膳食纤维在肠内营养中应用的系统评价

目的评价膳食纤维在临床肠内营养中对腹泻、感染及住院时间的影响。方法检索MEDLINE光盘数据库、EMBASE光盘数据库、Cochrane图书馆临床对照试验资料库、中国生物医学文献光盘数据库，查找有关膳食纤维在肠内营养应用中的随机对照试验，用RevMan4．1软件进行Meta-分析。结果7项随机对照试验共400例患者纳入研究。5篇文献报告了膳食纤维对腹泻的影响，合并分析显示差异无显著性，亚组分析发现对非危重患者可降低腹泻发生率。2篇文献报告了感染率和住院时间，合并分析显示膳食纤维缩短了住院时间，但尚不能肯定对降低感染率的价值。结论膳食纤维可改善非危重患者的腹泻，但尚缺乏证据说明对危重患者同样有效，也还不能证明有减少感染的作用，建议对膳食纤维在肠内营养中应用的价值作进一步研究。     

Dietary Fiber and Its Source Are Associated with Cardiovascular Risk Factors in Korean Adults

We examined the associations of dietary fiber and its source with cardiovascular risk factors in Korean adults. This cross-sectional study involved 16,792 adults from the 2013–2018 Korea National Health and Nutrition Examination Survey data. Dietary data were obtained using a 24 h recall method and used to evaluate intakes of total dietary fiber and its source and fruit consumption. Cardiovascular risk factors included obesity, abdominal obesity, metabolic syndrome, hypercholesterolemia, hypertension, and type 2 diabetes. Multiple logistic regression was used to examine the associations of dietary fiber and its source with cardiovascular risk factors by sex. Total fiber and fruit fiber intake in men were inversely associated with metabolic syndrome (Q5 vs. Q1: odds ratios (OR) = 0.69, 95% confidence intervals (CI) = 0.53–0.92 for total fiber; Q4 vs. Q1: OR = 0.76, 95% CI = 0.61–0.93 for fruit fiber). Among women, a higher intake of fruit fiber was related to a reduced prevalence of obesity (Q4 vs. Q1: OR = 0.85, p trend = 0.029) and abdominal obesity (Q4 vs. Q1: OR = 0.82, p trend = 0.026). Total fruit and whole fruit consumption was inversely associated with obesity, abdominal obesity, and metabolic syndrome in men and hypertension in women. The amount and sources of fiber are associated with metabolic diseases in Korean adults and should be considered in the context of overall dietary quality.     

Comparison of Indices of Carbohydrate Quality and Food Sources of Dietary Fiber on Longitudinal Changes in Waist Circumference in the Framingham Offspring Cohort

The long-term impact of carbohydrate quality on abdominal weight gain is not fully understood. We aimed to examine the prospective relation of a carbohydrate quality index (CQI; defined by four criteria: dietary fiber, glycemic index, whole grain-to-total grain ratio, and solid-to-total carbohydrate ratio), total, cereal grain, vegetable, and fruit fiber, carbohydrate-to-total fiber ratio, and carbohydrate-to-cereal fiber ratio with changes in waist circumference (WC). Subjects were middle-aged to older, mostly white, participants in the Framingham Offspring cohort (n = 3101 subjects), with mean baseline age 54.9 ± 0.2 years (mean ± SE) and body mass index (BMI) 27.2 ± 0.1 kg/m². Food frequency questionnaire (FFQ), health, and lifestyle data were collected approximately every four years over a median total follow-up of 18 years. Repeated measure mixed models were used to estimate adjusted mean change in WC per four-year interval across quartiles of carbohydrate variables. In the most adjusted model, a higher CQI was marginally associated with a smaller increase in WC (2.0 ± 0.1 vs. 2.4 ± 0.1 cm in highest vs. lowest quartile, p-trend = 0.04). Higher ratios of carbohydrate-to-fiber and carbohydrate-to-cereal fiber were associated with greater increases in WC per four-year interval (2.6 ± 0.1 vs. 2.0 ± 0.1 cm, p-trend < 0.001, and 2.5 ± 0.1 vs. 2.1 ± 0.1 cm in highest versus lowest categories, p-trend = 0.007, respectively); whereas higher intake of total fiber (1.8 ± 0.1 vs. 2.7 ± 0.1 cm, p-trend < 0.001), cereal fiber (2.0 ± 0.1 vs. 2.5 ± 0.1 cm, p-trend = 0.001), and fruit fiber (2.0 ± 0.1 vs. 2.7 ± 0.1 cm, p-trend < 0.001) were associated with smaller increases in WC compared to lower intakes. There was a significant interaction between total fiber and total carbohydrate (as % of total energy intake). After stratification, the association between fiber intake and change in WC was not maintained in the context of a high carbohydrate diet. Better carbohydrate quality, primarily higher fiber intake and lower carbohydrate-to-fiber ratios, may help attenuate increases in abdominal adiposity over time.     

