I have a common channel of 175. My surgeon recommended 200 because of the issues he's had at his practice with vitamin deficiencies and bowel issues with the shorter lengths. He was also concerned because I have had past issues with iron deficiency anemia (since my teens) and very low chronic vitamin D. I also have a history of small intestine ulcerations and an autoimmune disease that affects my gut. I'm on meds for depression and PTSD.
I talked him down to 175 cm and he and my GI doctor agreed it would be a safe length. I could have gone lower if I fought for it but I was concerned given the above history so I felt like it was prudent to leave a longer common channel. Post surgery I started to malabsorb my depression meds and have withdrawal, so now I crush one (Pristiq) and take an easier absorbed form of the other twice a day (Wellbutrin). The Rexulti and my ADHD med Adzenys absorb just fine.
I have read that people who are taller often have longer intestines, which would give you a longer common channel with the Hess method. That's something to think about. It is possible if you went with a cookie cutter 100cm length you'd end up too short. This is why the Hess method is so useful. Intestinal length can be estimated with an MRI I believe if you were really curious before surgery and could get it approved. I'd try to argue him down to at least 175cm, I've seen a number of people who have that and lost all their weight. I'm only 2 months out and I'm losing a bit slowly but my body has always been VERY reluctant to let go of weight so I don't think it is due to the common channel. I have not had many bowel issues since a few weeks post surgery though and I suspect that is in part to my longer common channel.
Oh, and I recommend actually measuring out what those common channels look like. That's what helped me decide on 175cm. In my gut I knew 200 cm was too long for me, I'm only 5'4". When I converted the measurements to inches it made much more sense in my brain. I try to make the metric system make sense but I still can't visualize the measurements. LOL
