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1.
Effectiveness of using visual approaches in health education and its influential factors were still in debate. This study aimed to asess the effects of visualized nutrition education on dietary knowledge and behavioral changes, and factors influencing them. A comprehensive search of PubMed, EMBASE, Scopus, and Cochrane Library was conducted. Eligible studies were trials assessed effects of visualized nutrition education on dietary knowledge or behavior changes, compared with non-visualized or no education group. Fourteen studies (n?=?7,259) were qualitatively analyzed and 7 of them were included in the meta-analysis. We found a higher fiber intake in both short term (1.59?g/1000 kcals, 95% CI 0.90–2.27) and long term (1.36?g/1000 kcals, 95% CI 0.64–2.09). A marginal advantage was shown in short-term fruits and vegetables consumption (F&V consumption) (standardized mean difference [SMD]?=?0.08, 95% CI ?0.00 to 0.16). The education effects were more pronounced when education was delivered in series (SMDF&V consumption?=?0.09, 95% CI 0.00–0.17), avoiding loss-framing (SMDFat intake?=?0.31, 95% CI 0.10–0.51) and video modeling (SMDF&V consumption?=?0.23, 95% CI 0.03–0.43), with short length plus cultural adaptation. Visualized nutrition education was overall promising in improving dietary behaviors. Delivering in series, short in length, with cultural adaptation were features tended to enlarge the benefits of visualized education while loss-framing and video modeling might be avoided.  相似文献   

2.
Background: In spite of promising experimental findings, randomized controlled trials (RCTs) have yielded mixed results on the impact of quercetin supplementation on plasma lipid levels.

Aim: The present study aimed to quantify the effects of quercetin on plasma lipids using a meta-analysis of RCTs.

Methods: A systematic literature search of Medline was conducted for RCTs that investigated the efficacy of quercetin supplementation on plasma lipids comprising total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated for net changes in lipid concentrations using a random-effects model. Meta-regression analysis was conducted to assess the effect of quercetin dose and duration of supplementation as moderators on the calculated effect measures.

Results: Five RCTs totaling 442 subjects (221 in the quercetin and 221 in the control group) fulfilled the eligibility criteria and selected for analyses. Combined estimate of effect size for the impact of quercetin on plasma LDL-C (WMD: 1.43 mg/dL, 95% CI: ?0.92–3.78, p = 0.23), HDL-C (WMD: 0.26 mg/dL, 95% CI: ?0.74–1.25, p = 0.61) and triglycerides (WMD: ?9.42 mg/dL, 95% CI: ?27.80–8.96, p = 0.32) was not statistically significant. However, a borderline significant but clinically non-relevant increase in total cholesterol was observed (WMD: 3.13 mg/dL, 95% CI: ?0.01–6.27, p = 0.05). When the analysis was confined to the subgroups of studies with quercetin doses ≥500 mg/day and follow-up of ≥ 4 weeks, a significant increase in total cholesterol (WMD: 3.57 mg/dL, 95% CI: 0.21–6.92, p = 0.04) and a decline in triglycerides (WMD: ?24.54 mg/dL, 95% CI: ?33.09 to ?15.99, p < 0.00001) was observed, but LDL-C and HDL-C concentrations remained unchanged (p > 0.05). Changes in plasma triglycerides, but not other indices of lipid profile, were significantly associated with quercetin dose (slope: ?0.057; 95% CI: ?0.103 to ?0.010; p = 0.02) and duration of supplementation (slope: ?5.314; 95% CI: ?9.482 to ?1.147; p = 0.01).

Conclusion: Available evidence from RCTs does not suggest any clinically relevant effect of quercetin supplementation on plasma lipids, apart from a significant reduction of triglycerides at doses above 50 mg/day.  相似文献   

