The adaption to an all-meat diet is a lot more difficult than adapting to a keto or low carb diet. At least for me anyways. I ate a low carb diet for about a year before attempting an all-meat diet and the adaption phase was still a little difficult.

The mental aspect of it all is the cravings and the doubt. This way of eating would be considered as extreme by many people although it really isn't. Only in a modern and cultural context would make this seem extreme. In reality, its logical and has plenty of evidence to support it. Both biological and anthropological evidence. But, eating is learned through acculturation, so it is hard to unlearn things that you have believed since you were a child. It is like learning a new language almost. Also, its just hard to give up some of your favorite foods. Mine was pizza and I dreamed about eating it. My mouth would water just thinking about it. Variety was another thing that I struggled with, but you can find variety in the animal kingdom too.

They physical side of the adaption is also difficult. Many people get muscle cramps. The skin, mouth, and eyes can get dry too. Also, finding energy to do anything is almost impossible. The thought of eating meat and fat is sort of disgusting for the first week. However, after that steak becomes so delicious. My favorite food is now a rib-eye cooked rare. I honestly enjoy it every single day. It always satisifies me for many hours. It took about 6 months for me to physically adapt to this way of eating completely. After 6 months, I felt really good. I had all the energy i wanted, my skin was feeling great, I no longer felt dehydrated, and I have not had a single muscle cramp in 7 years.