Diet Change After Sleeve Gastrectomy Is More Effective for Weight Loss Than Surgery Only

Bariatric surgery with or without diet change has become one of the most effective treatments for obesity. The objective of this study was to observe the effects of vertical sleeve gastrectomy (VSG) and diet change in Sprague-Dawley rats on both body and tissue weights.

Eighteen rats were fed with a standard chow diet (SCD) (C group), and 36 rats were fed with a high-fat diet (HFD) (diet-induced obesity (DIO) group). After 8 weeks, the animals underwent VSG, sham surgery or no surgery (NS). After surgery, a third of the rats fed with the HFD changed to the SCD (DIO + C group). Body weight, food and energy intake were recorded daily during the experiment (12 weeks). Food efficiency (%) (FE) was determined from weekly weight gain and weekly kilocalorie consumed measurements.

The DIO group had higher and significant weight gain than the C group at the time of surgery (p < 0.001). The major weight loss (WL) was observed in the DIO + C-VSG group, during the 4 weeks after surgery. Adipose tissues in the DIO + C-VSG group were drastically reduced and had a weight similar to those in the C-VSG group.

VSG and the diet change combination led to a greater WL, which was maintained during the 4 weeks post-surgery, leading to a normalization of body weight. VSG and diet change also affected most of the tissues, not only adipose, showing a global change in whole body composition.