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Vitamin A deficiency is associated with increased morbidity and mortality from diarrheal disease, measles, and malaria. It has been proposed that vitamin A supplementation could be linked with childhood immunization programs to improve child health. We conducted a randomized, doubleblind, placebo-controlled clinical trial to evaluate the impact of linking vitamin A supplementation with the Expanded Programme on Immunization on morbidity and child growth. In West Java, Indonesia, 467 six-week-old infants were randomized to receive 7.5 mg retinol equivalent (RE), 15 mg RE, or placebo with childhood immunization contacts at 6, 10, and 14 wks and 9 mo of age. Child growth was assessed through anthropometry, and morbidity histories were obtained. Vitamin A supplementation had no apparent impact upon linear or ponderal growth or infectious disease morbidity in the first 15 mo of age when integrated with the Expanded Programme on Immunization.

Conclusion : Although improving vitamin A nutriture is of general importance in reducing diarrheal and measles morbidity and mortality in developing countries, this clinical trial showed no apparent benefit of vitamin A capsules for infant health when given through childhood immunization programs.  相似文献   
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BACKGROUND: This study compares the impact of the Texas Public School Nutrition Policy on lunch consumption of low‐ and middle‐income students in sixth through eighth grades. METHODS: Students in 1 middle socioeconomic status (SES) and 1 low SES school completed lunch food records before (2001/2002) and after (2005/2006) implementation of the Texas policy. Students recorded amount and source of foods/beverages consumed. Two‐way analyses of variance with year and school SES as factors were performed to compare consumption by school SES before and after implementation of the Texas policy. RESULTS: Regardless of year, the low SES group consumed less fat, sweetened beverages, and candy and more vitamin C and calcium than the middle SES group. There were more significant improvements in dietary patterns for the middle SES school students post‐policy, particularly from the National School Lunch Program (NSLP) meal. The middle SES school students reported significantly higher percentages of less healthy items from home post‐policy. CONCLUSIONS: Overall, low SES school students consumed more healthy lunches at school compared with middle SES school students, and the Texas policy improved middle SES school student dietary intakes. Whether the dietary behaviors in school influence dietary intake for the entire day is unknown.  相似文献   
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Objective To examine the relationships between psychosocial characteristics and change in exercise and food intake of women during the first year postpartum.

Design A prospective cohort study following women from pregnancy until 1 year postpartum. Psychosocial variables, change in food intake, and exercise frequency were assessed using anonymous mailed questionnaires during pregnancy and at 1 year postpartum. Sociodemographic and anthropometric information was obtained from the medical record.

Subjects/setting Six hundred twenty-two women who enrolled for prenatal care in the Bassett Healthcare system between November 7, 1994, and November 15, 1996, and who met the eligibility criteria. The attrition rate for completing the questionnaire at 1 year postpartum was 20%.

Statistical analyses performed Multivariate linear regression with exercise frequency at 1 year postpartum and change in food intake during the second 6 months postpartum as the dependent variables and psychosocial factors assessed at 1 year postpartum as the independent variables, controlling for sociodemographic variables, body mass index, and gestational weight gain.

Results Higher exercise self-efficacy and having the intention to exercise were associated with more frequent exercise at 1 year postpartum in the multivariate regression analysis (r2=20%). Food intake self-efficacy, body satisfaction, weight gain acceptance, and drive for thinness were all significant in the multivariate analysis (r2=7%) and higher scores on these variables were associated with reductions in food intake.

Applications/conclusions Interventions that aim to help women get regular exercise and make appropriate reductions in food intake during the postpartum period should focus on self-efficacy specific to the targeted behaviors. For example, dietitians may strengthen exercise self-efficacy by providing postpartum women with mastery experiences of setting realistic exercise goals. Likewise, dietitians can focus on food intake self-efficacy by modeling strategies that women can use to avoid overeating in stressful situations. J Am Diet Assoc. 2001;101:1430-1437.  相似文献   

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