The American journal of clinical nutrition最新文献

{"title":"Zinc supplementation might potentiate the effect of vitamin A in restoring night vision in pregnant Nepalese women.","authors":"P. Christian, S. Khatry, S. Yamini, R. Stallings, S. LeClerq, S. Shrestha, E. Pradhan, K. West","doi":"10.1093/AJCN/73.6.1045","DOIUrl":"https://doi.org/10.1093/AJCN/73.6.1045","url":null,"abstract":"BACKGROUND\u0000Zinc deficiency may result in abnormal dark adaptation or night blindness, a symptom primarily of vitamin A deficiency. During a placebo-controlled trial in Nepal, weekly vitamin A supplementation of women reduced but failed to eliminate the incidence of night blindness during pregnancy, suggesting a role for zinc.\u0000\u0000\u0000OBJECTIVE\u0000The study examined the efficacy of daily zinc supplementation in restoring night vision of pregnant women who developed night blindness while routinely receiving either vitamin A, beta-carotene, or placebo in a field trial.\u0000\u0000\u0000DESIGN\u0000Women (n = 202) who reported to be night blind during pregnancy were randomly assigned in a double-blind manner, stratified on vitamin A, beta-carotene, or placebo receipt, to receive 25 mg Zn or placebo daily for 3 wk. Thus, the 6 groups studied were as follows: beta-carotene + zinc, beta-carotene alone, vitamin A + zinc, vitamin A alone (vitamin A + placebo), zinc alone (zinc + placebo), and placebo (2 placebos: one for the vitamin A or beta-carotene study and one for the zinc study). Women underwent a clinic-based assessment that included pupillary threshold testing and phlebotomy before and after supplementation. Supplement use and daily history of night blindness were obtained at home twice every week.\u0000\u0000\u0000RESULTS\u0000Zinc treatment increased serum zinc concentrations, but alone (zinc alone group), failed to restore night vision or to improve dark adaptation. However, women in the vitamin A + zinc group who had baseline serum zinc concentrations <9.9 micromol/L were 4 times more likely to have their night vision restored (95% CI: 1.1, 17.3) than were women in the placebo group and tended to have a small improvement in pupillary threshold scores (by 0.21 log candela/m2; P = 0.09).\u0000\u0000\u0000CONCLUSION\u0000These data suggest that zinc potentiated the effect of vitamin A in restoring night vision among night-blind pregnant women with low initial serum zinc concentrations.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"187 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115943924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial modulation of innate defense: goblet cells and the intestinal mucus layer.","authors":"B. Deplancke, H. Gaskins","doi":"10.1093/AJCN/73.6.1131S","DOIUrl":"https://doi.org/10.1093/AJCN/73.6.1131S","url":null,"abstract":"The gastrointestinal epithelium is covered by a protective mucus gel composed predominantly of mucin glycoproteins that are synthesized and secreted by goblet cells. Changes in goblet cell functions and in the chemical composition of intestinal mucus are detected in response to a broad range of luminal insults, including alterations of the normal microbiota. However, the regulatory networks that mediate goblet cell responses to intestinal insults are poorly defined. The present review summarizes the results of developmental, gnotobiotic, and in vitro studies that showed alterations in mucin gene expression, mucus composition, or mucus secretion in response to intestinal microbes or host-derived inflammatory mediators. The dynamic nature of the mucus layer is shown. Available data indicate that intestinal microbes may affect goblet cell dynamics and the mucus layer directly via the local release of bioactive factors or indirectly via activation of host immune cells. A precise definition of the regulatory networks that interface with goblet cells may have broad biomedical applications because mucus alterations appear to characterize most diseases of mucosal tissues.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124649924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probiotics: future directions.","authors":"J. Vanderhoof","doi":"10.1093/AJCN/73.6.1152S","DOIUrl":"https://doi.org/10.1093/AJCN/73.6.1152S","url":null,"abstract":"Clinical studies have shown that certain probiotics may be useful in treating a variety of diarrheal disorders, including rotavirus diarrhea, antibiotic-associated diarrhea, Clostridium difficile diarrhea, and traveler's diarrhea. New data suggest that probiotics might be useful in controlling inflammatory diseases, treating and preventing allergic diseases, preventing cancer, and stimulating the immune system, which may reduce the incidence of respiratory disease. Different modes of administering probiotics are currently being investigated, which may ultimately lead to the widespread use of probiotics in functional foods. It is important that such practices be directed by carefully controlled clinical studies published in peer-reviewed journals.