Animal Protein Intake Is Associated with Obesity Remission After Roux-en-Y Gastric Bypass: an Isocaloric Replacement...

Some patients do not have the expected weight loss, and the post-surgical diet may partially explain these differences.

To estimate the impact of macronutrient substitution on obesity remission after RYGB, considering the protein source.

This study included 58 patients undergoing RYGB. Data collection was performed preoperatively, 3 and 12 months after surgery. Eight participants dropped out of the study at 3 months, and the others remained for 12 months. The foods consumed were registered using a 24-h, 3-day food recall. For the isocaloric substitution analysis, foods were classified according to the protein source. The groups were compared using hypothesis tests, and Cox proportional hazard ratio regression was used to analyze isocaloric substitution.

At three months after surgery, every 5% energy from plant protein replaced by animal protein increased by 3.50 [CI 1.204 - 10.205; p = 0.021] the probability of obesity remission. Stratified analysis by protein groups indicated that replacing vegetable protein with white meat was positively associated with remission of obesity. Every 5% vegetable protein replaced with white meat increased by 3.20 [CI 1.026 - 9.981; p = 0.045] the probability of obesity remission. Both results were independent of age, body mass index (BMI), and the presence of comorbidities.

The results suggest that the consumption of animal proteins after RYGB, mainly white meat, favors weight loss.