it boils down to what your goals are and what you want to get out of fasting
if you want to fast and just consume bone broth that is still going to yield tremendous benefits. will it yield AS MUCH benefits as just water fasting? no of course not. but it still will work great for digestive health, immune support, etc.
just do me a favor with the bone broth and this is MANDATORY. make your own and DO NOT add garlic or onions to it otherwise you are fucking it up. you can add salt and herbs only. but no spices! you must MAKE YOUR OWN. the ones you buy from the store are no bueno. as much as I love thomas delauer he does push that kettle bone broth product and i can promise you that it is 100% inferior to making your own!
and when you do the bone broth you must use quality bones. don't buy bones from walmart that came from a sick cow. it has to be organic grassfed cows, or wild fish.