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126824827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Critique of the requirement for vitamin E.","authors":"M. Horwitt","doi":"10.1093/AJCN/73.6.1003","DOIUrl":"https://doi.org/10.1093/AJCN/73.6.1003","url":null,"abstract":"The Food and Nutrition Board of the Institute of Medicine recently published a comprehensive evaluation of antioxidants in human diets that includes dietary reference intakes for vitamin E. The new dietary reference intake is 15 mg (35 mol)/d for adults, which is 50% greater than the generous allowance in the 10th edition of Recommended Dietary Allowances published in 1989. Much of the data interpreted in these publications came from studies sponsored by the Committee of Nutritional Studies at Elgin State Hospital (Elgin, IL) of an earlier Food and Nutrition BOARD: The 50% increase in the recommended dietary allowances for vitamin E is not supported by any new data. It is possible that the publication of the Institute of Medicine did not take into consideration the effects of the oxidized lipids in the diets used to promote the development of vitamin E deficiency. If lipids, oxidized to remove tocopherols, had not been a part of the experimental diets, the minimum requirement for vitamin E would have been too small for possible evaluation. Studies on the different effects of saturated and oxidized lipids in the production of encephalomalacia in chicks and muscular dystrophy in rats are reviewed. The tolerable upper intake level of vitamin E supplementation is reported to be 1000 mg/d. It is possible that the universal consumption of aspirin may not have been taken into consideration when this level was determined. Vitamin E plus aspirin may increase the tendency to hemorrhage, which makes a lower upper intake level worth consideration.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127958773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chronic administration of pharmacologic doses of vitamin E improves the cardiac autonomic nervous system in patients with type 2 diabetes.","authors":"D. Manzella, M. Barbieri, E. Ragno, G. Paolisso","doi":"10.1093/AJCN/73.6.1052","DOIUrl":"https://doi.org/10.1093/AJCN/73.6.1052","url":null,"abstract":"BACKGROUND\u0000Type 2 diabetes is associated with elevated oxidative stress and declines in antioxidant defense. The disease is also characterized by an imbalance in the ratio of cardiac sympathetic to parasympathetic tone. Antioxidants, vitamin E in particular, may have beneficial effects on the cardiac autonomic nervous system through a decline in oxidative stress.\u0000\u0000\u0000OBJECTIVE\u0000We investigated the possible effects of vitamin E on the cardiac autonomic nervous system, as assessed by analysis of heart rate variability, in patients with type 2 diabetes and cardiac autonomic neuropathy.\u0000\u0000\u0000DESIGN\u0000In a double-blind randomized controlled trial, 50 patients with type 2 diabetes were assigned to treatment with vitamin E (600 mg/d) or placebo for 4 mo.\u0000\u0000\u0000RESULTS\u0000The anthropometric characteristics of the patients remained unchanged throughout the study. Chronic vitamin E administration was associated with decreases in concentrations of glycated hemoglobin (P < 0.05), plasma insulin (P < 0.05), norepinephrine (P < 0.03), and epinephrine (P < 0.02); a lower homeostasis model assessment index (P < 0.05); and improved indexes of oxidative stress. Furthermore, vitamin E administration was associated with increases in the R-R interval (P < 0.05), total power (P < 0.05), and the high-frequency component of heart rate variability (HF; P < 0.05) and decreases in the low-frequency component (LF; P < 0.05) and the ratio of LF to HF (P < 0.05). Finally, change in the plasma vitamin E concentration was correlated with change in the LF-HF ratio (r = -0.43, P < 0.04) independently of changes in the homeostasis model assessment index and plasma catecholamines concentrations.\u0000\u0000\u0000CONCLUSIONS\u0000Chronic vitamin E administration improves the ratio of cardiac sympathetic to parasympathetic tone in patients with type 2 diabetes. Such an effect might be mediated by a decline in oxidative stress.