So many food issues in America.
Keto works because it resets your body's fat set point downwards by altering amounts of the hormone leptin.You feel full after consuming fewer calories.
Its critical to get the amounts of protein, fat and carb right, and it is tempting to up the carb portion. You really do need to keep carbs ultra low and especially avoid sugar, even sugar in fruit.
Plant based diets have hidden risks. Plants produce v. small amounts of toxins, actual poisons, that the plant uses to repel and deter insect pests. Some types of plant have much more of these than others. When you have a totally plant based diet, you ingest too many of these micro toxins and you actually start to poison your body.
As for fiber, interesting to learn that the Inuits thrived ona carnivore diet without any fiber at all. I never knew that before.