-
1دورية أكاديمية
المؤلفون: David J. Clayton, Stuart J.H. Biddle, Tyler Maher, Mark P. Funnell, Jack Sargeant, James King, Carl Hulston, David Stensel, Lewis James
مصطلحات موضوعية: Medical and Health Sciences not elsewhere classified, Intermittent energy restriction, Intermittent fasting, Insulin sensitivity, Type-2 diabetes, Weight management
الوصف: Intermittent energy restriction (IER) involves short periods of severe energy restriction interspersed with periods of adequate energy intake, and can induce weight loss. Insulin sensitivity is impaired by short-term, complete energy restriction, but the effects of IER are not well known. In randomised order, 14 lean men (age: 25 (SD 4) y; BMI: 24 (SD 2) kg·m-2; body fat: 17 (4) %) consumed 24 h diets providing 100% (10441 (SD 812) kJ; EB) or 25% (2622 (SD 204) kJ; ER) of estimated energy requirements, followed by an oral glucose tolerance test (OGTT; 75g glucose drink) overnight fasted. Plasma/ serum glucose, insulin, non-esterified fatty acids (NEFA), glucagon-like peptide-1 (GLP-1), glucose-dependant insulinotropic peptide (GIP) and fibroblast growth factor-21 (FGF21) were assessed before and after (0 h) each 24 h dietary intervention, and throughout the 2 h OGTT. Homeostatic model assessment of insulin resistance (HOMA2-IR) assessed the fasted response and incremental (iAUC) or total (tAUC) area under the curve were calculated during the OGTT. At 0 h, HOMA2-IR was 23% lower after ER compared to EB (P<0.05). During the OGTT, serum glucose iAUC (P<0.001) serum insulin iAUC (P<0.05) and plasma NEFA tAUC (P<0.01) were greater during ER, but GLP-1 (P=0.161), GIP (P=0.473) and FGF21 (P=0.497) tAUC were similar between trials. These results demonstrate that severe energy restriction acutely impairs postprandial glycaemic control in lean men, despite reducing HOMA2-IR. Chronic intervention studies are required to elucidate the long-term effects of IER on indices of insulin sensitivity, particularly in the absence of weight loss.
-
2دورية أكاديمية
المؤلفون: Lewis James, Tyler Maher, Stuart J.H. Biddle, David R. Broom
مصطلحات موضوعية: Medical and Health Sciences not elsewhere classified, Appetite, Energy balance, Weight gain, Obesity, Portion size
الوصف: There is a paucity of data examining the effect of cutlery size on the microstructure of within-meal eating behaviour or food intake. Therefore, the present studies examined how manipulation of spoon size influenced these eating behaviour measures in lean young men. In study one, subjects ate a semi-solid porridge breakfast ad libitum, until satiation. In study two, subjects ate a standardised amount of porridge, with mean bite size and mean eating rate covertly measured by observation through a one-way mirror. Both studies involved subjects completing a familiarisation visit and two experimental visits, where they ate with a teaspoon (SMALL) or dessert spoon (LARGE), in randomised order. Subjective appetite measures (hunger, fullness, desire to eat and satisfaction) were made before and after meals. In study one, subjects ate 8 % less food when they ate with the SMALL spoon (SMALL 532 (SD 189) g; LARGE 575 (SD 227) g; P=0·006). In study two, mean bite size (SMALL 10·5 (SD 1·3) g; LARGE 13·7 (SD 2·6) g; P<0·001) and eating rate (SMALL 92 (SD 25) g/min; LARGE 108 (SD 29) g/min; P<0·001) were reduced in the SMALL condition. There were no condition or interaction effects for subjective appetite measures. These results suggest that eating with a small spoon decreases ad libitum food intake, possibly via a cascade of effects on within-meal eating microstructure. A small spoon might be a practical strategy for decreasing bite size and eating rate, likely increasing oral processing, and subsequently decreasing food intake, at least in lean young men.
