Fiber enrichment of pasta: metabolic effects and diet adherence in obese subjects

BACKGROUND: Low calorie diets are often poorly sustainable in the long term. Soluble Fiber (SF) slows gastric emptying, diminishes meal energy content and increases satiety. Adding SF to popular foods as pasta could be a good solution to improve diet adherence and metabolic parameters of obese patients. OBJECTIVE: to evaluate the effects of low - calorie diets including SF-enriched pasta in obese subjects on self-referred satiety, weight and metabolic parameters (glucose, insulin, glycated haemoglobin- HbA1c, plasma lipids) in a 3-months follow up. METHODS: 30 obese patients (6M/24F, aged 43,4±10.3 years; BMI 33.4±1.56) were randomized into 2 groups; two isocaloric diets were prescribed: a diet with a serving of SF (chicory inulin 2%) enriched and lignin extruded pasta was given to the 1st group (A) every day; the 2nd group (B) had common semolina pasta. Five follow up visits with anthropometric and metabolic measurements were planned. Plasma OGTT (glucose, insulin), HbA1c, total cholesterol, HDL-cholesterol, triglycerides were determined at baseline (T0) and at the end of the study (T1, after 3 months). Overall weight loss and drop out were evaluated. Subjects were asked to report their feeling of satiety and appetite at every visit using a Visual Analogue Scale (VAS 10 CM). Treatment satisfaction had been evaluated by a questionnaire about the characteristics of SF pasta (appearance, colour, texture, stickiness, flavour and taste) with another VAS. RESULTS: The weight loss was kg 6.29±3.62 in group A and kg 1.87±1.66 in group B (p<0.0002); one patient dropped out in group A, 3 in group B. The satiety and appetite VAS score were 7.6±1.1 (t1) in group A and 5.0±1.0 in group B. Group A was more satisfied of the diet plan taste (score of 8,66±0,97 vs. 1.09 (p<0.01); 9,14±0.86 of patients of the A group and 6.07±2.05 (p<0.01) of the B group declared they have eaten 'enough'. HbA1c (p<0.0001) and insulin level after glucose load (at 120') decreased significantly more in the group A than in group B (p<0.002). The diet did not affect lipid profile either in Group A and Group B after three months. CONCLUSION: SF enrichment and lignine extrusion of pasta increase satiety and diet adherence, and improve metabolic parameters.