Keto Tone Please make sure that before you start any of these crash diets to consult with your doctor and really think about the reasons you want to go on any extreme diet. If you feel you need to lose weight quick it might be a better idea to go slower and aim at losing 1-2 lbs a week so you can rest assure that you change your eating habits and lifestyle.Stay realistic with your goals and realize that any of the crash diets are just a short-term solution.