Recrystallized resistant starch by encapsulation with konjac glucomannan: Structural changes, digestibility, and its effect on glucose response and short-term satiety in mice

The effects of the structure and digestibility of konjac glucomannan (KGM)-recrystallized resistant starch complex (KRS3) on the glycemic response and short-term satiety in mice were investigated. KRS3 samples were prepared by recrystallized debranched starch (RS3) at 50 °C, and then combined with KGM. The RS3 and KRS3 samples displayed an A-type pattern and maintained peak temperature values above 110 °C. With an increase in KGM, the swelling power and apparent viscosity of KRS3 increased. The results of in vitro and in vivo digestion revealed that KRS3 with a resistant starch content ranging from 69.4 % to 78.8 % could effectively maintain postprandial blood glucose levels. KRS3, particularly with 0.5 % KGM, slowed gastric emptying of mice from 82.7 % to 36.6 % and intestinal propulsion rate from 60.9 % to 35.3 %, resulting in strong satiety. RS3 combined with KGM could serve as a new approach to develop RS3 based foods with low glycemic responses and high-satiety.

Dietary strategies to increase satiety

Obesity has a multifactorial etiology. Although obesity is widespread and associated with serious health hazards, its effective prevention and treatment have been challenging. Among the currently available treatment approaches, lifestyle modification to induce a negative energy balance holds a particularly larger appeal due to its wider reach and relative safety. However, long-term compliance with dietary modifications to reduce energy intake is not effective for the majority. The role of many individual nutrients, foods, and food groups in inducing satiety has been extensively studied. Based on this evidence, we have developed sample weight-loss meal plans that include multiple satiating foods, which may collectively augment the satiating properties of a meal. Compared to a typical American diet, these meal plans are considerably lower in energy density and probably more satiating. A diet that exploits the satiating properties of multiple foods may help increase long-term dietary compliance and consequentially enhance weight loss.

Pulse consumption, satiety, and weight management

The prevalence of obesity has reached epidemic proportions, making finding effective solutions to reduce obesity a public health priority. One part of the solution could be for individuals to increase consumption of nonoilseed pulses (dry beans, peas, chickpeas, and lentils), because they have nutritional attributes thought to benefit weight control, including slowly digestible carbohydrates, high fiber and protein contents, and moderate energy density. Observational studies consistently show an inverse relationship between pulse consumption and BMI or risk for obesity, but many do not control for potentially confounding dietary and other lifestyle factors. Short-term (≤1 d) experimental studies using meals controlled for energy, but not those controlled for available carbohydrate, show that pulse consumption increases satiety over 2-4 h, suggesting that at least part of the effect of pulses on satiety is mediated by available carbohydrate amount or composition. Randomized controlled trials generally support a beneficial effect of pulses on weight loss when pulse consumption is coupled with energy restriction, but not without energy restriction. However, few randomized trials have been conducted and most were short term (3-8 wk for whole pulses and 4-12 wk for pulse extracts). Overall, there is some indication of a beneficial effect of pulses on short-term satiety and weight loss during intentional energy restriction, but more studies are needed in this area, particularly those that are longer term (≥1 y), investigate the optimal amount of pulses to consume for weight control, and include behavioral elements to help overcome barriers to pulse consumption.