This yo-yo style of dieting is linked to increased risk of mortality. We all may be used to instant gratification these days, but remember that you’re a human, not a robot. Your body won’t go into ketosis after just one day of eating no bread and all bacon.
NK is when the body shifts to using fat instead of glucose for energy, such as after a prolonged fast. The liver converts fat into ketones which can be used by the brain for energy.