Peter Attia's ketogenic diet involved limiting protein to 100-110 grams and making fat approximately 90% of total calories.

“it was really had to limit protein to about a hundred to 110 grams if I went over that I would get kicked out and so fat made up about 90% of my total calories and so there's only so many ways you can get that much fat and the most efficient way is actually salad with olive oil I mean I couldn't believe the amount of vegetables I had to consume to stay in ketosis you know obviously had to have two huge salads a day where I would make my own dressing which was a heavy olive oil-based dressing”