Most types of fats are healthier than most carbs. Ketogenic diets are among the most healthiest diets to be on but your body needs to be active to some degree while on it. Eskimos lived on a ketogenic diet and never got cancer before being introduced to the western diet consisting of whole grains.
When you severely limit your bodies carb intake and live on a high fat/high protein diet your body utilizes the fat for energy instead of storing the fat. This is why it’s important to be at least slightly active each day to some degree.
I’ve been on this diet and it works. However my love for pizza, pasta and ice cream always does me in.