I don't know about it being dangerous, but there is not much nutritional value to it. When you use diet shakes such as Slim Fast, you're told to drink the shake twice a day and eat a lowfat meal in addition which gives you nutrition. Also if you're on insulin or meds, you have to give your body some food for the insulin or meds to work on. You can add a little plain yogurt to it also.
Stacey
The Diabetic Pastry Chef