Preoperative nutritional interventions in morbid obesity: impact on body weight, energy intake, and eating quality.

BACKGROUND: Although the benefits of preoperative weight loss and adequacy of dietary patterns in bariatric surgery is well-recognized, the nutritional strategies in the preoperative period have been scarcely investigated. We aimed to evaluate the impact of intensive and standard nutritional interventions on body weight, energy intake, and eating quality. METHODS: This is a retrospective study in which 32 patients undergoing intensive nutritional intervention, with low-calorie diet (10 kcal/kg) and biweekly visits, were pair-matched by age, sex, and body mass index with 32 patients under a standard nutritional intervention, based on a general dietary counseling. Twenty-four-hour food recall was used to assess energy intake and to derive healthy eating index (HEI). The follow-up preoperative period varied from 8 to 16 weeks. RESULTS: Weight loss was observed in 72% of the patients from the intensive intervention group and 75% of the patients from the standard intervention group. According to the mixed model analysis, time effect on weight loss in both groups was significant (P = 0.0002); however, no difference was found between the intervention groups (P = 0.71). The time effect was significant in both groups for energy intake reduction as well (P < 0.0001), but no difference was found between the intervention groups (P = 0.25). Improvement of eating quality was expressed by the nutrient score of the HEI that increased significantly overtime (P = 0.02), also without distinction between the groups (P = 0.61). CONCLUSION: Both intensive and standard nutritional interventions promoted weight loss, energy intake reduction, and improvement of eating quality in morbidly obese patients during preoperative period.

Nutritional management of weight regain after bariatric surgery.

BACKGROUND: The aim of this study was to propose dietetic guidelines for the nutritional management of weight regain in Roux-en-Y gastric bypass (RYGB) patients. METHODS: Thirty patients more than 2 years after RYGB surgery were followed up once every 15 days for at least 3 months. We collected from the medical records weight before surgery, excess weight, minimum weight reached 2 years after surgery, and percent of body fat before the operation. Current weight and bioelectrical impedance analysis were assessed at every appointment. The prescribed diet had a low glycemic load with 45% of carbohydrates, 35% of protein (80 g for women and 100 g for men) and 20% of fat, three servings of dairy products, and a supplement of soluble fibers (15 g/day). RESULTS: The patients had a previous average weight regain of 8 kg (+/-19). Forty percent of the sample had an excess weight loss (EWL) of less than 50%. After the intervention, 86% of the patients lost weight. The mean weight lost was 1.8 kg in the first month, 1.2 kg in the second month, and 1.3 kg in the third. Half of the sample with unsuccessful weight loss achieved an EWL of at least 50%. The failure rate of the group dropped from 40% to 20%. The percentage of body fat declined from 36.2% to 34% (p < 0.001). CONCLUSION: Despite the short period of time, we observed that the nutritional counseling reduced the weight of patients with previous weight regain. There was also a reduction in body fat, which improves the perspective of weight maintenance in the future.

Snack-eating patients experience lesser weight loss after Roux-en-Y gastric bypass surgery.

BACKGROUND: In bariatric surgery patients, weight loss and long-term weight maintenance are related to food intake and eating patterns. To improve the diet orientation in the bariatric surgery postoperative period, we assessed the postoperative eating patterns and related them to weight loss. METHODS: This was a transversal, analytical, and descriptive study that assessed body mass index (BMI) values and percentage of excess weight loss (%EWL) in patients who had undergone Roux-en-Y gastric bypass (RYGBP) surgery. The eating pattern and energy intake were investigated based on data collected through a 4-day food intake record. From these records, we assessed the number of daily meals, the quantity of food per meal, and calorie value of snacks between main meals. Based on these records, patients were classified under sweet-eating, snack-eating, or normal-eating patterns. RESULTS: Seventy-five patients met our inclusion criteria. The normal-eating pattern group was the one with the greatest weight loss with an average %EWL of 71.4 +/- 21%, followed by the sweet-eating pattern with 69.9 +/- 16.8%, and the snack-eating pattern with 56.4 +/- 16.7%. This difference was significant only between the first and the third group (p = 0.04). The snack-eating patients had the highest caloric intake and highest number of daily meals (p < 0.01). CONCLUSION: Postoperative eating pattern influenced postbariatric surgery weight loss. In the present study, the snack-eating pattern was associated with the worst weight loss outcome, followed by the sweet-eating and normal-eating patterns. A screening and a differential approach to patients according to their eating patterns may lead to better results of weight loss.

Relation between carbohydrate intake and weight loss after bariatric surgery.

BACKGROUND: Weight loss and long-term weight maintenance in bariatric surgery patients are related to maintaining satiety. It can be related to glycemic load (GL) and carbohydrate (g CHO) intake. The aim of this study was to investigate the effect of g CHO and GL and in weight loss on patients who had undergone bariatric surgery. METHOD: The following measurements/calculations were conducted as follows: current body weight (kg), current BMI, percentage of excess weight loss (PEWL), average monthly weight loss (AMWL), energy intake (kcal per day), and GL calculation. Correlations were found among the studied variables. A multiple linear regression analysis of diet variables executed with GL and weight loss. RESULTS: The population presented 66% of EWL. The average of total energy intake (TEI) was 1220+/-480, and the calculated GL resulted in an average of 73.2. Negative correlations were found between AMWL and TEI (p=0.04), and between AMWL and GL (p=0.009); furthermore, a negative correlation was found between carbohydrate intake in grams and AMWL (p=0.003). A positive correlation (p=0.017) was found between GL and TEI. Weight loss and GL were also correlated. Among the intake variables, GL and g CHO consumed are held accountable for 62 percent of AMWL. The multiple linear regression analysis showed that GL and carbohydrate grams (g CHO) account for 62% of AMWL. CONCLUSION: The glycemic load and grams of carbohydrate are intake factors that can be useful tools in weight loss and long-term weight maintenance on patients who have undergone Roux-en-Y Gastric Bypass (RYGB).