Low carb diet food is a great way to gain weight. Every low carb diet store I’ve seen has gone out of business, because low carb diet foods don’t help you lose weight. Low carb diet foods make you gain weight. The calories in low carb bread, cookies. pie, ice cream cheesecake, pizza, pancakes, etc. – are generally higher than the calories in the full carb versions. Protein and carbohydrate have 4 calories per gram. Fat has 9 calories per gram. Low carb diet foods substitute fat calories for carbohydrate calories, so the final fake product is generally higher in calories. You can’t eat all the low carb calories you want, and lose weight.