Added thermogenic and satiety effects of a mixed nutrient vs a sugar-only beverage.

OBJECTIVE: To examine the effects of a sugar-only (SO) beverage vs one containing a mixed-nutrient (MN) composition on energy expenditure and feelings of hunger and satiety. HYPOTHESIS: A beverage containing a mixed macronutrient composition will lead to greater thermic effect of food and feelings of fullness than an isocaloric beverage containing only sugar. RESEARCH METHODS AND PROCEDURES: Adults were randomly assigned to receive a 2510 kJ (600 kcal) SO liquid formula followed by an isovolumic, isoenergetic, MN liquid formula with an energy distribution of 17% protein, 67% carbohydrates as sucrose and corn syrup solids, and 16% fat, or vice versa, in a crossover design. The carbohydrate source in the two beverages was identical: 1:1 ratio of sucrose and corn syrup solids (25 dextrose equivalents). The thermic response was calculated as the 7 h deviation from resting metabolic rate (RMR). Subjects provided hunger/satiety ratings and other related information by visual analog scales at regular intervals throughout the study period. RESULTS: In all, 20 subjects completed the protocol; one was removed from the thermic effect analysis due to discrepant RMRs. Following beverage ingestion, SO and MN liquid meals produced 7 h thermic effects of (X+/-s.e.m.) 274.1+/-27.6 kJ (65.5+/-6.6 kcal) and 372.0+/-33.9 kJ (88.9+/-8.1 kcal), respectively, resulting in a significant (P<0.01) difference between meals (Delta=97.9+/-35.1 kJ [23.4+/-8.4 kcal]). Analysis of satiety ratings using area under the curve analysis showed greater feelings of satiety (P<0.05) with MN compared to SO consumption. Also, subjects felt that they could eat less (P<0.05) after consumption of the MN vs SO beverage. DISCUSSION: In comparison to MN beverages, SO beverages are associated with a relatively high-energy retention without accompanying subjective hunger/fullness compensations, suggesting a basis for their role in long-term unintentional weight gain in healthy adults.

A randomized controlled trial evaluating nutrition counseling with or without oral supplementation in malnourished HIV-infected patients.

OBJECTIVE: To evaluate the effects of nutrition counseling with or without oral supplementation in malnourished patients infected with the human immunodeficiency virus (HIV). DESIGN: Randomized controlled trial. SUBJECTS: HIV-infected men (n=118) who were less than 90% of usual weight for height or who had lost more than 10% of body weight. INTERVENTION: Nutrition counseling alone (control group) vs nutrition counseling plus enteral supplementation (supplement group) for 6 weeks. All patients were instructed to consume a diet that exceeded estimated total energy expenditure by 960 kcal/day. MAIN OUTCOME MEASURES: Weight, skinfold thickness, fat-free mass, grip strength, quality of life, and cognitive function (Buschke test). STATISTICAL ANALYSES: Differences in baseline variables and outcomes were evaluated using analysis of variance or the Wilcoxon rank sum test. RESULTS: Ninety-nine men completed at least 4 weeks of treatment, 49 in the supplement group and 50 in the control group. Half the patients in each treatment group achieved at least 80% of their energy target. No differences in weight, skinfold thickness measurements, or quality of life were observed. Compared with the control group, the supplement group had larger increases in fat-free mass and grip strength, although the differences did not reach statistical significance. APPLICATIONS: In the short term, nutrition counseling with or without oral supplementation can achieve a substantial increase in energy intake in about 50% of malnourished HIV-infected patients. Although further study is needed to evaluate long-term effects, these findings suggest that nutrition counseling has an important role in the management of malnourished HIV-infected patients.

Decreased fat and nitrogen losses in patients with AIDS receiving medium-chain-triglyceride-enriched formula vs those receiving long-chain-triglyceride-containing formula.

