effects of different types of carbohydrates in snacks and beverages on glycemia, insulinemia and appetite.

Conditions: Pre Diabetes; Obesity

Summary: the aim of the study is to describe the glycemic, insulinemic and appetitive responses to liquid and solid foods where either soluble fiber or maltodextrin are used as the carbohydrate substrate.

asia has the unenviable reputation as being the epicenter for type 2 diabetes. the asian phenotype has been shown to be most susceptible to diabetes than caucasians. more importantly, the transition from prediabetes to diabetes is more drastic and severe in asians. the glycemic index (gi) was first introduced in 1981 as a classification of the blood glucose raising potential of carbohydrate foods. there is substantial evidence suggesting that consumption of low glycemic index (gi) foods minimize blood glucose fluctuations, and help in the prevention and management of diabetes and prediabetes. given the rising incidence of prediabetes and diabetes in asia, dietary interventions to complement pharmacological management of diabetes are increasingly being encouraged. the majority of studies on gi and glycemic response (gr) have been conducted on caucasian populations. asians have been shown to have a greater gr to the same food compared to caucasians. simple dietary modification such as increasing dietary fiber in a food has been shown to reduce gr. however, it is unclear if a palatable, low-viscous, soluble fiber and maltodextrin have comparable effect. although viscous insoluble fiber has been shown to also suppress appetite, it was unclear if similar effects could be obtained when it is replaced with soluble fiber. using the continuous glucose monitoring system (cgms), henry and his colleagues have demonstrated that exchanging high-gi bread with a low-gi bread could improve the 24h glucose profile. more recently investigators have shown, using the cgms, that the consumption of a low gi breakfast and afternoon snack was capable of attenuating 24-hour blood glucose profiles, minimizing glycemic excursions and reducing food intake in healthy asian males. these simple dietary interventions appear to be an acceptable approach in improving overall glycemia and energy balance in asians.

Eligibility criteria:
inclusion criteria: * healthy chinese male subjects aged between 21 and 60 years * either one of the three criteria: * normal weight (body mass index 18.5-22.9 kg/m2) and fasting blood glucose 5.0-6.0mmol/l * overweight (body mass index 23.0 - 30.0 kg/m2) and fasting blood glucose 5.0-6.0mmol/l * overweight (body mass index 23.0 - 30.0 kg/m2) and fasting blood glucose \<5.0mmol/l exclusion criteria: * do smoke * have any metabolic diseases (such as diabetes, hypertension etc) * have known glucose-6-phosphate dehydrogenase deficiency (g6pd deficiency) * have medical conditions and/or taking medications known to affect glycemia (glucocorticoids, thyroid hormones, thiazide diuretics) * have any major organ dysfunction (e.g. cardiovascular, respiratory, hepatic, renal, gastrointestinal) that may influence taste, olfaction, appetite, digestion, metabolism, absorption or elimination of test foods, nutraceutical or drug * consume fiber supplements or other supplements that is likely to interfere with study outcomes * have any severe food allergy (e.g. anaphylaxis to peanuts) * have any known allergies to any food components of the study protocol * have active tuberculosis (tb) or currently receiving treatment for tb * have any known chronic infection or known to suffer from or have previously suffered from or is a carrier of hepatitis b virus (hbv), hepatitis c virus (hcv), human immunodeficiency virus (hiv) * is a study team member or an immediate family of any study team member. immediate family member is defined as a spouse, parent, child, or sibling, whether biological or legally adopted. * is enrolled in a concurrent research study judged not to be scientifically or medically compatible with the study of the cnrc. * partake in sports at the competitive and/or endurance levels * intentionally restrict food intake * have poor veins impeding venous access * have any history of severe vasovagal syncope (blackouts or near faints) following blood draws