Associations between Dietary Animal and Plant Protein Intake and Cardiometabolic Risk Factors—A Cross-Sectional Study in China Health and Nutrition Survey

Available data investigating the associations between dietary animal and plant protein intakes and cardiometabolic risk factors (CMRFs) among populations with habitual plant-based diets are heterogenous and limited in scope. The current study was to assess the associations between dietary animal and plant protein intakes and CMRFs, including lipid and lipoprotein profiles, glucose homeostasis biomarkers, low-grade chronic inflammatory biomarker and uric acid in Chinese adults. Data of 7886 apparently healthy adults were extracted from the China Health and Nutrition Survey 2009. Dietary protein (total, animal and plant) intakes were assessed with three consecutive 24 h dietary recalls, and CMRFs were measured with standard laboratory methods. Substituting 5% of energy intake from animal protein for carbohydrates was positively associated with total cholesterol, low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C) and uric acid (all p < 0.05). Substituting 5% of energy intake from plant protein for carbohydrates was inversely associated with non-HDL-C and LDL-C:HDL-C ratio, and positively associated with HDL-C and glycated hemoglobin (all p < 0.05). Some of these associations varied in subgroup analyses by BMI, sex, age or region. There were no significant associations between animal or plant protein intakes and high-sensitivity C-reactive protein. The public health implication of these findings requires further investigation.     

Changes in Quantity and Sources of Dietary Fiber from Adopting Healthy Low-Fat vs. Healthy Low-Carb Weight Loss Diets: Secondary Analysis of DIETFITS Weight Loss Diet Study

The daily intake of dietary fiber is well below the recommended levels in the US. The effect of adopting a low-fat vs. a low-carbohydrate weight loss diet on fiber intake is of interest but not well-documented, especially when both approaches promote high-quality food choices. The objective of this paper is to compare the quantity and sources of dietary fiber between a healthy low-fat (HLF) vs. healthy low-carbohydrate (HLC) diet group when consumed over 12 months in a weight loss diet study. In this secondary analysis of the Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) study, the amount and sources of dietary fiber were examined in generally healthy adults, 18–50 years of age, Body Mass Index (BMI) 28–40 kg/m², randomized to HLF or HLC for 12 months, who had available 24-h recalls at 0 (n = 609), 3 (n = 549), 6 (n = 491), and 12 (n = 449) months. The dietary intake was estimated by the Nutrition Data System for Research (NDS-R). The sources of fiber were determined for the major food groups. Significantly more total dietary fiber was consumed by HLF at every post-randomization time point, and, at 12 m, was 23.04 ± 9.43 g vs. 18.61 ± 8.12 g for HLF vs. HLC, respectively, p < 0.0001. In both diet groups at 12 months, the highest amount of dietary fiber came from non-starchy vegetables (4.13 ± 3.05 g and 5.13 ± 3.59 g). The other primary sources of fiber at 12 months for the HLF group were from whole grains (3.90 ± 3.13 g) and fruits (3.40 ± 2.87 g), and, for the HLC group, were from plant protein and fat sources, such as nuts and seeds, their butters, and avocados (2.64 ± 2.64 g). In the DIETFITS study, the difference in the total fiber intake for the HLF vs. HLC groups was more modest than expected. The HLC group consumed reasonably high amounts of fiber from high-protein and high fat plant-based sources.     