3.
This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of ginger intake on weight loss, glycemic control and lipid profiles among overweight and obese subjects. We searched the following databases through November 2017: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The relevant data were extracted and assessed for quality of the studies according to the Cochrane risk of bias tool. Data were pooled using the inverse variance method and expressed as Standardized Mean Difference (SMD) with 95% Confidence Intervals (95% CI). Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I2). Overall, 14 studies were included in the meta-analyses. Fourteen RCTs with 473 subjects were included in our meta-analysis. The results indicated that the supplementation with ginger significantly decreased body weight (BW) (SMD ?0.66; 95% CI, ?1.31, ?0.01; P = 0.04), waist-to-hip ratio (WHR) (SMD ?0.49; 95% CI, ?0.82, ?0.17; P = 0.003), hip ratio (HR) (SMD ?0.42; 95% CI, ?0.77, ?0.08; P = 0.01), fasting glucose (SMD ?0.68; 95% CI, ?1.23, ?0.05; P = 0.03) and insulin resistance index (HOMA-IR) (SMD ?1.67; 95% CI, ?2.86, ?0.48; P = 0.006), and significantly increased HDL-cholesterol levels (SMD 0.40; 95% CI, 0.10, 0.70; P = 0.009). We found no detrimental effect of ginger on body mass index (BMI) (SMD ?0.65; 95% CI, ?1.36, 0.06; P = 0.074), insulin (SMD ?0.54; 95% CI, ?1.43, 0.35; P = 0.23), triglycerides (SMD ?0.27; 95% CI, ?0.71, 0.18; P = 0.24), total- (SMD ?0.20; 95% CI, ?0.58, 0.18; P = 0.30) and LDL-cholesterol (SMD ?0.13; 95% CI, ?0.51, 0.24; P = 0.48). Overall, the current meta-analysis demonstrated that ginger intake reduced BW, WHR, HR, fasting glucose and HOMA-IR, and increased HDL-cholesterol, but did not affect insulin, BMI, triglycerides, total- and LDL-cholesterol levels.  相似文献   

4.
An experiment is described in which the daily metabolisable energy (ME) intake of light and medium weight hybrid pullets fed a concentrated diet (ME = 3720 kcal/kg) was restricted directly on an individual hen basis (95, 85 and 75 g/day) and also by dilution of the diet using wood dust as the diluent (13.6, 22.7 and 31.8% wood dust). The concentrated diet and a high-energy diet (ME = 2750 kcal/kg) were also fed ad libitum. Total egg weight and percentage egg production were not significantly different for hens fed the concentrated diet ad libitum, at the first two levels of restriction or at the lowest level of dilution. Both direct restriction and restriction by dilution of the diet resulted in greatly reduced liveweight gains. Direct restriction of the ME intake resulted in a marked improvement of ME conversion to egg product (Mcal/kg eggs). Dilution of the diet had a detrimental effect on the ME conversion. Calculations, based on calorimetric data, of the ME requirement for maintenance and production (eggs plus bodyweight gain) showed that direct restriction resulted in observed ME intakes which, although higher, were closer to the calculated ME requirements than did ad libitum feeding. Restriction of ME intake by dilution of the diet resulted in the actual ME intakes being much greater than the calculated requirements, the difference being 70 and 50% of the calculated ME requirements at the 31.8% level of dilution for the light and medium hybrids, respectively. The possible reasons for the difference between the calculated ME requirements based on calorimetric data and the observed ME intakes obtained in the practical laying trial are discussed.  相似文献   

5.
Data about harms or benefits associated with the consumption of aspartame, a nonnutritive sweetener worldwide consumed, are still controversial. This systematic review and meta-analysis of randomized controlled clinical trials aimed to assess the effect of aspartame consumption on metabolic parameters related to diabetes and obesity. The search was performed on Cochrane, LILACS, PubMed, SCOPUS, Web of Science databases, and on a gray literature using Open Grey, Google Scholar, and ProQuest Dissertations &; Theses Global. Searches across all databases were conducted from the earliest available date up to April 13, 2016, without date and language restrictions. Pooled mean differences were calculated using a random or fixed-effects model for heterogeneous and homogenous studies, respectively. Twenty-nine articles were included in qualitative synthesis and twelve, presenting numeric results, were used in meta-analysis. Fasting blood glucose (mmol/L), insulin levels (μU/mL), total cholesterol (mmol/L), triglycerides concentrations (mmol/L), high-density lipoprotein cholesterol (mmol/L), body weight (kg), and energy intake (MJ) were considered as the main outcomes in subjects that consumed aspartame, and results were presented as mean difference; % confidence interval, range. Aspartame consumption was not associated with alterations on blood glucose levels compared to control (?0.03 mmol/L; 95% CI, ?0.21 to 0.14) or to sucrose (0.31 mmol/L; 95% CI, ?0.05 to 0.67) and on insulin levels compared to control (0.13 μU/mL; 95% CI, ?0.69 to 0.95) or to sucrose (2.54 μU/mL; 95% CI, ?6.29 to 11.37). Total cholesterol was not affected by aspartame consumption compared to control (?0.02 mmol/L; 95% CI, ?0.31 to 0.27) or to sucrose (?0.24 mmol/L; 95% CI, ?0.89 to 0.42). Triglycerides concentrations were not affected by aspartame consumption compared to control (0.00 mmol/L; 95% CI, ?0.04 to 0.05) or to sucrose (0.00 mmol/L; 95% CI, ?0.09 to 0.09). High-density lipoprotein cholesterol serum levels were higher on aspartame compared to control (?0.03 mmol/L; 95% CI, ?0.06 to ?0.01) and lower on aspartame compared to sucrose (0.05 mmol/L; 95% CI, 0.02 to 0.09). Body weight did not change after aspartame consumption compared to control (5.00 kg; 95% CI, ?1.56 to 11.56) or to sucrose (3.78 kg; 95% CI, ?2.18 to 9.74). Energy intake was not altered by aspartame consumption compared to control (?0.49 MJ; 95% CI, ?1.21 to 0.22) or to sucrose (?0.17 MJ; 95% CI, ?2.03 to 1.69). Data concerning effects of aspartame on main metabolic variables associated to diabetes and obesity do not support a beneficial related to its consumption.  相似文献   

