Very low-calorie diet in candidates for bariatric surgery: change in body composition during rapid weight loss

Abstract

OBJECTIVE: To analyze the changes in the body composition of morbidly obese patients induced by a very low-calorie diet. METHODS: We evaluated 120 patients selected from a university hospital. Body composition was assessed before and after the diet provided during hospitalization, and changes in weight, body mass index, and neck, waist and hip circumferences were analyzed. Bioimpedance was used to obtain body fat and fat-free mass values. The data were categorized by gender, age, body mass index and diabetes diagnosis. RESULTS: The patients consumed the diet for 8 days. They presented a 5% weight loss (without significant difference among groups), which represented an 85% reduction in body fat. All changes in body circumference were statistically significant. There was greater weight loss and a greater reduction of body fat in men, but the elderly showed a significantly higher percentage of weight loss and greater reductions in body fat and fat-free mass. Greater reductions in body fat and fat-free mass were also observed in superobese patients. The changes in the diabetic participants did not differ significantly from those of the non-diabetic participants. CONCLUSIONS: The use of a VLCD before bariatric surgery led to a loss of weight at the expense of body fat over a short period, with no significant differences in the alteration of body composition according to gender, age, body mass index and diabetes status.

Implementation of a very low calorie diet program into the pre‐operative model of care for obese general elective surgery patients: Outcomes of a feasibility randomised control trial

“…Similar weight loss of between 4% and 15% has been reported in non‐bariatric surgery patients using a pre‐surgical calorie restricted diet 21, 32, 33, 38 . A high proportion of weight loss (85%) was from FM in participants receiving the VLCD intervention, likewise other studies evaluating low calorie diets on body composition showed 68.9 ‐ 85% of weight loss was from a reduction in FM without excessive loss of muscle mass 39, 40 . Using BIA to measure body composition is not without flaw, as results can be influenced by body water distribution and body morphology in individuals with obesity, potentially overestimating body FM 41 …”

Non-Surgical Interventions for Hospitalized Adults with Class II or Class III Obesity: A Scoping Review

“…Sample sizes of the studies ranged from six 51 to 259, 58 with dropout rates ranging from 0% 55 , 56 , 58 to 46% 48 at 5-year follow-up. Mean (SD) age of participants ranged from 28.5 (7.2) 50 to ≥60 years.…”

“…Mean (SD) age of participants ranged from 28.5 (7.2) 50 to ≥60 years. 56 , 58 Mean (SD) BMI of the studies ranged from 36 (5) 54 to 64.3 (2.1). 51 Obesity treatment was the primary reason for admission in eight articles, 47–51 , 53 , 56 , 57 rehabilitation for two articles, 55 , 58 and acute care for two articles, 52 , 54 (including cellulitis, 52 asthma, 52 respiratory infection, 52 cancer, 54 pancreatic disease, 54 trauma, 54 and gastrointestinal disorders 54 ) ( Table 2 ).…”

“…The clinical profession/professions of the person/s delivering the interventions was clearly defined in five studies, 47 , 49 , 54 , 55 , 58 partially reported in two studies 50 , 51 and not reported in three studies. 52 , 56 , 57 Medical officers, 47 , 49–51 , 54 , 55 , 58 nurses, 47 , 49 , 54 physiotherapists, 47 , 49 , 50 , 54 , 55 , 58 dietitians, or nutritionists, 47 , 49–51 , 53 , 55 , 58 and psychologists 47 , 49–51 , 53 , 55 , 58 were the disciplines who most frequently delivered interventions. Other disciplines reported were exercise physiologists, 49 , 55 a pharmacist, 54 a chef, and a social worker, 47 with one study reporting clinical staff.…”

Establishment of Adequate Nutrient Intake Criteria to Achieve Target Weight Loss in Patients Undergoing Bariatric Surgery

“…Nutrition prescription is an important component of nutritional interventions for weight management. In particular, calorie prescription is the key for guiding intake amounts [ 20 ]. Over time, energy intake shows an increasing trend, with values of 1500, 1700, 1800, 1900, and 2000 kcal/day at 6 months and 1, 2, 3, and 4–10 years post operation [ 9 ].…”