I don't do the smoothies as they aren't my thing, but as a diabetic the Metformin and Victoza can cause that feeling. I also eat a bunch of raw veggies (mini bell peppers, brocolli, carrots), some raw fruit and a diabetic friendly diet, and I have never had an issue of bowel control (but I have had the cramping and feeling of "got to go now!!"). In the instance of that "feeling" I just find the nearest depository and take care of business.
Also drinking a bunch of water daily helps keep things moving so you don't experience the cramping. I have more issues in that departement when I don't drink at least three liters of water a day (but that is on top of my pot of black coffee per day).