[d1zzy]

Hmm, this seems dangerous or maybe unique to each individual.

In the past I've had low blood sugar issues (started shaking and got splitting headache) because I forgot to eat for 24h or so and worked long hours, it wasn't a nice experience and I most certainly wouldn't want to repeat that on purpose by fasting. In addition to that, I often "bonk" on longer bike rides (don't eat sufficiently) and do intensive cardio exercise 6 hours a week. I have a BMI around 22 (used to be lower but hey, I'm not getting any younger..).

So do you think this is something anyone can/should engage in? How do you decide if your body can safely engage in multiday fasting like that?

[bitL]

I don't know frankly. I was surprised it was so easy for me, but let's say first day I get headaches which I attribute to caffeine/sugar withdrawal, maybe that's your case as well. Drinking 1 liter of water quickly often resolves that though. It's possible you are actually dehydrated as most water comes from food and not drinks, so if you continue drinking like you are used to, you end up with insufficient water.

[sizzle]

Just drinking water can lead to electrolyte imbalance or is am I mistaken?

[bitL]

You are completely right. If you scroll up 3 posts you'll see I mentioned "electrolytes-only".