Is crashing the metabolism a real thing? I can’t just fast for 30 days and be alright? Can I have 500 cals a day to avoid any issues? Hunger really isn’t an issue for me and my body fat is high so it’s not like I don’t have energy for my body to pull from, I want to do a 30 day fast
Lot of people are fasting for 14 days+ on this sub. There’s lot of hallabalu about the dangers of extended fasts that I don’t pay much credence to. In my opinion, if you’re maintaining electrolytes, ideally monitored by blood test or regular supplementation of mag, potassium, multivitamin, your body actually has the resources to enter a healthy starvation hunger mode that’s usually triggered by a dearth of food, thanks to hormone regulation and body stores of energy (adipocytes or fat cells, and muscle). What your body needs to survive, is a healthy blood osmolality (using your supplements) and enough water to prevent any third spacing or unequal diffusion across the various fluid compartments. You run into trouble if you’re drinking water without supplementation, as it causes dilution and shoots your kidneys for no reason. Given you have excessive fat stores to spare, the initial insulin drop and glucagon rise should clear your glycogen first before your body looking for other internal sources of energy. Ie, your adipocytes, muscles. Fat is 9kcal/g, protein 4kcal/g.
Fasting doesn’t crash your metabolism nearly as badly as a calorie deficiency does. Metabolism is a very complicated medical subject, but most of the rhetoric and fear about it regarding fasting has been proven inaccurate unless there’s an underlying medical reason for your weight in the first place (ie: thyroid issues). But fasting is way easier on the metabolism than eating less than 1.5k cals is.
If you want to do an extended fast, get a doctor, make sure your electrolytes and health are good, and go for it. The last thing you need to worry about is your metabolism. You got this!