This note is a complementary follow-up to last week’s note. Bariatric surgery was discussed at the weight set point workshop. One of the presenters, Dr Lee Kaplan, reported that bariatric surgery appears to alter the entire homeostatic collection of pathways in the opposite direction of that seen with weight loss from a calorie-restricted diet and thus may work via alteration of the weight set point (Ref 1). He noted that people who successfully reduce weight following bariatric surgery experience a dramatic loss of hunger but do not have reduced energy expenditure.
While researching for longer term outcomes of bariatric surgery, I came across a recent publication from March 2021 called “Patients’ views of long-term results of bariatric surgery for super-obesity: sustained effects, but continuing struggles” (Ref 2). The paper was written by Swedish researchers. The aim of the study was to explore, in depth, patients' experiences of living with a bariatric surgery procedure for more than a decade.
Between 2006 and 2007, a randomised controlled trial had been conducted in Gothenburg and Oslo whereby 60 patients had had one of two bariatric surgery procedures. The patients had undergone a Roux-en-Y gastric bypass (RYGB) or biliopancreatic diversion with duodenal switch (BPD/DS).
The Roux-en-Y gastric bypass procedure is usually shortened to “gastric bypass” and this term captures what happens – the stomach is bypassed. This surgery reduces the size of the upper stomach to a small pouch about the size of an egg. This makes the person feel full quickly and they are unable to eat as much. This also means that food doesn't go where it should for digestion purposes and nutrients are not absorbed as they should be and there are nutrition related health consequences, as a result of this.