能量补充类运动食品的研究现状

运动食品能够满足运动员在运动过程中的特殊营养需求,能够提高运动员的体能和体质。能量补充类运动食品是运动食品中的一类,其主要成分是糖类物质,能够快速补充运动员在运动训练中消耗的大量能量,缓解运动疲劳。不同运动类型的运动员需补充的运动食品有所不同,了解运动食品的分类以及运动食品的功能性成分,对帮助运动员选择适宜的运动产品十分重要。本文介绍了速度型运动类型、耐力型运动类型、力量型运动类型以及技巧型运动类型与运动员的营养需求的关系,运动食品的分类,糖类物质对运动的影响,肌糖原的合成与消耗,肌糖原与运动的关系,并针对能量补充剂的功能因子葡萄糖、肌酸、L-肉碱进行了介绍,为能量补充类运动食品的研发提供理论参考。     

Effects of a food supplementation program on the nutritional status of pregnant women in Bangladesh

BACKGROUND: The Government of Bangladesh implemented a comprehensive nutrition intervention in 1997 to reduce the rates of malnutrition among women and children. The pilot program, the Bangladesh Integrated Nutrition Program (BINP), adopted a multisectoral approach targeting women and children through food supplementation, home gardening, and health and nutrition education. OBJECTIVE: This paper estimates the effectiveness of BINP's food supplementation and nutrition education on the nutritional status of pregnant women. Methods. Three effectiveness measures were considered: target efficiency, improvements in the nutritional status of beneficiaries, and the persistence of nutritional effects. To isolate the effects of the intervention, the nutritional status of participants and nonparticipants was compared after controlling for various demographic and socioeconomic characteristics. Data were collected in 2000 from a random sample of 3262 households in a BINP intervention area. RESULTS: Thirty-nine percent of pregnant women were correctly targeted by the program's food supplementation activities. The nutrition program reduced the prevalence of thinness among participant pregnant women by about 3 percentage points per month of enrollment. The prevalence of thinness among program graduates was 62%, which was much higher than that of the matched (nonparticipant) group (35%). This finding is perplexing but it may simply imply that those who enrolled at the initial phase of the project were severely underweight and they fell back to their original status within a short period of time. CONCLUSIONS: The nutrition program was intended to improve the nutritional status of women in the longer run through the provision of nutrition education during the food supplementation phase. The prevalence of thinness or severe underweight in women who exited the program after completion of the enrollment period was found to be much higher than in women of similar age and socioeconomic status in the community. This apparent lack of persistence of program benefits requires careful re-evaluation of alternative mechanisms for improving the long-term nutritional status of women.     

运动营养食品的研究现状与发展趋势

在"体育强国"、"全民健身"的时代背景下,运动营养食品产业蓬勃发展,随着大众健康意识的普遍提高,运动营养食品将迎来新的高潮。本文从运动营养食品的定义出发,总结大众对运动以及运动营养食品的认知程度,分析运动营养食品的研究现状,指出我国运动营养食品在产品研发、食品安全以及适应国情方面存在的不足并给出相应的建议,并且就其发展趋势进行了一定的探讨,以期为运动营养食品行业的发展提供一定的参考。     

Effect of iodine status and other nutritional factors on psychomotor and cognitive performance of Filipino schoolchildren