6.
This study examined the association between the nutrient contribution of beef, in its lowest and highest fat forms, and diet quality and food patterns in individuals 4+ years of age. Beef consumers were categorized into three groups (lowest lean/highest fat [LLHF]; middle lean/middle fat content; and highest lean/lowest fat [HLLF]) based on the lean and fat content of beef consumed. Compared to non-beef consumers, HLLF consumers had higher intakes of vitamins B6 and B12, iron, zinc, and potassium. Non-beef consumers had higher intakes of thiamin, folate, calcium, and magnesium than HLLF beef consumers. The HLLF group had significantly higher intakes of vitamins A, C, B6, and B12; niacin; phosphorus; magnesium; iron; zinc; and potassium, protein and lower intakes of total energy; total fat; SFA; MUFA; total carbohydrates. There was no difference in diet quality between HLLF beef consumers and non-beef consumers. Moderate consumption of lean beef contributes to intakes of selected nutrients and diet quality was similar to non-beef consumers.  相似文献   

7.
This study used simple rapid-assessment techniques to test the feasibility of increasing the consumption of complementary foods by infants by asking mothers to increase meal quantity or frequency or by altering the viscosity/energy density of the food. The feasibility of using micronutrient supplements either added directly to food or administered as liquid drops was also examined. The study was conducted in rural Bangladesh and involved four separate short-term behavioral change trials. Depending on the trial, fieldworkers recruited 30 to 45 infants 6 to 12 months of age. Following recommendations to increase the amount of food provided to infants, the mean intakes from single meals increased from 40 +/- 23 g on day 1 to 64 +/- 30 g on day 7 (p < 0.05). In a second trial, the mean meal frequency increased from 2.2 +/- 1.3 on day 1 to 4.1 +/- 1.3 on day 7 (p < 0.05). Provision of high-energy-density diets, prepared by decreasing viscosity with alpha-amylase or by hand-mashing rice and dhal into a paste before feeding, increased single-meal energy consumption from 54 +/- 35 kcal to 79 +/- 52 kcal or 75 +/- 37 kcal (p < 0.05), respectively. Both types of micronutrient supplements were well accepted and used according to recommendations. In conclusion, it was possible to change short-term child-feeding behaviors to promote increased food intake, mealfrequency, energy density, and micronutrient consumption. Because each of these interventions lasted for only about 1 week, however, the long-term sustainability of these changes is not known. Moreover, the effect of increased feeding of complementary foods on intakes of breastmilk and total daily consumption of energy and nutrients requires further study.  相似文献   

