Amy Jo Riggs

Changes in energy expenditure associated with ingestion of high protein, high fat versus high protein, low fat meals among underweight, normal weight, and overweight females

BackgroundMetabolic rate is known to rise above basal levels after eating, especially following protein consumption. Yet, this postprandial rise in metabolism appears to vary among individuals. This study examined changes in energy expenditure in response to ingestion of a high protein, high fat (HPHF) meal versus an isocaloric high protein, low fat (HPLF) meal in underweight, normal weight, or overweight females (n = 21) aged 19–28 years.MethodsEnergy expenditure, measured using indirect calorimetry, was assessed before and every 30 minutes for 3.5 hours following consumption of the meals on two separate occasions. Height and weight were measured using standard techniques. Body composition was measured using bioelectrical impedance analysis.ResultsSignificant positive correlations were found between body mass index (BMI) and baseline metabolic rate (MR) (r = 0.539; p = 0.017), between body weight and baseline MR (r = 0.567; p = 0.011), between BMI and average total change in MR (r = 0.591; p = 0.008), and between body weight and average total change in MR (r = 0.464; p = 0.045). Metabolic rate (kcal/min) was significantly higher in the overweight group than the normal weight group, which was significantly higher than the underweight group across all times and treatments. However, when metabolic rate was expressed per kg fat free mass (ffm), no significant difference was found in postprandial energy expenditure between the overweight and normal groups. Changes in MR (kcal/min and kcal/min/kg ffm) from the baseline rate did not significantly differ in the underweight (n = 3) or in the overweight subjects (n = 5) following consumption of either meal at any time. Changes in MR (kcal/min and kcal/min/kg ffm) from baseline were significantly higher in normal weight subjects (n = 11) across all times following consumption of the HPHF meal versus the HPLF meal.ConclusionThere is no diet-induced thermogenic advantage between the HPHF and HPLF meals in overweight and underweight subjects. In contrast, in normal weight subjects, ingestion of a HPHF meal significantly increases MR (69.3 kcal/3.5 hr) versus consumption of a HPLF meal and provides a short-term metabolic advantage.

Body Weight Misconception and Maintenance Among Female African American College Students

The purpose of this study was to compare self-reported weight classifications with objectively measured body mass index (BMI) and weight management motivations among female African American (AA) students in a mid-size southeastern university in a rural setting. Participants were recruited from general health class to complete a brief survey, and their height/weight was measured. Chi-square tests were performed to investigate whether mismatch occurred between self-perceived weight classification and directly measured BMI, and the relationship between body weight loss effort and self-perceived body weight. Among the women who were classified as overweight or obese based on direct measurements, 29.63% and 11.59% felt they were normal weight, respectively. Almost one third of the overweight college females perceived their body weight incorrectly and body weight perception is a significant factor driving the body weight control efforts. Appropriate programs for body weight perception and weight control behavior for AA female college students should be developed and implemented.