BACKGROUND: Until 1998, iodine deficiency was a public health problem in the Philippines. A law entitled "An Act Promoting Salt Iodization Nationwide" (ASIN) has been passed and implemented by the government to eliminate iodine deficiency. The contribution of salt iodization, as well as dietary, health, and environmental factors, to improving the intellectual performance of Filipino schoolchildren remains to be determined. OBJECTIVE: The objectives of the study were to determine the relationship between iodine status and levels of psychomotor and cognitive performance in first-grade children aged 6 to 10 years, and to examine the extent to which dietary, biochemical, health, and environmental factors contribute to children's mental performance. METHODS: Two hundred ninety children in six classroom sections from a public school in Manila were examined by measurement of urinary iodine excretion (UIE) and thyroid palpation. The median UIE level for each section was determined. Sixty-five children classified as iodine deficient (UIE < 90 microg/L with grade 1 goiter, n = 34) and non-iodine deficient (UIE > 100 microg/L without goiter, n = 31) were given psychomotor and cognitive function tests (Bender-Gestalt and Raven's Colored Progressive Matrices). Scores from the two tests were used to determine each child's general ability percentile rank. Other variables examined were dietary intake (% RDA of nutrients ingested based on two nonconsecutive 24-hour recalls); deficiencies in iron, vitamin A, and selenium; parasitic infection; coliform contamination of drinking water; household use of iodized salt; illness in the past 2 weeks; and wasting and stunting. RESULTS: Children whose general ability scores were at or above the 50th percentile had higher UIE levels, but the relationship was not significant. Children from sections with higher median UIE levels had higher percentile ranks for general ability (p = .002). Backward logistic regression showed that the variance in deficient and adequate mental performance was explained by dietary intakes that met > or = 80% of the RDA for energy, protein, thiamin, and riboflavin; the use of iodized salt; child's iodine status; and stunting (R2 = .520, p = .0016). Higher class median UIE was associated with better psychomotor and cognitive performance in children who were tested. Factors that contributed to better performance include higher intakes of energy, protein, thiamin, and riboflavin; household use of iodized salt; normal iodine status; and absence of stunting or chronic malnutrition. CONCLUSIONS: Salt iodization, accompanied by adequate intakes of energy, protein, and foods rich in thiamin and riboflavin, can contribute to improved mental performance in Filipino schoolchildren. Longer-term factors that can contribute to improved performance are achievement of normal iodine status and elimination of protein-energy malnutrition.     

Regional study of nutritional status of urban primary schoolchildren. 1. Manila, Philippines

This multicity study sought to provide baseline information on the nutritional status of urban schoolchildren in order to examine the emerging problem of overweight and obesity in this age group. The study included 1,208 children 8 to 10 years old who were randomly selected from all public and private schools in Manila for weight and height measurements. Nutritional status was assessed by weight-for-age and height-for-age Z scores and BMI percentile cutoff points. On the average, private schoolchildren were taller and heavier and had higher body mass index (BMI) values than public schoolchildren, resulting in a much lower prevalence of undernutrition and a much higher prevalence of overnutrition. These results have important programmatic implications. However, using the World Health Organization (WHO)--recommended cutoff points to define under- and overnutrition gave contrasting results when weight-for-height and BMI were used. There appears to be a need to validate the anthropometric reference standards and cutoff points in children and adolescents to better define nutritional status and ascertain the influence of ethnicity.     

Iron status in a population of Spanish schoolchildren

Iron status was assessed in a population of 196 schoolchildren and adolescents divided into three age groups: 6–7 years (n = 60), 10–12 years (n = 63) and 13–15 years (n = 73). All subjects were from the Vélez-Málaga area (province of Málaga) in southern Spain. Nutrient intakes and biochemical parameters related with iron status (number of red cells, hematocrit, hemoglobin, serum iron concentration, total iron-binding capacity and transferrin saturation) were measured. The results showed a lack of correlation between the nutrient intake and biochemical findings. Food intake calculations suggested that adolescent girls between 13 and 15 years of age were at greatest risk for iron deficiency (intakes covered only 71.6% and 84% of the iron and folic acid RDAs, respectively), followed by 10–12 year old girls and 6–7 year old boys. However, groups in which iron deficiency was most frequent according to the biochemical data were 6–7 year old boys (10%), followed by 13–15 year old adolescent boys (2.9%).     

Regional study of nutritional status of urban primary schoolchildren. 3. Kuala Lumpur, Malaysia

A total of 5,995 (7.8% of all 7- to 10-year-old primary schoolchildren in Kuala Lumpur), randomly selected from 166 schools (97.6% of all schools), were measured for their weight and height. The analyses of all weight and height data, including the cutoffs used for defining stunting, underweight, and wasting and for thinness and overweight, were carried out as recommended by the World Health Organization (WHO). The prevalances of stunting (height-for-age Z score < -2 SD), underweight (weight-for-age Z score < -2 SD) and wasting (weight-for-height Z score < -2 SD) among all the children studies were 6.7%, 7.1%, and 4.5%, respectively. Undernutrition among boys was more serious than among girls according to all three indicators. Because it was not possible to analyze the weight-for-height data for most of the children above 8.5 years of age, body mass index (BMI)-for-age was used to determine the prevalences of thinness and overweight for all the children. Based on the reference data, the prevalence of overweight (at or above the 95th percentile) was 9.7% and 7.1% for boys and girls, respectively, and 8.4% overall.     

