Been there, done that. In the first few months, there seem to be some hormonal adaptations I liked, but in the long term, say >8 months, the good effects went away.
I then realized that, for certain activities, my body was bound and determined to burn glucose, and simply got way more efficient at gluconeogenesis (forming glucose from protein). Not good.
I also developed a super-hyper-sensitivity to carbs, releasing too much insulin when I did eat carbs.
And furthermore, I found that the diet was deficient in certain vitamins and minerals, and that I feel better getting foods that contain those nutrients, rather than just supplementing.