I have chronic pain, so when I'm not medicating it? I have to make my own (endorphins) which means that the part of my brain responsible for that is in overdrive (4th ventricle), which means it's demanding sugar 24/7 (the brain runs on glucose, and glucose alone).
There are quite a few neural things that -demand- increased sugar intake to feed your brain in order for it to zap about all the messages it wants to send. The brain? Is really good at demanding things. It's very bossy.
We'll call ^^^ that one ^^^ A.
There's also some drug withdrawal effects where that SUGAR! NOW! thing is pretty temporary. Massive, but temporary.
We'll call ^^^ that one ^^^ B.
A = I very deliberately feed my brain very simple sugars throughout the course of the day, typically by drinking it. (Sugar in my coffee, sodas, etc.). I'm almost always drinking *something*. Which keeps my appetite at very normal-esque levels. And then my meals are protein & veg, for the most part. Avg. caloric intake right around 1200 or so per day. When I'm not drinking my sugar? I want to eat every couple hours, and the volume of food in order to GET the sugar my brain wants (NOW!), is easily 5x the calories of drinking it... Or... If I've headed over to junk food? (Dammit! I said NOW! NOW! NOW!) 10x the calories. Been there. Done that. Had to buy new pants. >.> But failing espresso and soda, even just eating a teaspoon of sugar (16 kcal) once an hour, apx. 300 cal per day.
B = Lollipops & Orange juice. Be careful with the orange juice, as there are a few zillion calories per box, and NOW! can very easily = draining the sucker, sloshing your way to the store to buy more, and draining that. But the lollipops are a good trick-your-brain thing (as long as you don't chew them), because it's providing a constant sugar drip, tricking it into not freaking the hell out. (You start to absorb sugar through the membrains of your mouth, unlike most substances, which have to be broken down). When the lollipops don't cut it (crap! Brain caught on!) a shot of OJ will allow lucid thought to return. And then it's back to having a lollipop shoved in your cheek. Once the sugar cravings start subsiding? Lollipops and OJ are a far easier habit to break (toothpaste hates orange juice :wtf: and OJ hates it right back!) by brushing your teeth & sucking on minty mints.
^^^
All of this? Is from when I'm doing well. My diet tends to go sideways // my eating gets pretty disordered when my PTSD kicks in.