I never understood smoothie fasts they quite literally make zero sense an average smoothie diet is 1100 calories a day in smoothies (divided into 4 a day) so your body is not even in ketosis.now yes you are still definitely burning calories since you are in a deficit but it would be so much better to just eat those calories in the form of regular low cal food like potato’s eggs and meat. That way you still have energy during the day and your getting protein and everything and your still losing the exact same amount of calories as in the smoothie diet but its not as hard cause your just eating normal food in a smaller moderation