Not hungry, but brain "shuts down" while fasting
I'm new to the forum, and I've been practicing bulletproof intermittent fasting for about 1 week. I'm not feeling any hunger before 2pm, but my brain doesn't seem to run on fats alone.
I feel dopey, like I can't find words, can't think straight. (I'm a research scientist, so thinking is part of my day job.) If it goes too long, then eating a meal won't fix it. It feels like being drugged up, woozy, and may end up as a headache.
Does anyone else have this problem with fasting? I love not being hungry, but it feels like my brain is running out of fuel.
Does this go away once I get used to it?