There is the Newcastle Diet, and there is also the Fast 800 diet Both are similar in concept and are derived from the Slimfast / Optifast/ Cambridge Diet plans. In fact they use those very shakes to create an 8oo Kcal + low fat ultra low calorie plan. The Newcastle diet is NHS approved and has been demonstrated to be beneficial for treating diabetes (Type 2). You should only attempt the diet if you have a BMI exceeding the entry requirement (>39 from memory), and you will be encouraged to lose a minimum of 15 kg in 8 to 12 weeks.
An alternative strategy which many on this forum follow is the Low Carb Healthy Fat (LCHF) diet which does not have a BMI restriction and which I have used successfully to reduce my diabetes and my weight for the last 8 years.
