A recent investigation has sparked fresh concerns about the lasting impact of bariatric operations, particularly those involving gastric bypass surgery.
The findings from Lund University in Sweden suggest that the significant metabolic changes triggered by gastric bypass procedures occur predominantly in the immediate aftermath of the operation. Many of these metabolic indicators revert to their pre-surgery levels within a year.
While patients often initially experience positive outcomes such as weight loss and diabetes remission, the study’s results cast doubt on the sustained durability of these benefits, which were previously assumed to be more enduring.
The research focused on the metabolic effects of gastric bypass surgery. Researchers examined a cohort of overweight individuals, both with and without type 2 diabetes, who had undergone gastric bypass operations in Sweden.
Lead author of the study, Peter Spégel, an associate professor of molecular metabolism at Lund University, emphasised the importance of moving beyond simple weight tracking: ‘Just following up on people’s weight can be a blunt instrument for studying the effects of the procedure. Our study provides a greater understanding of what happens to the metabolism in connection with a gastric bypass operation.’
The investigation underscored that the most substantial metabolic transformations occur immediately post-operation. Still, within a year, a significant portion of participants exhibited metabolite and fat levels nearing those recorded before surgery.
This revelation challenges earlier studies that suggested enduring and profound metabolic improvements.
Nils Wierup, a professor of neuroendocrine cell biology at Lund University and one of the study’s principal authors, noted: ‘We could see the changes while the participants still had a low BMI after the operation. By studying metabolism, we can obtain a clear indication that unhealthy changes are on the way. We hope the knowledge can be used in follow-up to implement preventive measures.’
One notable discovery from the study was the reduction and subsequent elevation in the concentration of a specific type of amino acids following the procedure. These amino acids are typically elevated in individuals with insulin resistance and are associated with an increased risk of developing type 2 diabetes.
Peter Spégel said: ‘One conclusion we draw is that the risk of developing type 2 diabetes is considerably reduced after the operation among individuals who do not have the disease, but one year later, we see an increased risk again. Among individuals who already had type 2 diabetes at the time of the surgery, we see a remission of the disease. Still, the risk of the disease returning then increases over time.’
Despite shedding light on potential setbacks, Nils Wierup remains cautiously optimistic about the benefits of bariatric operations, particularly their impact on diabetes remission:
‘One advantage of bariatric operations is that most people with type 2 diabetes see a remission of their disease afterwards. And even though a large percentage of individuals who undergo this procedure gain weight afterwards, it’s usually not a return to the same weight as before.’
While further research is needed to draw definitive conclusions, the findings prompt a re-evaluation of the understanding of the enduring effects of bariatric procedures.
The study appears in the journal Obesity.
