In my biochemistry class at MIT during undergrad, the professor showed during the section on the krebs cycle that the pop-culture concept of "ketogenic diet" is

In my biochemistry class at MIT during undergrad, the professor showed during the section on the krebs cycle that the pop-culture concept of "ketogenic diet" is almost never actually doing what people believe. To force your body into a purely ketone metabolism, you'd need to restrict not just carbohydrates but also protein. If a person is eating a high-fat, high-protein diet, their body will make glucose/glycogen from that. Not to say there isn't value in a low-sugar diet. There's a whole cascade of other things happening metabolically in response to blood sugar. Just that the notion of "burning ketones instead of glucose" is a medical myth, like "depression is because you have too little serotonin in your brain".