8.
The objective was to determine whether increased energy and protein intake between 2 and 14 wk of age would increase growth rates of heifer calves without fattening. At 2 wk of age, Holstein heifer calves were assigned to 1 of 4 treatments in a 2 x 2 factorial arrangement with 2 levels of protein and energy intake (moderate [M]; high [H]) in period 1 (2 to 8 wk of age) by 2 levels of protein and energy intake (low [L]; high [H]) in period 2 (8 to 14 wk of age) to produce similar initial BW for all 4 treatments. Treatments were ML, MH, HL, and HH, indicating moderate or high energy and protein intake during the first period and low or high intake during the second period. The M diet consisted of a standard milk replacer (21.3% CP, 21.3% fat) fed at 1.1% of BW on a DM basis and a 16.5% CP grain mix fed at restricted intake to promote 400 g of average daily gain (ADG), whereas the L diet consisted only of the grain mix. The H diet consisted of a high-protein milk replacer (30.3% CP, 15.9% fat) fed at 2% of BW on a DM basis and a 21.3% CP grain mix available ad libitum. Calves were weaned gradually from milk replacer by 7 wk and slaughtered at 8 (n = 11) or 14 wk of age (n = 41). In periods 1 and 2, ADG and the gain:feed ratio were greater for calves fed the H diet. Calves fed the H diet were taller after both periods 1 and 2. No difference was observed in carcass composition at 8 wk, but at 14 wk calves fed MH and HH had less water and more fat than calves fed ML and HL. Plasma IGF-I concentrations were greatest for calves fed the H diet during either period. Plasma leptin concentrations were increased in calves fed the H diet during period 1 from 4 to 6 wk of age. Increasing energy and protein intake from 2 to 8 wk and 8 to 14 wk of age increased BW, withers height, and gain:feed ratio. Calves fed the H diet from 8 to 14 wk of age had more body fat than calves fed the L diet. Increased energy and protein intake can increase the rate of body growth of heifer calves and potentially reduce rearing costs.  相似文献   

9.
Background: The influence of dietary fat upon breast cancer mortality remains largely understudied despite extensive investigation into its influence upon breast cancer risk. Objective: To conduct meta-analyses of studies to clarify the association between dietary fat and breast cancer mortality. Design: MEDLINE and EMBASE were searched for relevant articles published up to March 2012. Risk of all-cause or breast-cancer-specific death was evaluated by combining multivariable adjusted estimates comparing highest versus lowest categories of intake; and per 20 g increase in intake of total and/or saturated fat (g/day) using random-effects meta-analyses. Results: Fifteen prospective cohort studies investigating total fat and/or saturated fat intake (g/day) and breast cancer mortality were included. There was no difference in risk of breast-cancer-specific death (n = 6; HR = 1.14; 95% CI: 0.86, 1.52; p = 0.34) or all-cause death (n = 4; HR = 1.73; 95% CI: 0.82, 3.66; p = 0.15) for women in the highest versus lowest category of total fat intake. Breast-cancer-specific death (n = 4; HR = 1.51; 95% CI: 1.09, 2.09; p < 0.01) was higher for women in the highest versus lowest category of saturated fat intake. Conclusions: These meta-analyses have shown that saturated fat intake negatively impacts upon breast cancer survival.  相似文献   

10.
PURPOSE: In this study, the Dietary Reference Intake standards were used to evaluate the prevalence of inadequate intakes of micronutrients in obese and non-obese youth. METHODS: Dietary intake was analyzed with a dietary history taken by a registered dietitian. The obese group (n=156) had a body mass index (BMI) above the 95th percentile for age and sex. The non-obese group (n=90) was between the tenth and 85th BMI percentiles. RESULTS: In the obese subjects, the prevalence of inadequate intakes was 81% for vitamin E and 27% for magnesium; the proportions with intakes below the Adequate Intakes (AIs) for calcium and vitamin D were 55% and 46%, respectively. The obese children consumed 124% of estimated need for energy, 32% of which came from fat. The non-obese had a similar prevalence of inadequate intakes (vitamin E, 93%; magnesium, 29%; calcium, 51%; vitamin D, 44%). They consumed 107% of estimated need for energy, and 31% of energy came from fat. For both groups, all other nutrient intakes were adequate. CONCLUSIONS: Even though children may consume an excess of energy, they may not be meeting all of their micronutrient needs.  相似文献   

