On the Cruise Control Diet we do not recommend the consumption of fruit smoothies as we do not recommend having any meal in "liquid form". Our recommendation is to have 1-2 servings of fruit per day while on the program.
Smoothies usually consist of more servings of fruit than what we recommend. Often times smoothies will also be made with frozen fruits that have some form of added syrup to them. This added sugar syrup will negatively impact your success on the program.