Effect of Increased Colonic Propionate on Weight Loss During a Hypo-caloric Diet.

DIET AND OBESITY:

Obesity has reached epidemic proportions worldwide. In the United Kingdom, 58% of adult women and 65% of adult men are either overweight or obese (Health and Social Care Information Centre 2014), with the expectation that rates will increase (Ng et al. 2014). Obesity, mainly caused by a chronic positive energy balance, is a known risk factor that contributes to the development of type 2 diabetes and cardiovascular diseases, and the subsequent morbidities and mortalities (Kopelman 2007). A positive energy balance is inevitable with the composition of current western diet that contain refined (fibre-depleted) carbohydrates that are consumed quickly, and have minimal effects on long-term satiety (Cleave 1974; Heaton 1973).

NONDIGESTIBLE CARBOHYDRATES:

The quality and quantity of diet has changed dramatically over the last fifty years. Of which, carbohydrates have the most significant changes; from unprocessed fruits and vegetables based carbohydrates to more processed cereal based ones (Cordain et al. 2005). Epidemiological studies have shown that, as a result, ancestral diets had greater amounts of Non-Digestible Carbohydrates (NDC) than modern diets (>100g/day compared to <15g/day) with the inclusion of more indigestible intact cell wall plant material, such as tubers, grasses and sedges (Eaton 2006). A strong association has been established between increased weight gain with decreased NDC intake (Liu et al. 2003). Furthermore, increasing intake of NDC have shown to induce satiety and improve body composition in animals (So et al. 2007) and humans (Bouché et al. 2002).

LOW CALORIC HIGH NDC DIET IN LOSING WEIGHT Applying energy-restricted diets is one of the first steps to treat obesity. However, weight regain in weight maintenance period could happen due to resting energy expenditure reduction and lean mass loss. The inclusion of specific foods to the nutritional intervention is being investigated in order to produce persistent weight losses (Abete et al. 2008). It was suggested earlier that the addition of high fibre NDC foods to a hypocaloric diet would help reducing the incidence of metabolic syndrome and increasing the dietary compliance (Hermana et al, 2011). The high fibre content in combination with a low glycemic index diet, can both result in higher satiety effects with an increased mitochondrial oxidation, all favour weight loss.