11.
目的评估芦荟全叶及其粗提取物质对糖尿病大鼠血糖的影响。方法通过检索1985年1月到2014年3月的MEDLINE、FMJS(EMCC)、OVID、中国期刊全文数据库(CNKI)、维普中文科技期刊数据库(VIP)和万方数据库等文献数据库,选择以血糖为分析指标的糖尿病大鼠随机对照实验进行系统评价。由两名评价者按照排除纳入标准独立阅读并提取相关文献。结果经过筛选,最终纳入8篇文献进行评价。与对照组相比,芦荟对血糖的总体效应为[SMD-6.20,95%CI(-9.72,-2.67)],采用随机效应模型分析结果有统计学意义(P0.00001),提示芦荟对大鼠具有一定的降血糖作用。由于异质性较大(I2=94%),经亚组分析后,长期摄取芦荟的糖尿病大鼠血糖有一定改善(P=0.003),而短期摄取芦荟的糖尿病大鼠血糖改善不明显(P=0.72)。结论芦荟具有一定程度的降低糖尿病大鼠血糖的作用。  相似文献   

12.
Aim of study was to assess trends in lipid profile and nutrition of adolescent population in Novosibirsk during the social and economic reforms in Russia (1989-1999). Three cross-sectional studies of school aged 14-17 in 1989 (657), in 1994 (620) and in 1999 (626) were carried out. Total sample was 1903 (914 males and 989 females). Blood lipids, such as total cholesterol (TC0, high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG), were measured. Diet was estimated with the method of 24-hour dietary recall. During 10-year period mean serum TC decreased from 175 to 158 mg/dl in males and from 191 to 175 mg/dl in females (p < 0.001 for both genders). Females had significantly higher mean NC than did males at all surveys (p < 0.001)/Between 1989 and 1994 mean HDL-C levels decreased in boys both (p < 0.001), but in 1999 these levels were similar to 1989. During 1989-1994, TG levels significantly decreased, but between 1994 and 1999 mean TG levels increased in 1.5 times in both gender groups. Prevalence of high TC (> = 2000 mg/dl) significantly decreased from 17% to 6% in males and from 28% to 14% in females. Frequencies of low HDL-C (> = 40 mg/dl) also decreased in boys (from 28 to 8%) and girls (from 13 to 3%). Trends in diet showed similar changes and characterized by significant decreasing of total energy intakes (from 3021 to 2342 kcal in boys and from 2300 to 1644 kcal in girls) and of basic nutrient intakes (proteins? Fats? Carbohydrates). Negative trends in blood lipid profile and diet in adolescents during the unstable period of socioeconomic reforms in Russia indicate on serious changes in metabolic processes and need in large state economic programs to improve the situation.  相似文献   

13.
目的:膳食营养可影响结核病发生发展和预后,本文调查结核病患者膳食营养素摄入状况及存在的问题,为指导患者合理营养膳食提供科学依据。方法:选取某农村地区结核病患者1955人为病例组,正常人群1955人为对照组,两组人群进行了良好的匹配,平均年龄、性别比例相近,生活习惯及家庭条件相似。应用食物频率表收集调查对象消费的食物种类,24h膳食回顾法收集调查对象膳食营养素摄入情况。结果:膳食调查结果显示,结核病患者每日能量和蛋白质摄入量分别为I712kCal和65.73g,仅达到推荐摄入量的71.55%和87.64%,且明显低于健康对照组人群的1855kCal(P〈0.001)和70.36g(P〈0.001);一些维生素及矿物质每日摄入量也明显不足,其中结核病患者视黄醇和钙的摄入量仅分别为320.59μg视黄醇当量和295.69mg,为推荐摄入量40.08%和56.96%,也明显低于对照组平均水平(P均小于0.0001)。膳食多样化评分(DDS)结果显示,两组人群DDS评分均为6.51,日常饮食能保持7种及以上食物组成的人数比例病例组和对照组分别可达到52.94%和49.16%;而有5.78%结核病患者得分仅为5分,即日常饮食的食物种类只有5类,明显高于对照组人群的2.66%;2.10%结核病患者得分仅为2分,也明显高于对照组的1.18%,表明结核病患者膳食单调或种类单一。食物消费种类结果显示,结核病患者食物以谷类为主,可达gO%以上,鱼虾类和奶类消费率低,仅为25.58%和57.08%;同样的问题也存在于对照组人群。结论:农村结核病患者及健康人群能量、视黄醇、钙等营养素摄入量偏低,结核病患者不足更为突出,与膳食不平衡有关;建议积极改善营养及膳食结构,有效防治结核病。  相似文献   

