Keep in mind that the doctor is getting nutritional ketosis confused with a much more dangerous condition called ketoacidosis. These are two different conditions.  Ketoacidosis is mostly  a concern for Type 1 diabetics and others whose bodies are unable to make or process insulin correctly. Ketoacidosis usually develops when a person with type 1 diabetes develops an serious infection, has a heart attack or other debilitating illness. It is accompanied by dehydration, high blood sugars and is precipitated by the inability of the sick patient to administer proper amounts of injected insulin.
Reduced hunger. Many people experience a marked reduction in hunger on a keto diet. This may be caused by an increased ability of the body to be fueled by its fat stores. Many people feel great when they eat just once or twice a day, automatically ending up doing a form of intermittent fasting. This saves both time and money, while also speeding up weight loss.
A keto diet has shown to improve triglyceride levels and cholesterol levels most associated with arterial buildup. More specifically low-carb, high-fat diets show a dramatic increase in HDL and decrease in LDL particle concentration compared to low-fat diets.3A study in the long-term effects of a ketogenic diet shows a significant reduction in cholesterol levels, body weight, and blood glucose. Read more on keto and cholesterol >