Ever since I started fasting, I consistently feel cold throughout the day. I used to be a warm body type of person. Recently I find myself turning on the heater a lot in my car lately. Has anyone experienced this or can anyone provide information.
First year med student best guess: A lot of processes are regulated by the amount of glucose you have floating around in your blood. A lack of glucose, like in the fasted state, turns off/on certain processes in the body. One of these processes is the release of epinephrine, which can act to limit blood flow. (This is the same reason your hands get clammy when you’re nervous.)
So fasting = increased epinephrine = decreased blood flow = cold.
Also probably a MILLION other things because, you know, biology.
Bathroom break and no time to google for a reference, but in short I had this for a couple years dieting, keto, and now fasting. I found out only recently that your body actively lowers your core temp in preparation for fat burning which generates heat. Personally I constantly go back and forth between being cold and hot when the temp in the room is constant.
I’m sure there’s science behind it, but I’ve also experienced this. Before, I couldn’t stand to not have a fan on in my office and I’d always remove my jacket the second I walked it, now I’ve noticed I don’t do that anymore, but the temperature remains the same.