14.
Wholegrains are a rich source of phytochemicals, dietary fibre, complex carbohydrate, proteins, minerals, lipids and vitamins that may have the tendency to increase heath beyond the simple provision of nutrition and energy. They are highly nutritive due to their balanced amino acid profile and other macro- and micronutrient composition. It is considered well-balanced diet having functional characteristics that have shown to possess medicinal benefits. The inverse relation between consumption of wholegrains and the reduced risk of chronic diseases and metabolic syndromes are reported in several studies. The consumption of wholegrains is on the rise due to the growing health-conscious populace and health-promoting components support the dietary consumption of wholegrains and their products. Accordingly, the conclusive evaluation of wholegrains and the human intervention studies conducted for the whole grain intake, and the inference that the wholegrains, functional properties and the health outcomes associated with wholegrains are discussed.  相似文献   

15.
A meta-analysis of prospective cohort studies was conducted to examine the relation between fruit and vegetables (FV) consumption and the risk of cardiovascular disease (CVD). We searched PubMed and EMBASE up to June 2014 for relevant studies. Pooled relative risks (RRs) were calculated and dose–response relationship was assessed. Thirty-eight studies, consisting of 47 independent cohorts, were eligible in this meta-analysis. There were 1,498,909 participants (44,013 CVD events) with a median follow-up of 10.5 years. The pooled RR (95% confidence interval) of CVD for the highest versus lowest category was 0.83 (0.79–0.86) for FV consumption, 0.84 (0.79–0.88) for fruit consumption, and 0.87 (0.83–0.91) for vegetable consumption, respectively. Dose–response analysis showed that those eating 800 g per day of FV consumption had the lowest risk of CVD. Our results indicate that increased FV intake is inversely associated with the risk of CVD. This meta-analysis provides strong support for the current recommendations to consume a high amount of FV to reduce CVD risk.  相似文献   

16.
Aluminium is found naturally in foods and beverages, but levels increase notably during processing, packaging, storage, and cooking, as a consequence of its presence in food additives and the wide use of aluminium utensils and vessels. Dietary intake of Al was estimated in 2 population groups in southern Spain (families and university students) in a duplicate diet sampling study. Diets were sampled for 7 consecutive days, and Al was determined in acid‐mineralized samples with electrothermal atomization‐atomic absorption spectrometry (ETA‐AAS). Mean values for Al intake were 2.93 and 1.01 mg/d in families and students, respectively, ranging from 0.12 to 10.00 mg/d. Assuming an average adult weight of 60 kg, the mean dietary exposures to aluminium were 0.34 and 0.12 mg/kg body weight/week in these groups, which amounted to 17% and 6% of the 2 mg/kg body weight estimated as the tolerable weekly intake by the Joint FAO/WHO Expert Committee on Food Additives. Bioaccessibility of dietary Al tested with in vitro studies ranged from 0.30 to 17.26% (absorbable fraction). The highest aluminium intakes were observed in subjects consuming diets with a low adherence to the Mediterranean diet, which were associated to high consumption of processed and canned food. On the contrary, subjects consuming diets with a high adherence to the Mediterranean diet patterns showed the lowest Al intakes. The present findings are useful for giving both a reliable estimate of total aluminium dietary intake and tolerable intake levels according to usual dietary habits.  相似文献   

17.
The effect of drastic undernutrition was studied in Bos indicus cows. Four nonlactating cows (body weight = 208 kg) fitted with ruminal cannulas were used in a crossover design. They received, in two 1-mo periods, a diet of 80% rice straw and 20% cotton-seed meal fed either at energy maintenance [3.91 kg of dry matter (DM)/d] or at one-third of this intake (1.30 kg of DM/d). The variation in digestibility was studied in relation to particle retention time and microbial events. Organic matter digestibility decreased with underfeeding (64.5 and 53.7%, respectively, at high and low intakes) without modification of mean ruminal or total tract retention times. This lower digestibility can be related to a decrease in protozoal population in the rumen; however, other characteristics of microbial activity did not vary, such as in situ DM degradability (41.9 and 43.3%, respectively, at high and low intakes) and ruminal soluble Ca concentration, a factor involved in the attachment of microorganisms to feed particles. Mean size of ruminal particles was not modified, although more time spent chewing was observed at the low intake (165 and 221 min/kg of DM intake, respectively, at high and low intakes). This experiment confirms that, at intakes below maintenance, digestibility can decrease when feed intake is restricted, contrary to the general view described in the literature.  相似文献   

