Clinicians should encourage patients undergoing sleeve gastrectomy to reduce ultra-processed foods and increase proteins, fruits, and vegetables post-surgery.

After undergoing sleeve gastrectomy, patients should reduce their intake of ultra-processed foods and augment high-quality protein sources, fruits, and vegetables to attain optimal clinical outcomes, according to a study published in the European Journal of Medical Research.

“To our knowledge, no study has determined the major dietary patterns of patients undergoing bariatric surgery and the association between these dietary patterns and weight loss and weight loss composition after the surgery,” wrote Nazanin Mosleh, PhD, and colleagues.

The researchers conducted a cross-sectional study to identify patients’ common dietary patterns after sleeve gastrectomy. The researchers examined the relationships between diet, total weight loss, and the percentage of total weight loss as fat mass loss (%FML) and fat-free mass loss (%FFML).

The study cohort comprised 146 patients who underwent sleeve gastrectomy 2 to 4 years prior. The researchers used principal component analysis for the 19 food groups to establish dietary patterns. They computed %FML and %FFML relative to total weight loss and defined suboptimal clinical response as total weight loss less than 25%.

Results revealed that two principal dietary patterns were preserved. The researchers discovered that at midterm after bariatric surgery, patients who adhered more to a diet high in fast foods, soft drinks, processed meats, sugary snacks, salty snacks, grains, and organ meats were more likely to have a suboptimal clinical response and excessive FFML.

“Previous studies have demonstrated the adverse associations between ultra-processed foods and body composition, such as higher body fat and lower lean mass. Researchers have proposed various mechanisms to explain the negative associations, such as reduced protein intake, increased energy, and refined sugar due to unbalanced diet composition, increased consumption of advanced glycated end-products, alterations in the intestinal microbiome, and changes in gut-brain signaling of satiety,” the researchers said.

On the other hand, lower odds of suboptimal clinical response correlated with better adherence to nutritional plans that included fruits, dairy, vegetables, legumes, eggs, nuts, red meats, poultry, and fish. The authors noted that these correlations were independent of energy intake.

“To achieve the best postoperative outcome, this study recommends encouraging patients undergoing bariatric surgery to modify their dietary habits by reducing their intake of ultra-processed foods and increasing their consumption of high-quality protein sources, fruits, and vegetables,” Dr. Mosleh and colleagues concluded.