血红素铁改善缺铁性贫血效果观察

目的 了解血红素铁对缺铁性贫血的影响.方法 将符合贫血诊断的女性108人随机分为血红素铁组和对照组,并分别给予血红素铁和安慰剂,连续服用45 d,服用开始前和服用结束时对受试者进行膳食营养调查、体格检查和血液生化指标的检测并进行统计学分析.结果 血红素铁组血红蛋白的含量由试验前的(106.43±10.48) g/L上升到(117.34±10.25)g/L,平均升高了10.91 g/L(服用前后配对t检验,P＜0.05,服用后与对照组t检验,P＜0.05);红细胞游离原卟啉的含量由(942.15±96.34)μg/L下降为(820.53±109.95)μg/L(服用前后配对t检验,P＜0.05,服用后与对照组t检验,P＜0.05);试验组血清铁蛋白的含量由试验前的(25.19±6.71) ng/ml上升到(25.40±6.69) ng/ml,(服用前后配对t检验,P＞0.05).结论 血红素铁对缺铁性贫血具有一定的改善作用.并对受试者健康无不良影响.     

Regional study of nutritional status of urban primary schoolchildren. 2. West Jakarta and Bogor, Indonesia

The study provides information on the nutritional status of 8- to 10-year-old primary schoolchildren in urban areas of Jakarta and Bogor, Indonesia, based on anthropometric indicators. It compares the use of the anthropometric indicators weight-for-age Z score, height-for-age Z score, weight-for-height Z score, and body mass index (BMI) to assess thinness (underweight and wasted) and overweight in children. A total of 1,367 children were examined. The nutritional status of the 8- to 10-year urban schoolchildren was better than that of urban children under 5 years old. The prevalence of underweight among urban schoolchildren ranged from 7.4% (girls) to 12.95% (boys), while underweight among urban children under 5 years old in 1998 was 29.7%. Meanwhile, the prevalence of overweight (BMI > 85th percentile) ranged from 15.3% (girls) to 17.8% (boys). There were more overweight children in the private schools than in the public schools. On average, private schoolchildren, of all ages and both sexes, were heavier and taller than public schoolchildren. The BMI indicator for "thinness" and "wasting", using the NHANES reference, indicates a false positive result. For detecting overweight in children aged 8 to 10 years, BMI is comparable to the other indices, weight-for-age, height-for-age, and weight-for-height.     

Influence of nutritional knowledge on the use and interpretation of Spanish nutritional food labels

The present study analyzed the nutritional knowledge of Spanish consumers and its relationship with the correct use of food labels. Consumers were asked about their nutritional knowledge and some functional foods and about their understanding of food labeling and their use of it to select healthy food. A 2-part questionnaire was employed. The 1st part concerned their knowledge of nutritional facts, including their knowledge about macronutrients and perception of certain functional foods, while the 2nd part addressed some questions regarding food labels. The results revealed no statistically significant differences in nutritional knowledge by either age or gender, but a direct relationship with educational level. The association between nutritional knowledge and the perception and understanding of food labeling showed that the nutritional label rarely influenced the food purchases of the group with low nutritional knowledge, who considered that this information was too technical. More than half of the consumers did not consider the calorie or sugar content important for selecting food. In addition, the group with low nutritional knowledge stated that they never or rarely looked at the food labels to check whether it was low-fat food that they were buying. PRACTICAL APPLICATION: Knowing the status of the consumer's nutritional knowledge allows health campaigns to be designed; considering the influence of cultural factors and the perception of food labeling is very useful for promoting better nutritional information.     