18.
An agricultural project in Highland Ecuador provided a model context to better understand the nutrition of rural women. The adequacy of women's nutrition and the strength of associations with age and socioeconomic status were studied in 104 rural households over four rounds (two seasons) during the 1995-1996 agricultural year using a cross-sectional with repeated-measures design. Women were at high risk for micronutrient deficiencies (calcium, iron, riboflavin, and vitamin B12) due to low intakes of animal products. Two distinct constructs representing socioeconomic status were identified: modern lifestyle and farming wealth. In multivariate models, farming wealth was associated with quality of women's diet (animal protein adjusted for energy, p = 0.01). Diet quality, in turn, was positively associated with anthropometric status (p = 0.02). Women over the age of 50 weighed approximately 3.7 kg less than younger women and consumed less energy (300 kcal) and micronutrients (p < 0.05). Age was positively associated with respiratory morbidity (p = 0.01). These findings, while directly relevant to a specific context, suggest the need for cross-cultural studies to identify the extent of, and factors contributing to, the risk of nutritional inadequacy in postreproductive women in developing countries.  相似文献   

19.
Pasteurization of milk ensures safety for human consumption by reducing the number of viable pathogenic bacteria. Although the public health benefits of pasteurization are well established, pro-raw milk advocate organizations continue to promote raw milk as "nature's perfect food." Advocacy groups' claims include statements that pasteurization destroys important vitamins and that raw milk consumption can prevent and treat allergies, cancer, and lactose intolerance. A systematic review and meta-analysis was completed to summarize available evidence for these selected claims. Forty studies assessing the effects of pasteurization on vitamin levels were found. Qualitatively, vitamins B12 and E decreased following pasteurization, and vitamin A increased. Random effects meta-analysis revealed no significant effect of pasteurization on vitamin B6 concentrations (standardized mean difference [SMD], -2.66; 95% confidence interval [CI], -5.40, 0.8; P = 0.06) but a decrease in concentrations of vitamins B1 (SMD, -1.77; 95% CI, -2.57, -0.96; P < 0.001), B2 (SMD, -0.41; 95% CI, -0.81, -0.01; P < 0.05), C (SMD, -2.13; 95% CI, -3.52, -0.74; P < 0.01), and folate (SMD, -11.99; 95% CI, -20.95, -3.03; P < 0.01). The effect of pasteurization on milk's nutritive value was minimal because many of these vitamins are naturally found in relatively low levels. However, milk is an important dietary source of vitamin B2, and the impact of heat treatment should be further considered. Raw milk consumption may have a protective association with allergy development (six studies), although this relationship may be potentially confounded by other farming-related factors. Raw milk consumption was not associated with cancer (two studies) or lactose intolerance (one study). Overall, these findings should be interpreted with caution given the poor quality of reported methodology in many of the included studies.  相似文献   

20.
Scope Fish liver, fish liver oil, oily fish and seagull eggs have been major sources of vitamin D for the coastal population of Norway. They also provide dioxin and polychlorinated dioxin‐like compounds (dl‐compounds), which may interfere with vitamin D homeostasis. We investigated whether serum 25‐hydroxyvitamin D (25(OH)D) might be compromised by concomitant intake of dl‐compounds. Methods and results We studied 182 adults participating in the Norwegian Fish and Game Study. Participants who consumed fish liver and/or seagull eggs had higher dl‐compound intake and blood concentrations than non‐consumers (p < 0.001). Vitamin D intake was higher (p < 0.001), whereas serum 25(OH)D was lower (p = 0.029) in consumers than in non‐consumers. Among non‐consumers, vitamin D intake was associated with serum 25(OH)D (β=1.06; 95% CI: 0.48, 1.63). This association was weaker among consumers (β = 0.52; 95% CI: ?0.05, 1.08), but strengthened when adjusted for retinol intake (β = 0.66; 95% CI: 0.12, 1.21). The association between vitamin D intake and serum 25(OH)D did not seem to be compromised by intake of dl‐compounds. Conclusion To secure adequate vitamin D status while keeping the intake of dioxins and dl‐polychlorinated biphenyls low, a healthy diet should include both supplemental vitamin D and oily fish. Despite high nutrient content, dietary fish liver and seagull eggs should be restricted, due to dl‐compounds and possible vitamin A‐D antagonism.  相似文献   

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