> Surely you need something beyond water for such a long fast right? You need electrolytes for sure; but unless you've recently been prepping for a body-buildi

> Surely you need something beyond water for such a long fast right? You need electrolytes for sure; but unless you've recently been prepping for a body-building competition, you don't need any calories for quite a bit longer than that. I did a week-long fast for religious purposes many years ago, before the whole IF health craze was a thing. All I had was water, and occasionally some salt. I still had plenty of fat at the end of it, and I wasn't particularly heavy before. According to the book I read at the time (again, focusing on fasting for religious purposes), it's only after 3-4 weeks that a typical person experiences a more urgent type of hunger pang, which is the indicator that your body is starting to cannibalize critical infrastructure (and that it's probably time to stop fasting if you don't want to damage your health). People who are actually overweight presumably have enough calories to last for months. Vitamins and minerals are obviously another thing. You're not going to get a nutrient deficiency in a week, but you might well in a month or two. (I am neither a nutritionist nor a doctor.)