How does one's cognitive competences fare during the fasting day, Virgin? Is your ability to 'think' at all hindered, akin to transitioning to keto or some such?
No not at all....I go to school and I work full-time at a dotcom and I like to think i do pretty well at both. Once my blood-sugar stabilizes, about 12-16 hours after my last meal, I don't feel hungry and I think more clearly than I can after eating.
That being said, I do recall having some difficulties for the first month or so. A lot of it was mental, thinking that I was losing muscle, etc. Once i got over that and my body adapted, it was no problem at all.
After doing this for a year, being full just makes me feel sluggish n slow... so even on days i do eat, I eat most of my calories at the end of the day.
Also, I am the type of person who functions very well on low-carbs. I suspect that people who are able to handle lots of carbs with no problem may have more trouble with this, perhaps due to better insulin sensitivity.