Development of a liquid nutritional supplement using a Sesamum indicum L. protein isolate

This work presents some functional properties and the potential use of a new protein isolate from sesame seed flour, Sesaprot^® (SP), as protein source in a liquid nutritional supplement. It was compared to a commercial soybean isolate and results showed that its emulsifying properties are better than those of its soybean counterpart. Lysine content is lower than FAO recommendations for children, but is adequate for adults. Other essential amino acids, however, are present in adequate amounts for any kind of consumer. Osmolality, pH and emulsion stability of an experimental formulation were similar to those of commercial beverages. A consumer sensory test indicated that the product was preferred to one prepared with a soybean isolate and to a commercial brand that was assayed.     

Role of topical and nutritional supplement to modify the oxidative stress

Background: Evidence suggests that signs of skin ageing such as wrinkling, ragging and actinic lentigines, may be connected to cumulative oxidative damage incurred throughout our lifetimes. To counteract this oxidative injury, skin is equipped with a network on enzymatic and non-enzymatic antioxidant systems, such as tocopherols, ascorbate polyphenols. All these compounds administered topically by cosmetics or by oral route by diet supplements, have been shown to exert an antioxidant/protective effect in skin or skin cells. Objective: The object of this study was to evaluate both in vitro and in vivo the activity performed by different topical antioxidants and nutritional supplements. Methods: A randomized double-blind placebo-controlled study was carried out for 8 weeks on 30 dry-skinned elderly volunteers, women aged between 48 and 59 years, with moderate xerosis and photoageing. Surface skin lipids, skin hydration and MDA determination were topically detected by 3C System. ROS was evaluated on the blood serum and on IL-3 stimulated human leukocytes by ROS Meter System at 505 nm. All the subjects applied twice a day for 2 months a nanocolloidal gel and/or take a diet supplement by oral route at the quantity of two capsules per day. All the formulations used were antioxidant-enriched (ascorbic acid, tocopherol, alpha-lipoic acid, melatonin, emblica). Results: Oxidative stress and consequently lipids peroxidation decreased from 30 to 40% (P < 0.005) in blood serum of all the subjects treated with antioxidant compounds topically and by oral route. Both free radicals recovered in blood serum and on skin (in vivo) and ROS induced by irradiation of leucocytes with UVB light (in vitro), appear sensibly lower in subjects antioxidant-treated. Conclusions: From the obtained data, it seems possible to conclude that all the compounds used play interesting role as topical and systemic photoprotectants, thanks to their interesting antioxidant property. Moreover, the antioxidant treatment seems to be a promising therapeutic approach also in reducing the oxidative stress of people affected by photoaging.     

新营养补充剂的抗抑郁效应及其应用进展

在讨论抑郁症的生物根源、症状及抗抑郁药的基础上,综述新营养补充剂——Empowerplus的组成、主要成分、抗抑郁效应的作用机制及其应用进展。     

Clinical and instrumental evaluation of a food supplement in improving skin hydration

Topically applied cosmetic products can be helpful in improving skin hydration. The study shows how oral supplementation could be helpful in improving and preventing the skin dehydration. A total of 32 healthy female volunteers entered the study. Of which, 16 were treated with a food supplement based on vegetable ceramides, amino acids, fish cartilage, antioxidants and essential fatty acids for 40 days and 16 with placebo. The results of the clinical and instrumental evaluations carried out in this study, have highlighted how the active treatment is effective in improving skin hydration and in reducing the cutaneous smoothness and roughness and the depth of furrows, in comparison to the placebo. In fact, concerning several important parameters, as stratum corneum hydration and skin roughness, the improvement measured exceeded 25%. We therefore suggest that a combination of treatments (oral and topical) can be more effective in improving skin hydration.     

Current status of biobased and biodegradable food packaging materials: Impact on food quality and effect of innovative processing technologies

Fossil-based plastic materials are an integral part of modern life. In food packaging, plastics have a highly important function in preserving food quality and safety, ensuring adequate shelf life, and thereby contributing to limiting food waste. Meanwhile, the global stream of plastics into the oceans is increasing exponentially, triggering worldwide concerns for the environment. There is an urgent need to reduce the environmental impacts of packaging waste, a matter raising increasing consumer awareness. Shifting part of the focus toward packaging materials from renewable resources is one promising strategy. This review provides an overview of the status and future of biobased and biodegradable films used for food packaging applications, highlighting the effects on food shelf life and quality. Potentials, limitations, and promising modifications of selected synthetic biopolymers; polylactic acid, polybutylene succinate, and polyhydroxyalkanoate; and natural biopolymers such as cellulose, starch, chitosan, alginate, gelatine, whey, and soy protein are discussed. Further, this review provides insight into the connection between biobased packaging materials and innovative technologies such as high pressure, cold plasma, microwave, ultrasound, and ultraviolet light. The potential for utilizing such technologies to improve biomaterial barrier and mechanical properties as well as to aid in improving overall shelf life for the packaging system by in-pack processing is elaborated on.     

