Background: Very low calorie diet (VLCD) is routinely used in programs for treatment of obesity and before bariatric surgery in order to reduce risk of postoperative complications. Aspartame, an artificial sweetener, is commonly used in VLCD and is well approved as a food additive without any adverse effects. The development of a new fructose containing VLCD formula without aspartame raises questions as to effects on glucose and lipid control.
Methods: As part of an ongoing study of a novel bariatric surgery procedure, twenty-five obese subjects with mean body mass index (BMI) 39.8 kg/m2 and mean age of 48.8 years enrolled in a single center observational study. Seven subjects presented with type 2 diabetes mellitus. The subjects underwent four weeks dietary treatment with VLCD Slanka (Slanka). Blood samples including fasting plasma glucose, HbA1c, cholesterol and triglycerides were performed at start and after four weeks of diet. Blood pressure and weight were noted.
Results: All subjects completed the diet without any adverse events. Mean weight reduction was 8.2 kg with 95% confidence interval 7.1-9.2 kg (p = 0.001). Excess weight (i.e. proportion of weight exceeding BMI 25) loss decreased by median 19.5% (inter quartile range (IQR) 16,8-24,2). Median fasting plasma glucose was at inclusion 5,6 mmol/l (IQR 5,3-6,8) and after diet 4.8 mmol/l (IQR 4,6-5,2) (p = 0.001). Median HbA1c changed from 39 mmol/mol (IQR 37-44) to 37 mmol/mol (IQR 35-43) (p = 0.001). There was also significant reduction in cholesterol and triglyceride levels as well as in systolic blood pressure. Changes in other monitored blood chemistry values were without clinical importance.
Conclusion: Four weeks treatment with fructose containing VLCD of obese subjects preparing for bariatric surgery gave a substantial weight reduction without any significant negative metabolic effects.