The American journal of clinical nutrition
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The aims of the present study were to examine possible effects of age and sex on energy expenditure independent of differences in body composition, and to develop prediction equations for individual estimation of energy expenditure. The study is based on 235 female and 78 male subjects ranging in age from 15 to 64 y and with body mass indexes (in kg/m2) ranging from 16.9 to 50.5. Basal metabolic rate (BMR), sleeping energy expenditure, and 24-h energy expenditure were measured with standardized protocols by indirect calorimetry in respiratory chambers. ⋯ When comparing energy expenditure adjusted for body composition and activity between two age groups (20-30 y, n = 98 and 50-65 y, n = 39), BMR was 4.6% lower in the older group (P = 0.04) and there was a tendency toward a lower sleeping energy expenditure in the older group (P = 0.06). No sex difference in any energy expenditure measurement could be found after differences in body composition and activity were taken into account. In conclusion, no sex effect and no linear decrease in energy expenditure was found with increased age and the middle-aged subjects had lower BMR than younger subjects independent of body size, body composition and activity.
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Randomized Controlled Trial Comparative Study Clinical Trial
A prospective randomized study of glutamine-enriched parenteral compared with enteral feeding in postoperative patients.
Plasma amino acids were measured in 17 postoperative subjects randomly assigned to receive for > or = 5 d tube feeding or total parenteral nutrition (TPN) that had identical energy, nitrogen, and glutamine contents. Subjects required gastric or pancreatic surgery for malignancy and were well-matched for age and body mass index. Tube feeding or TPN began on postoperative day 1 and advanced in daily 25% increments to meet goals of 105 kJ . kg body wt-1 . d-1, 1.5 g protein . kg body wt-1 . d-1, and 0.3 g glutamine . kg body wt-1 . d-1. ⋯ Glutamine concentrations did not differ significantly by feeding group, though a trend suggested that glutamine recovered more slowly in the tube-fed than in the TPN-fed subjects. Plasma amino acids otherwise reflected formula composition with ratios of valine to leucine of 1.24 and 3.69 mumol/L in subjects receiving 5 d of tube feeding or TPN, respectively. These findings suggest that glutamine-enriched tube feeding and TPN can result in similar profiles for most plasma amino acids at carefully matched doses.
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Assessment of diet is a critical component of the third National Health and Nutrition Examination Survey (NHANES III), which was designed to describe the health and nutritional status of the US population. We analyzed data collected with the primary dietary assessment instrument used in NHANES III, the 24-h recall, for 7769 nonpregnant adults aged > or = 20 y to investigate underreporting of total energy intake. Underreporting was addressed by computing a ratio of energy intake (EI) to estimated basal metabolic rate (BMRest). ⋯ Underreporting of energy intake was highest in women and persons who were older, overweight, or trying to lose weight. Underreporting varied according to smoking status, level of education, physical activity, and the day of the week the 24-h recall covered. Additionally, underreporting was associated with diets lower in fat (P < 0.01) and alcohol (P < 0.01 in women) when expressed as a percentage of total energy intake.