The Association of Dietary Fiber Intake in Three Meals with All-Cause and Disease-Specific Mortality among Adults: The U.S. National Health and Nutrition Examination Survey, 2003–2014

The timing of food intake can significantly alter the body’s metabolism of nutrient intake and affect the occurrence of chronic diseases. However, whether and how the intake time of dietary fiber could influence mortality risks is largely unknown. This study aims to reveal the association between total dietary fiber intake and fiber intake at different times with all-cause, cancer, and cardiovascular disease (CVD) mortality rates. A total of 31,164 adults who enrolled in the National Health and Nutrition Examination Survey from 2003 to 2014 are included in this study. Dietary fiber intake was measured using 2-day, 24 h dietary recall. The main exposures in this study were the intake of dietary fiber at breakfast, lunch, and dinner via regression analysis of the residual method. The main outcomes were the all-cause, cancer, and CVD mortality rates. Cox proportional hazards regression models were used to evaluate the survival relationship between dietary fiber intake at different times and mortality rates. Among the 31,164 adults, 2915 deaths, including 631 deaths due to cancer and 836 deaths due to CVD, were documented. Firstly, after adjusting for potential confounders, compared to the participants in the lowest quintile of total dietary fiber intake, the participants in the highest quintile of fiber intake had lower all-cause (HR = 0.686, 95% CI: 0.589–0.799, p for trend <0.001) and cancer (HR = 0.606, 95% CI: 0.446–0.824, p for trend = 0.015) mortality risks. Secondly, compared to the participants in the lowest quintile of dietary fiber intake at dinner, the participants in the highest quintile of fiber intake had lower all-cause (HR = 0.796, 95% CI: 0.668–0.949, p for trend = 0.009) and cancer (HR = 0.564, 95% CI: 0.388–0.822, p for trend = 0.005) mortality risks. Furthermore, equivalently replacing each standard deviation of dietary fiber consumed at breakfast with that at dinner was associated with lower cancer mortality risks (HR = 0.846, 95% CI: 0.747–0.958). In conclusion, this study demonstrates that, in the NHANES (2003–2014) cohort, to reduce all-cause and cancer mortality risks, the optimal dietary fiber intake time is in the evening.     

Food Sources of Fiber and Micronutrients of Concern in Infants and Children in the United Arab Emirates: Findings from the Feeding Infants and Toddlers Study (FITS) and the Kids Nutrition and Health Survey (KNHS) 2020

We estimated the usual intakes of fiber, iron, zinc, calcium, folate, vitamin D, and vitamin A and the top foods that contribute to them among children in the UAE. Dietary intake was assessed using 24 h recalls among 5 age groups of infants and children. Foods were clustered into 54 food groups and ranked by their percentage contribution to the nutrients of interest in this study. The percentage achieving the adequate intake (AI) of fiber was negligible among all children. The top source of fiber was vegetables among children under 4 years, and white breads among those over 4 years. Only 45% of infants achieved iron adequacy, but iron standards were met by most children beyond the age of 1. The main contributors to iron intake were infant/young child formula and baby cereal in children under 4 years, while children over 4 years obtained it primarily from grains (fortified) and meat/fish. Vitamin D was inadequate across all age groups, with the percentage achieving adequacy ranging from 0 to 19% among pre-adolescents and toddlers, respectively. The top sources of vitamin D were fortified milks. Overall, nutrient inadequacies in fiber, calcium, and vitamin D highlight the need for greater intakes of whole grains and fortified dairy products in the UAE.