I have been having U/U GF Huel for about a week. So far, every time I’ve had it, I’ve had a substantial bowel movement within a couple of hours. For context, I have chronic constipation which is related to nerve problems and therefore not at all responsive to fibre. Only two things work for me - lots of hot water (sometimes), and lots of caffeinated coffee. Bisacodyl and Senna worked for a bit but then stopped, and I am yet to try Prucalopride which I have a trial prescription for. (I also take osmotic laxatives, but I’m just talking about stimulant laxatives here.)
The sensation beforehand is slightly uncomfortable, and likewise during, but I’m just amazed that something in Huel is a powerful enough laxative to work for me, since not many things do. I have a sneaking suspicion it’s ground flaxseed, because I’ve had Innocent smoothies before with ground flaxseed that have sometimes had a similar effect, but was wondering if anyone else had any similar experiences or thoughts on what could be causing it.