OBJECTIVE: The purpose of this study was to compare two enteral formulas, differing only in fat source, for product acceptance, tolerance, and effect on fat malabsorption and nutritional status in subjects with acquired immune deficiency syndrome (AIDS). DESIGN: The double-blind, randomized 15-day trial was divided into a 3-day period in which solid food was consumed followed by a 12-day experimental period in which liquid formulas were consumed. SETTING/SUBJECTS: Twenty-three men and one woman with AIDS and fat malabsorption completed the study. The study was conducted in the General Clinical Research Center, University of Alabama Hospital, University of Alabama at Birmingham. Laboratory assays were performed in the Department of Nutrition Sciences. INTERVENTIONS: After 3 days of consuming a controlled, solid food diet containing 100 g fat per day from mixed sources to document fat malabsorption, subjects were randomly assigned to one of two groups. Each group received a liquid formula containing 35% of energy as fat for 12 days. One group received a formula containing 85% medium-chain triglycerides (MCTs) and the control group received a formula containing 100% long-chain triglycerides. MAIN OUTCOME MEASURES: Determinations included stool number, consistency, weight, and fat and nitrogen content; urine nitrogen and creatinine levels; and body weight. STATISTICAL ANALYSIS PERFORMED: Subject demographic and other baseline characteristics were compared using two-sample t tests; stool and urine assessments were compared between groups at the initial experimental period using two-sample t tests; changes from initial to final experimental periods were assessed by means of analysis of covariance; changes in pooled intake, body weight, and the number and consistency of bowel movements were also assessed using analysis of covariance. All statistical tests were two-tailed and considered significant at P < .05. RESULTS: Within-group comparisons indicated that subjects fed the MCT formula showed significantly decreased stool fat and stool nitrogen content (P = .01 and P = .03, respectively) and increased fat absorption (P = .03), whereas those fed the control formula did not. Differences in stool fat between the groups were not statistically significant. However, the difference in fat absorption from the initial to final formula period was significant (P = .04). Subjects consuming the MCT formula also tended to have a decreased number of bowel movements and abdominal symptoms, whereas subjects fed the control formula showed no improvement. All subjects maintained their body weights. APPLICATIONS: There may be advantages to using an MCT-based formula in the treatment of AIDS-associated malabsorption.

Visual acuity and blood lipids in term infants fed human milk or formulae.

This multicenter, parallel group study determined plasma phospholipid and red blood cell (RBC) phosphatidylcholine and phosphatidylethanolamine fatty acids, plasma cholesterol, apo A-1 and B, growth and visual acuity (using the acuity card procedure) in term infants fed from birth to 90 d of age with formula containing palm-olein, high oleic sunflower, coconut and soy oil (22.2% 16:0, 36.2% 18:1, 18% 18:2n-6, 1.9% 18:3n-3) (n = 59) or coconut and soy oil (10.3% 16:0 18:6% 18:1, 34.2% 18:2n-6, 4.7% 18:3n-3) (n = 57) or breast-fed (n = 56) with no formula supplementation. Different centers in North America were included to overcome potential bias due to differences in n-6 or n-3 fatty acids at birth or in breast-fed infants that might occur in a single-site study. Plasma and RBC phospholipid docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6), cholesterol and apo B were significantly lower in the formula- than breast-fed infants. There were no differences in looking acuity or growth among the breast-fed and formula-fed infants. No significant relations were found between DHA and looking acuity, or AA and growth within or among any of the infant groups. This study provides no evidence to suggest the formula provided inadequate n-6 or n-3 fatty acids for growth and looking acuity for the first 3 mon after birth.

A medium chain triglyceride-based diet in patients with HIV and chronic diarrhea reduces diarrhea and malabsorption: a prospective, controlled trial.

