Effect of breakfast glycemic index on metabolic responses during rest and exercise in overweight and non-overweight adolescent girls

Abstract

Background/Objectives: The metabolic responses to mixed breakfast meals with different glycemic indexes (GI) and their effects on substrate metabolism during exercise in adolescent girls have not been examined. The interaction with weight status also warrants investigation. This study investigated the effect of mixed breakfast meals containing high GI (HGI) or low GI (LGI) carbohydrates on metabolic responses and fat oxidation during rest and exercise in overweight (OW) and non-overweight (NO) adolescent girls. Subjects/Methods: A total of 8 OW and 12 NO adolescent girls consumed an isoenergetic HGI (GI ¼ 73) or LGI (GI ¼ 44) breakfast 120 min before completing a 30-min treadmill walk at 50% V O 2peak . Results: Peak blood glucose concentration was higher for HGI compared with LGI in OW (P ¼ 0.023), but not NO (P40.05) girls. Blood glucose total area under the curve (TAUC) was 13% higher in HGI compared with LGI in OW (P ¼ 0.006), but only 4% higher in NO (P ¼ 0.072) girls. Plasma insulin data were log e transformed (lninsulin). Plasma lninsulin concentrations were not different between HGI and LGI (P40.05). Peak plasma lninsulin concentration (P ¼ 0.016) and TAUC (P ¼ 0.001) were greater in OW than NO girls. Fat oxidation during postprandial rest and exercise was not different between breakfasts (P40.05). Conclusions:The elevated glycemic response in HGI compared with LGI was more pronounced in OW girls, suggesting a reduced ability to cope with the metabolic demands of the HGI, but not LGI, breakfast. Manipulation of breakfast GI did not alter fat oxidation during rest or subsequent moderate intensity exercise in OW and NO adolescent girls.

Effects of breaking up prolonged sitting following low and high glycaemic index breakfast consumption on glucose and insulin concentrations

“…In line with previous research using similar mixed breakfast meals (Stevenson et al 2009; Zakrzewski et al 2012), the high GI breakfast induced a larger glucose response compared with the low GI breakfast. Somewhat unexpectedly, the postprandial peak in glucose and insulin concentrations was higher in the low GI compared with the high GI breakfast conditions.…”

Breakfasts Higher in Protein Increase Postprandial Energy Expenditure, Increase Fat Oxidation, and Reduce Hunger in Overweight Children from 8 to 12 Years of Age

“…There have been a limited number studies testing the effects of breakfast macronutrient composition on satiety and subsequent food intake in 8-to 12-y-old children, with most studies focusing on the role of glycemic index at breakfast (19,(35)(36)(37)(38). A majority of the studies that have been conducted are in a preschool population and examine the difference of glycemic index on satiety and food intake and not macronutrient distribution of the breakfast (18,19).…”

Breakfast consumption and adiposity among children and adolescents: an updated review of the literature

“…As a common breakfast food, it is possible that RTEC consumption is a proxy for breakfast consumption in general. Other studies have considered macronutrient composition and glycemic index; although experimental studies have found some potential short‐term metabolic and eating behaviour benefits of breakfasts high in protein and/or low in glycemic index/load, evidence is mixed and relationships with anthropometric outcomes unsubstantiated .…”