I recommend a low-carbohydrate, high-fat diet if you have any issues related to insulin sensitivity, such as diabetes (Type I and II) or Alzheimer’s disease (aka Type 3 diabetes). I also recommend keto if you’re trying to lose weight (fat) and if you have impaired metabolic flexibility. You can tell if you’re metabolically flexible if you can skip a meal or two without major cravings or getting hangry.