Our objective was to determine whether a medium-chained triglyceride (MCT)-based diet, compared to a long-chain triglyceride (LCT)-based diet, conveys a beneficial effect on diarrhea and fat malabsorption in human immunodeficiency virus (HIV)-infected individuals with chronic diarrhea and weight loss. A secondary objective was to evaluate the pathogens associated with the diarrhea and to evaluate whether the etiologic agent was a determinant of response to the nutritional intervention. Prospective, randomized double-blind comparative trial was conducted in 24 adult patients with HIV, diarrhea of greater than 4-wk duration, fat malabsorption, and loss of 10-20% of ideal body weight, these patients were recruited from our outpatient infectious disease clinic. Evaluations of diarrheal pathogens were made by complete stool examination, upper and lower endoscopy with quantitative culture, and biopsy. Body composition determinations, and measurements of fat, carbohydrate, and vitamin absorption pre- and postintervention. Patients were randomly assigned to one of two complete nutritional products with either medium- or long-chain triglyceride fat exclusively for 12 d followed by treatment of infectious pathogens. Ten patients were found to have Microsporidium and 9 patients had no identifiable pathogen. All patients responded to intervention with both nutritional products overall with 45% fewer stools, decreased stool fat and weight, and a significant increase in urine nitrogen. The group that received the MCT product demonstrated significantly decreased stool number (mean 4 to 2.5), stool fat (mean 14 to 5.4 g), and stool weight (mean 428 to 262 g) compared with baseline (P < 0.01 for all). Patients with both species of microsporidia and with pathogen negative diarrhea had good response. We found that HIV patients with diarrhea, regardless of etiology, and documented fat malabsorption may benefit symptomatically from a diet composed of an MCT-based liquid supplement.

Gastric emptying, pulmonary function, gas exchange, and respiratory quotient after feeding a moderate versus high fat enteral formula meal in chronic obstructive pulmonary disease patients.

High fat enteral formulas have been advocated for the nutritional support of chronic obstructive pulmonary disease (COPD) patients because dietary fat utilization under ideal conditions produces less CO2 per O2 consumed than carbohydrate. No data exist for these patients comparing the effects of a moderate fat vs. a high fat enteral formula on gastric emptying times (GE) and subsequent CO2 production (VCO2), oxygen consumption (VO2), respiratory quotient (RQ), and pulmonary function. Our double-blind crossover study compared these parameters after feeding a 355 mL (530 kcal) meal with either 41% fat calories (Respalor) or 55% fat calories (Pulmocare). Thirty-six COPD outpatients with a forced expiratory volume in 1 s (FEV1) < 60% of predicted were studied after an overnight fast. Gastric emptying half-time (GE t1/2) was measured using the 99MTc-radionuclide technique; VCO2, VO2, RQ, and other pulmonary functions were measured at 0, 30, 90, and 150 min postprandial using the Canopy Mode of the Deltatrac Metabolic Monitor and the Renaissance Spirometry System. We observed a significantly (p = 0.0001) longer GE t1/2 of the high fat meal when compared to the moderate fat meal (134.1 vs. 108.6 min) At 30 and 90, but not at 150 min postprandial, the VCO2 and VO2 for patients fed the moderate-fat formula were significantly (p = 0.05) higher than for those fed the high-fat formula; no differences were observed for the other pulmonary functions. Although RQ increased significantly (p = 0.01) after both meals, no differences between formulas were noted at all postprandial times tested. Compared to the high-fat meal, the moderate-fat meal significantly enhanced gastric emptying. The earlier rise in VCO2 and VO2 after the moderate-fat meal did not impact pulmonary function and reflected the earlier utilization of the moderate-fat meal. The fact that RQ was not different between the two meals at all postprandial times tested suggest that the higher rise in VCO2 and VO2 after the moderate-fat meal was most likely due to earlier gastric emptying of the moderate-fat meal rather than the difference of the fat-to-carbohydrate ratio between the two tested meals. The impact of these findings on long-term management of COPD patients awaits long-term prospective studies.

Fiber supplementation of enteral formulas: effects on the bioavailability of major nutrients and gastrointestinal tolerance.

