RESUMO
BACKGROUND: In acute illnesses, plasma glucose levels are often increased and generally parallel the severity of stress. Hyperglycemia caused by reduced insulin sensitivity and reduced insulin secretion is associated with increased susceptibility to infections. Maintaining blood glucose levels at or below 110 mg/dl reduces morbidity and mortality in critically ill patients. AIM: To measure the glucose and insulin responses of four commercially available enteral formulas compared with a standard meal reference product. MATERIAL AND METHODS: The glycemic index (GI) and the insulin index (II) were determined in a randomized, cross over protocol in 38 healthy volunteers between 18 and 46 years of age. Each subject underwent five tests: three with the standard meal (bread) and two with the study products. The enteral formulas were Clinutren HPR (whole protein of high protein value), Crucial (casein peptide based formula), Peptamen, (whey peptide based formula), Glytrol (formula for diabetics with whole protein with fiber). Each study product was evaluated 10 times. RESULTS: The diabetic formula and the high protein energy dense formulas induced a significantly lower GI (p <0.02) compared with the standard meal. The GI response did not appear to be due to enhanced insulin secretion. The other tested formulas had lower GI than the standard meal, but in addition they exhibited increased II The whey based peptide formulation produced the highest insulin response (p <0.03). CONCLUSIONS: Both GI and II are related to the concentration, form and type of protein contained in the enteral formula. The whey peptide formulation produced a low GI with the highest insulin index. Based on the low GI of these enteral products, all can be useful to provide nutritional support during metabolic stress, without adding an additional challenge to blood glucose management.
Assuntos
Glicemia/fisiologia , Nutrição Enteral , Alimentos Formulados/análise , Índice Glicêmico/fisiologia , Insulina/sangue , Adolescente , Adulto , Análise de Variância , Área Sob a Curva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/fisiologiaRESUMO
Background: In acute illnesses, plasma glucose levels are often increased and generally parallel the severity of stress. Hyperglycemia caused by reduced insulin sensitivity and reduced insulin secretion is associated with increased susceptibility to infections. Maintaining blood glucose levels at or below 110 mg/dl reduces morbidity and mortality in critically ill patients. Aim: To measure the glucose and insulin responses of four commercially available enteral formulas compared with a standard meal reference product. Material and Methods: The glycemic index (GI) and the insulin index (II) were determined in a randomized, cross over protocol in 38 healthy volunteers between 18 and 46 years of age. Each subject underwent five tests: three with the standard meal (bread) and two with the study products. The enteral formulas were Clinutren HPR (whole protein of high protein value), Crucial® (casein peptide based formula), Peptamen®, (whey peptide based formula), Glytrol® (formula for diabetics with whole protein with fiber). Each study product was evaluated 10 times. Results: The diabetic formula and the high protein energy dense formulas induced a significantly lower GI (p <0.02) compared with the standard meal. The GI response did not appear to be due to enhanced insulin secretion. The other tested formulas had lower GI than the standard meal, but in addition they exhibited increased II The whey based peptide formulation produced the highest insulin response (p <0.03). Conclusions: Both GI and II are related to the concentration, form and type of protein contained in the enteral formula. The whey peptide formulation produced a low GI with the highest insulin index. Based on the low GI of these enteral products, all can be useful to provide nutritional support during metabolic stress, without adding an additional challenge to blood glucose management.
Assuntos
Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Glicemia/fisiologia , Nutrição Enteral , Alimentos Formulados/análise , Índice Glicêmico/fisiologia , Insulina/sangue , Análise de Variância , Área Sob a Curva , Período Pós-Prandial/fisiologiaRESUMO
OBJECTIVE: To study the effects of a special nutritional supplement on bone mineral density and bone turnover markers in Chilean elderly subjects with femoral osteoporosis. SETTING: Public primary health care clinics in Chile. SUBJECTS: Free living elderly subjects with femoral osteoporosis. INTERVENTIONS: Subjects were randomized to receive the usual nutritional supplement provided by the Chilean Ministry of Health or a special nutritional supplement providing, among other nutrients, 90 mg isoflavones, 800 mg calcium, 400 IU vitamin D, 60 ug vitamin K and 31 g proteins per day. MEASURES OF OUTCOME: At baseline, and after six and twelve months of supplementation, body composition, bone mineral density, serum 25 OH vitamin D, intact parathyroid hormone (iPTH), osteocalcin, decarboxylated osteocalcin, urinary aminoterminal telopeptide of type I collagen (NTX), deoxypyridoline cross links (Dpd) and equol were measured. Every month, urinary daidzein was measured in a morning urine sample. RESULTS: No differences between treatment groups were observed in body composition or bone mineral density changes. The group receiving the special supplement had a significant increase in serum 25 OH vitamin D and a significant decrease in serum iPTH and decarboxylated osteocalcin. No association between daidzein or equol excretion and changes in bone mineralization was observed. CONCLUSIONS: A special supplement delivered to elderly subjects with osteoporosis improved serum vitamin D and reduced serum iPTH and undercarboxylated osteocalcin levels but did not affect BMD.
Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Osteoporose/tratamento farmacológico , Idoso , Análise de Variância , Cálcio/metabolismo , Cálcio/uso terapêutico , Chile , Suplementos Nutricionais , Feminino , Humanos , Isoflavonas/metabolismo , Isoflavonas/uso terapêutico , Masculino , Osteocalcina/sangue , Osteoporose/sangue , Hormônio Paratireóideo/sangue , Estudos Prospectivos , Resultado do Tratamento , Vitamina D/metabolismo , Vitamina D/uso terapêuticoRESUMO
BACKGROUND: Immune response is impaired in the elderly. Our aim was to study the effects of a special nutritional formula on the immune response and response to influenza and pneumococcal vaccination in elderly subjects. METHODS: Sixty healthy subjects aged > or = 70 years, with a Mini Mental score > or = 22 were studied. Half of the subjects received a special nutritional formula (in addition to the regular diet) providing, among other nutrients, 480 kcal, 31 g proteins, 120 IU vitamin E, 3.8 microg vitamin B12, 400 microg folic acid, 10(9) cfu Lactobacillus paracasei (NCC 2461), and 6 g of fructo-oligosaccharides. At 4 months of follow-up, subjects were vaccinated against influenza and pneumococcus. Lymphokine production by mononuclear cells (PBMC), lymphocyte subpopulations, and natural killer cell (NK) activity were measured at baseline and 4 months of follow-up (before vaccination). Antibodies against influenza and pneumococcal antigens and flu-stimulated production of interferon gamma and interleukin-2 by PBMC were measured at 4 and 6 months. Skin response to 7 recall antigens and body composition were assessed at baseline and at 4 and 12 months. All infections occurring during the study period were recorded. RESULTS: NK activity increased in supplemented subjects and decreased in nonsupplemented individuals. Interleukin-2 production by PBMC and the proportion of T cells with NK activity decreased in controls and did not change in supplemented subjects. Supplemented subjects reported less infections than nonsupplemented individuals (in 13% and 22% of scheduled visits, respectively; p = .02). CONCLUSIONS: This nutritional supplement increased innate immunity and protection against infections in elderly people.
Assuntos
Envelhecimento/imunologia , Citocinas/biossíntese , Alimentos Formulados , Imunidade Inata/imunologia , Vacinas contra Influenza/imunologia , Vacinas Pneumocócicas/imunologia , Idoso , Formação de Anticorpos/imunologia , Chile , Suplementos Nutricionais , Feminino , Seguimentos , Humanos , Imunidade Inata/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/imunologia , Subpopulações de Linfócitos , MasculinoRESUMO
OBJECTIVE: We studied alterations of circulating antioxidant nutrients in patients with classic dengue fever in the tropical lowlands of Guatemala. METHODS: In nine patients with dengue fever and 12 healthy Guatemalan control subjects, we assessed plasma concentrations of retinol, alpha-tocopherol, beta-carotene, glutathione, taurine, thiobarbituric acid-reactive species, and total antioxidant status. Control subjects were assessed twice within 48 h to account for day-to-day variations. Febrile patients with dengue fever were examined on the day of admission to the hospital, at discharge after defervescence (approximately 5 d after admission), and 7 d thereafter. RESULTS: In patients with dengue fever, increases in plasma concentrations of retinol and beta-carotene were seen, whereas decreases were observed for glutathione and total antioxidant status. As compared with the reference group, patients with dengue fever had lower retinol concentrations in the acute phase of the disease and lower glutathione concentrations 7 d after discharge. Further, thiobarbituric acid-reactive species levels were higher in the dengue fever patients as analyzed by unpaired t test. CONCLUSION: Using dengue fever as a model for the metabolic response to an acute, self-limited tropical viral infection, the present findings suggest slight turbulence of the antioxidant system that may be a response to or a consequence of the viral inflammatory process.