I went the full keto route a few years back. Lost tons of weight, got tons of attention from the fairer sex.
Overdid it, developed a narcissist personality just so that I could maintain the crazy diet (you have to get pretty Spartan with it at some point), and turned into a complete asshole.
Started getting back into eating normal foods. Fine, I'm not turning any heads, but I'm happy and can think properly.
I will see how long I will be able to keep it up. It already is a huge challenge after a week.