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Maternal energy requirements increase during pregnancy but the magnitude of this increment is unknown among adolescents. We determined the effects of maternal age and weight status on adjustments in gestational weight gain, resting energy expenditure (REE), and growth among adolescents. Weight, and growth rates of pregnant adolescents (PA) [less than or equal to] 17 y during late pregnancy were compared with changes in nonpregnant adolescents (NPA) over a 5-mo period. REE was also measured monthly in the PA group. Paired t-tests and general linear models for repeated measures were used for the analysis; height was included as a confounding variable. Weight, height, and BMI of the PA and NPA women did not differ at baseline. During the follow-up period, NPA grew 0.94 [+ or -] 30 cm; growth rate was greater in adolescents [less than or equal to]14 y of age (P < 0.001) than in the older subjects. No growth occurred in the PA group. REE tended to increase linearly between 20 and 36 wk of gestation (P = 0.164); the net change in women >14 y (25%) tended (P = 0.164) to be greater than that of younger adolescents (7%). The mean increment of REE from wk 20 to wk 36 was 230 [+ or -] 30 kcal/d (962 [+ or -] 126 kJ/d) and the smallest increase occurred in women with BMI

Enzymatically modified soy proteins have the amino acid profile and functional properties required for dietary support. The objective of this study was to evaluate the nutritional and technological properties of an enzymatically modified soy protein ultrafiltered fraction with bound methionine ([F.sub.1-10]E) to be used as a protein ingredient for infant enteral formulas. [F.sub.10]E was chemically characterized and biologically evaluated. Thirty-six weaning Wistar rats were fed during 3 weeks with a 4% casein-containing diet. Rats were divided into three groups and recovered for 3 weeks with 18% protein-containing diets based on: (1) [F.sub.10]E, (2) casein or (3) soy isolate+methionine. Nutritional indicators were weight gain, protein efficiency ratio, plasma proteins, apparent digestibility and protein in the carcass. Additionally, [F.sub.10]E was added as a protein ingredient of an enteral formula, and its sensory and rheological properties were compared with a hydrolyzed-whey protein commercial formula. [F.sub.10]E contained 68% protein and 5% sulphur amino acids, with 60% of peptides [less than or equal to] 6 kDa. Casein-based and [F.sub.10]E-based diets were comparable (P > 0.05) in weight gain (108 g and 118 g, respectively), protein efficiency ratio (2.7), apparent digestibility (93% and 95%), plasma proteins (5.7 mg/100 ml) and carcass protein (61%), and better than soy isolate-based+methionine diet (P < 0.05). Viscosity of the commercial formula and our formula was similar during a 24-h period. Sensory acceptability was 8 for our formula and 3.5 for the commercial one, on a scale of 1-10 (P < 0.05). Due to its nutritional, sensorial and rheological properties, [F.sub.10]E could be used as a protein source in infant enteral formulas.