People ate the Keto way for thousands of years - it's a natural way of eating for humans. People hunted for their foods and ate berries and other fruits when they could find them (so it wasn't all year long like we do). They ate roots and other things, as well.
The ketogenic diet REVERSES diabetes 1, non-alcoholic fatty liver disease, relieves MS symptoms, lowers inflammation in the body so that people with arthritis feel gobs better, it relieves brain fog, gives a person more energy and more.
Do your research.
And also, the ketogenic diet is not about eating bacon all day, or even every day. It's about putting our bodies into the natural state of ketosis and burning fat for fuel, not empty junky carbs.