And if you're not getting the right nutrients, keto may actually lead you to gain weight, not lose it. Compared to the low-fat craze in the '90s, the ketogenic diet seems to go against all diet logic. Because instead of cutting out fat, you eat large amounts of it for every meal. The ketogenic diet is not a commercial meal plan, so there are no costs or membership fees associated with starting this diet. But, depending on your current eating habits, this eating approach may increase your food bill.