[pakitan]

I see people here mostly talk about effects fasting has on health but not much about effects on mental/physical performance. If you live longer but you're less effective in what you do, fasting turns into a much less attractive choice, at least for some people.

From my very non-scientific experiments, I can tell that my bullet (1 min) chess rating suffers a lot when I'm restricting my calories. It's really hard to measure how fasting would affect a more complex activity, like programming...probably the impact is smaller but there certainly is an impact. With restricted calories, I usually need to add caffeine to the mix to suppress my hunger and make it easier to concentrate.

[dpn]

I tend to be a lot more productive when fasting.

I also tend to be more impulsive, so staying focused on the thing I should be doing, as opposed to what I want to do, is definitely an issue.

That being said, the time I save by not eating breakfast is also nice :)