Two fiber-supplemented enteral formulas were recently introduced for patient application, Susta II and Enrich (12.4-g and 38.5-g soy polysaccharide/2000 kcal, respectively). This investigation had a 3-fold purpose: to determine if and to what extent fiber-supplementation changes the chemical composition of stool relative to a fiber-free formula (Ensure); to establish the clinical tolerance of the two new formulas; and to quantify the effects of soy polysaccharide on nutrient bioavailability. The study was conducted in two consecutive phases: A (n = 6 subjects; random assignment to either Ensure or Susta II for 1-2 weeks followed by isocaloric cross-over to the alternate formula for an equal period of time) and B (n = 8 subjects evaluated as in phase A except Enrich replaced Ensure). Each balance week consisted of clinical/subjective monitoring, evaluation of stool composition (H2O and dry weight), apparent nutrient absorption (energy, fat, N, P, K, Ca, Mg, Zn, Na, and Cl), and metabolic balance (N, P, K, Ca, Mg, Na, and Cl). Relative to the fiber-free formula the two fiber-supplemented solutions produced increases in fecal N, fat, H2O, and minerals of variable magnitude; there were corresponding reductions in net absorption of organic compounds and minerals. The additional minerals added to the fiber-supplemented formulas and the minimal effects on N absorption preserved balance; the retention of N, P, K, Ca, Mg, Na, and Cl were similar for all three formulas. No adverse clinical effects of the fiber-supplemented formulas were noted.(ABSTRACT TRUNCATED AT 250 WORDS)

Free amino acid formula: nitrogen utilization and metabolic effects in normal subjects.

A previous study indicated increased urea production and low nitrogen (N) retention on a free amino acid elemental formula (FAA; Vivonex-HN). The limitations of this earlier study were: irregular nitrogen absorption in the malabsorption patients, high nitrogen intake, and failure to match FAA to control formula (hydrolyzed casein; CAS; Criticare-HN) with respect to kcal/nitrogen. A more critical test of FAA quality was sought in the current study. Four healthy males received the minimal daily nitrogen requirements (0.6 g protein/kg) from either FAA or CAS in a 10-day balance study; a second balance on the alternate formula followed. Maintenance energy, minerals, and vitamins were supplied in each period. The results indicated a higher apparent nitrogen absorption (p less than 0.05) from FAA relative to CAS in the first 5 days of the balance, although these differences were no longer present in the remaining 5 days of the period. Urinary total nitrogen increased on FAA, most of which could be accounted for by urea nitrogen; urinary creatinine nitrogen, ammonia nitrogen, and uric acid nitrogen were nearly identical between formulas. The unmeasured fraction of urinary nitrogen was markedly diminished on FAA while the urea nitrogen to total nitrogen ratio was significantly increased (p less than 0.05) compared to CAS. During the initial 5 days of study nitrogen balance was lower on FAA than on CAS and this difference became significant during the last 5 days of the period (mean +/- SD for FAA = -0.42 +/- 0.59 g/D vs CAS = 0.98 +/- 0.30 g/day, p less than 0.001). Hyperglycinemia was consistently present during FAA infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of elemental diet on albumin and urea synthesis: comparison with partially hydrolyzed protein diet.

Enhanced nitrogen utilization occurs when adults with gastrointestinal disease are fed partially hydrolyzed proteins instead of isonitrogenous, isocaloric crystalline amino acids. A controlled trial was conducted to determine if this difference was also seen in malnourished stressed cancer patients and to gain an understanding of the underlying mechanism. Sixteen malnourished patients with head and neck cancer were prospectively randomized to either crystalline amino acid-glucose (CAA-G) or partially hydrolyzed protein-glucose (PHP-G) diets. Patients were fed via an enteral tube for 10 days starting on the second postoperative day. Blood SMA-6 and amino acid levels were measured on Days 1 and 10. Daily calorie counts and fluid balance were obtained. Daily 24-hr urine and stools were analyzed for total N during the last 5 days of the study period. The daily positive N balance with both diets was the same (CAA-G = +7.8 +/- 0.8 vs PHP-G = +8.2 +/- 1.0 g; mean +/- SE) and 3-methylhistidine:creatinine ratio did not differ. Patients on PHP-G diet gained significantly more weight (+0.5 vs - 1.5 kg; P less than 0.01) and had significantly higher serum albumin (3.2 +/- 0.2 vs 2.8 +/- 0.1 g/dl; P = 0.5) by the end of the 10th study day. Weight changes were not due to fluid retention: serum Na+, K+, creatinine and mean fluid intake for the two groups remained the same during the study period. A significantly greater rise in BUN occurred on the CAA-G diet (from 9.2 +/- 1.7 to 15.4 +/- 1.4 mg/dl; P less than 0.05) while BUN remained unchanged on the PHP-G diet.(ABSTRACT TRUNCATED AT 250 WORDS)