Hacker News Reader

Comment by Zaak | Hacker News Reader

Fasting is a periodic religious observance for me. The main effect I have noticed is increased irritability, but then I've never done cognitive tests while fasting.

View on HN

That might be from the caffeine withdrawals. I'm trying it wihtout caffeine at all this year, and it's been great.

Espresso has no calories

Grandparent is talking about religious fasting, not a diet. It's likely not about calories.

Indeed. It's abstaining from all food and drink for a goal of 24 hours. I generally manage about 12, but it's something I'm working on improving.

Do note that almost everyone else only abstains from food, but does drink a lot of water (often with electrolytes). It makes a huge difference, irritability and otherwise.

That's good to know. Fasting for me is partly an exercise in choosing to do something that's uncomfortable for my body to achieve a higher purpose. It is explicitly not supposed to be damaging or unhealthy in any way (people who are sick etc are discouraged from fasting). I will look into staying hydrated while abstaining from food.

I'm trying it with caffeine pills; also great!

Or, a carb-heavy diet. When I fast while doing keto, it's almost not noticeable, and I'll often just forget to eat and suddenly realize I haven't eaten in a day or more. If I've cheated on carbs and try to jump back into fasting, I'm ready to commit murder after 10 hours.

Thanks for the info. I tend to have a carb-heavy diet. I wonder if doing a low-carb diet for a couple days before fasting would help. Or do you think it would take longer than that to acclimate?

Some people might just be built differently.

Take me, for example. Ever since I was a teen I have fasted until midday most days (for lack of time) and it significantly affects my cognition. I start feeling irritable at about 10am and unable to concentrate because of feelings of hunger, stomach grumbling, and slight shakiness.

I am a teacher now, and I can tell how my cognition is doing every morning depending on my performance in the classroom. I find that I often mumble and screw up my grammar while lecturing if I haven't had breakfast. I am not calm, but I would not say I feel "energized." I am clearly anxious. My anxiety gradually increases until I have lunch. Then I feel calm and with the ability to think.

It might be genetic. My grandmother was known to be unable to function without breakfast. My mother was the same way.

Reply on news.ycombinator.com