餐饮食品营养成分影响因素分析

目的 对餐饮食品中营养成分的影响因素进行调查分析,为推广餐饮食品营养标识应用,助力营养健康食堂和营养健康餐厅建设,营造更健康的饮食环境提供理论依据。方法 在具有南北餐饮特色的北京和舟山两地组织当地食品营养及餐饮行业专业技术人员进行专题小组访谈,对访谈结果进行整理分析。结果 参与访谈人员普遍认为我国餐饮食品营养成分影响因素主要在原材料、前处理、烹饪方式及烹饪条件等方面。结论 对餐饮食品营养成分影响因素的了解将有助于进一步展开针对性研究,帮助餐饮业提升餐饮食品营养品质,不断改善居民的膳食生活质量,提高国民营养健康水平,助力健康中国建设。     

Optimization of the antioxidant capacity of a mixture of carotenoids and α-tocopherol in the development of a nutritional supplement

The objective of the present study was to determine the interaction between α-tocopherol, β-carotene and lycopene in the formulation of a nutritional supplement using a “simplex-centroid” design and response surface methodology (RSM). Mixtures containing different proportions of each compound had their antioxidant activity (AOA) evaluated by the percent inhibition of spontaneous autoxidation. The regression model fitted to the experimental data demonstrated that the linear terms and only the quadratic terms containing the lycopene variable had a significant impact on the AOA response. A validation assay for the model was performed. The observed value obtained experimentally for AOA did not differ significantly from the value estimated by the adjusted model. The results showed that no synergism occurred between the three compounds when rat brain homogenate was used as the oxidable substrate, and also suggested that RSM can be applied to estimate the behavior of mixed ingredients in nutritional supplements.     

The food behavior of schoolchildren in the GDR and the Lithuanian SSR

Food behavior was studied in schoolchildren of the same age in the GDR (1602) and in the Lithuanian SSR (720 schoolchildren). The examinee represented schoolchildren from towns, regional centres and rural areas. Food behavior of schoolchildren, aged 11-13 years, in the GDR and the Lithuanian SSR is practically similar, but it has been noted that more children in the GDR receive a second breakfast, while in the Lithuanian SSR more children receive afternoon snacks. The schoolchildren should be taught the principles of the rational nutrition during their studies. Active sanitary propaganda is necessary for learning the principles of sound way of life including the principles of rational nutrition.     

Effects of nutritional status on serum fetuin-A level

Abstract

Fetuin-A is a glycoprotein structured molecule which is mostly released by the liver. As a multifunctional protein, fetuin-A has positive effects on health such as calcification, cardiovascular diseases and tumor development processes with various mechanisms, whereas it plays a negative role in the processes of obesity, diabetes and fatty liver disease. There are a large number of studies reporting that serum fetuin-A levels are affected by several dietary factors. It is reported in some of these studies that several nutrients increase fetuin-A release, while some others have adverse effects. It is put forward that some nutrients such as dairy products, curcumin, niacin, palmitate, coffee and alcohol consumption decrease fetuin-A level, and dietary omega-3 fatty acids intake may increase fetuin-A concentration. In addition, it is indicated that high blood glucose levels increase hepatic fetuin-A release by activating extracellular signal-regulated kinase 1/2 enzymes and increased plasma free fatty acids do the same effect by increasing NF-_KB activity. Despite these studies in the literature, there is not any review evaluating fetuin-A, chronic diseases and nutrition together. Therefore, in this study, the relationship between serum fetuin levels and some diseases and the effects of nutrients on fetuin A levels were investigated with possible mechanisms.