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120548553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Do trans fatty acids increase the incidence of type 2 diabetes?","authors":"M. Clandinin, M. Wilke","doi":"10.1093/AJCN/73.6.1001","DOIUrl":"https://doi.org/10.1093/AJCN/73.6.1001","url":null,"abstract":"","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127640202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of body fat in fatter and leaner 10-y-old African American and white children: the Baton Rouge Children's Study.","authors":"G. Bray, J. DeLany, D. Harsha, J. Volaufova, C. Champagne","doi":"10.1093/AJCN/73.4.687","DOIUrl":"https://doi.org/10.1093/AJCN/73.4.687","url":null,"abstract":"BACKGROUND\u0000Only a few published studies in children used several methods to compare body fat in large groups of fatter and leaner multiethnic children. We hypothesized that the preferred methods of determining body fat may differ in children with larger compared with smaller amounts of body fat, in boys compared with girls, and in African Americans compared with whites.\u0000\u0000\u0000OBJECTIVE\u0000Our objective was to evaluate several methods of predicting body fat in 10-12-y-old white and African American boys and girls.\u0000\u0000\u0000DESIGN\u0000The body fat of 129 African American and white boys and girls aged 10-12 y, distributed equally by sex and race, was measured with use of dual-energy X-ray absorptiometry (DXA), underwater weighing (densitometry), isotope dilution (H(2)18O), bioelectrical impedance, skinfold thicknesses, corporal diameters, and circumferences.\u0000\u0000\u0000RESULTS\u0000With use of DXA as the criterion variable, body fat was bimodally distributed in the boys and skewed to higher values in the girls. Biceps skinfold thickness had the highest predictive value of any single skinfold thickness compared with DXA fat. All formulas for estimating body fat from skinfold thicknesses, body density, or impedance performed better in the children in the upper one-half of the fat distribution (the fatter children) than in those in the lower one-half (the leaner children). Body mass index was highly correlated with body fat (R2 = 0.77); there was a good correlation for the fatter children (R2 = 0.66) and no correlation for the leaner children (R2 = 0.09). The hydration of the fat-free mass was significantly higher in the fatter children than in the leaner ones (79.2% compared with 76.7%).\u0000\u0000\u0000CONCLUSIONS\u0000These data are consistent with the hypothesis that all methods of estimating body fat work better in children with larger amounts of body fat. The best formulas use skinfold thicknesses, bioelectrical impedance, and a 4-compartment model.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124474378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Moderate dietary fat consumption as a risk factor for ischemic heart disease in a population with a low fat intake: a case-control study in Korean men.","authors":"I. Suh, K. W. Oh, K. H. Lee, B. Psaty, C. Nam, S. I. Kim, H. Kang, S. Y. Cho, W. Shim","doi":"10.1093/AJCN/73.4.722","DOIUrl":"https://doi.org/10.1093/AJCN/73.4.722","url":null,"abstract":"BACKGROUND\u0000Dietary fat intake is associated with the incidence of ischemic heart disease (IHD) in Western countries. In populations in which both the average dietary fat consumption and the incidence of IHD are lower than in Western countries, the association of dietary fat intake with IHD incidence remains unknown.\u0000\u0000\u0000OBJECTIVE\u0000We conducted a case-control study to examine the association of dietary fat with IHD incidence in Korean men.\u0000\u0000\u0000DESIGN\u0000The case group consisted of 108 patients with electrocardiogram-confirmed myocardial infarction or angiographically confirmed (> or =50% stenosis) IHD who were admitted to a university teaching hospital in Seoul, Republic of Korea. The controls were 142 age-matched patients admitted to the departments of ophthalmology and orthopedic surgery at the same hospital. Dietary fat intake was assessed by a nutritionist using a semiquantitative food-frequency questionnaire. Body mass index (BMI), cigarette use, alcohol intake, exercise, and history of disease were determined during an interview and examination.\u0000\u0000\u0000RESULTS\u0000In a univariate analysis, the mean percentages of energy from total fat, saturated fatty acids, and monounsaturated fatty acids were significantly higher in the cases than in the controls. BMI, smoking, and a history of hypertension were associated with the occurrence of IHD. In multiple logistic analyses, total fat intake was a significant risk factor (odds ratio: 1.08 for 1% of energy intake; 95% CI: 1.02, 1.14) after adjustment for BMI and smoking.