level your perfume may well be acting as a “fast-breaker”, just as much as air humidity “wets” our clothes every day; but seriously no, your weight loss, autophagy or whatever won’t tangibly suffer as a result.