\u0000\u0000\u0000CONCLUSION\u0000In a population with a relatively low fat intake (19% of energy intake), a moderate increase in total fat intake may be a risk factor for IHD.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"119287111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beta-oxidation of linoleate in obese men undergoing weight loss.","authors":"S. Cunnane, R. Ross, J. L. Bannister, D. Jenkins","doi":"10.1093/AJCN/73.4.709","DOIUrl":"https://doi.org/10.1093/AJCN/73.4.709","url":null,"abstract":"BACKGROUND\u0000In animals, the whole-body content and accumulation of linoleate can be measured and compared with its intake to determine linoleate beta-oxidation. This method can also provide quantitative information about the beta-oxidation of linoleate in humans.\u0000\u0000\u0000OBJECTIVES\u0000The objectives of the study were to 1) use the wholebody fatty acid balance method to quantify whole-body concentrations of linoleate in humans, 2) estimate the distribution of linoleate between adipose and lean tissue, and 3) assess the effect of weight loss on linoleate stores and beta-oxidation in obese humans.\u0000\u0000\u0000DESIGN\u0000Nine healthy obese men underwent supervised weight loss for 112 d (16 wk). Magnetic resonance imaging data and fatty acid profiles from fat biopsies were both used to determine linoleate stores in adipose and lean tissue and in the whole body. Linoleate beta-oxidation was calculated as intake - (accumulation + excretion).\u0000\u0000\u0000RESULTS\u0000Mean weight loss was 13 kg and linoleate intake was 24 +/- 6 mmol/d over the study period. Whole-body loss of linoleate was 37 +/- 18 mmol/d, or 28% of the level before weight loss. Combining the intake and whole-body loss of linoleate resulted in linoleate beta-oxidation exceeding intake by 2.5-fold during the weight-loss period.\u0000\u0000\u0000CONCLUSIONS\u0000All dietary linoleate is beta-oxidized and at least an equivalent amount of linoleate is lost from the body during moderate weight loss in obese men. The method studied permits the assessment of long-term changes in linoleate homeostasis in obese humans and may be useful in determining the risk of linoleate deficiency in other conditions.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114594028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Essential fatty acid composition of plasma phospholipids and birth weight: a study in term neonates.","authors":"P. Rump, R. Mensink, A. Kester, G. Hornstra","doi":"10.1093/AJCN/73.4.797","DOIUrl":"https://doi.org/10.1093/AJCN/73.4.797","url":null,"abstract":"BACKGROUND\u0000Essential fatty acids (EFAs) in umbilical cord blood samples are associated with attained birth weight in premature infants and low-birth-weight neonates.\u0000\u0000\u0000OBJECTIVE\u0000The objective was to investigate relations between the EFA composition of cord and maternal plasma phospholipids and birth weight in term neonates.\u0000\u0000\u0000DESIGN\u0000This was a cross-sectional study in 627 singletons born at term. The plasma phospholipid EFA composition of the mothers was determined by gas-liquid chromatography at study entry (< or = 16 wk gestation), at delivery, and in cord plasma at birth. Birth weights were normalized to SD scores.\u0000\u0000\u0000RESULTS\u0000In cord plasma, the dihomo-gamma-linolenic acid concentration was positively related to weight SD scores. Both arachidonic acid (AA) and docosahexaenoic acid (DHA) were negatively related to weight SD scores. EFA-status indicators showed similar negative associations, whereas eicosatrienoic acid concentrations were positively related to neonatal size. In maternal plasma, proportions of n-3 long-chain polyenes (LCPs) and n-6 LCPs decreased during pregnancy. Larger decreases in AA, DHA, n-3 LCP, and n-6 LCP fractions were observed in mothers of heavier babies. Higher concentrations of LCPs in maternal plasma were, however, not related to a larger infant size at birth.\u0000\u0000\u0000CONCLUSIONS\u0000A lower biochemical EFA status in umbilical cord plasma and a larger decrease in maternal plasma LCP concentrations are associated with a higher weight-for-gestational-age at birth in term neonates. Our findings do not support a growth-stimulating effect of AA or DHA; however, they do suggest that maternal-to-fetal transfer of EFAs might be a limiting factor in determining neonatal EFA status.","PeriodicalId":315016,"journal":{"name":"The American journal of clinical nutrition","volume":"8 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126076749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}