浅谈食物营养与膳食平衡

食物营养是人类生存的基本条件，更是反映一个国家经济水平和人民生活质量的重要指标。当今时下，随着人们饮食结构的不断调整以及生活质量的提高，绿色食品已成为现代人追求的饮食时尚，而健康餐饮又是目前饮食业的主流，也是目前摆在营养学专家面前探讨的一个新课题。在人们日常的饮食生活当中，食物中的营养与膳食的平衡对人体健康是至关重要的。     

膳食结构演变及分析

人类的膳食结构在自己漫长的食生活历史上不断演变,当世界的主要膳食结构可分为：以动物性食物为主,以动植物食品并重,以植物性食品为主的三种类型,我国目前的膳食结构存在着两类不同的现状,一方面少数地区需要提高膳食质量,另一方面,大,中城市要防止营养过剩,这就要求我们建立有中国特色的合理的膳食结构。     

浅谈合理营养与膳食平衡

随着经济的发展和生活水平的不断提高,人们对营养的要求越来越高,如何吃得科学备受关注,只有合理营养,人体才能健康。食物营养是一日三餐中用以维持人们生命活动所要消化、吸收和利用的各类营养素,而合理营养就是食品在符合卫生要求的前提下,经过合     

新疆膳食结构现状与改善对策

本文分析了新疆不同民族居民的膳食结构现状与疾病的关系，从而按90年代我国膳食结构改革的目标，提出改善的对策。     

我国居民膳食营养不平衡原因分析及对策

根据1982年、1992年、2002年我国居民营养健康调查结果，分析了我国居民膳食结构的变化及原因，指出解决目前我国膳食营养中存在的主要问题及为改善居民营养健康状况的一些对策。     

Dietary polyphenols and the prevention of diseases

Polyphenols are the most abundant antioxidants in the diet and are widespread constituents of fruits, vegetables, cereals, dry legumes, chocolate, and beverages, such as tea, coffee, or wine. Experimental studies on animals or cultured human cell lines support a role of polyphenols in the prevention of cardiovascular diseases, cancers, neurodegenerative diseases, diabetes, or osteoporosis. However, it is very difficult to predict from these results the effects of polyphenol intake on disease prevention in humans. One of the reasons is that these studies have often been conducted at doses or concentrations far beyond those documented in humans. The few clinical studies on biomarkers of oxidative stress, cardiovascular disease risk factors, and tumor or bone resorption biomarkers have often led to contradictory results. Epidemiological studies have repeatedly shown an inverse association between the risk of myocardial infarction and the consumption of tea and wine or the intake level of some particular flavonoids, but no clear associations have been found between cancer risk and polyphenol consumption. More human studies are needed to provide clear evidence of their health protective effects and to better evaluate the risks possibly resulting from too high a polyphenol consumption.     

Dietary fruits and vegetables and cardiovascular diseases risk

Diet is likely to be an important determinant of cardiovascular disease (CVD) risk. In this article, we will review the evidence linking the consumption of fruit and vegetables and CVD risk.

The initial evidence that fruit and vegetable consumption has a protective effect against CVD came from observational studies. However, uncertainty remains about the magnitude of the benefit of fruit and vegetable intake on the occurrence of CVD and whether the optimal intake is five portions or greater. Results from randomized controlled trials do not show conclusively that fruit and vegetable intake protects against CVD, in part because the dietary interventions have been of limited intensity to enable optimal analysis of their putative effects.

The protective mechanisms of fruit and vegetables may not only include some of the known bioactive nutrient effects dependent on their antioxidant, anti-inflammatory, and electrolyte properties, but also include their functional properties, such as low glycemic load and energy density. Taken together, the totality of the evidence accumulated so far does appear to support the notion that increased intake of fruits and vegetables may reduce cardiovascular risk. It is clear that fruit and vegetables should be eaten as part of a balanced diet, as a source of vitamins, fiber, minerals, and phytochemicals.

The evidence now suggests that a complicated set of several nutrients may interact with genetic factors to influence CVD risk. Therefore, it may be more important to focus on whole foods and dietary patterns rather than individual nutrients to successfully impact on CVD risk reduction.

A clearer understanding of the relationship between fruit and vegetable intake and cardiovascular risk would provide health professionals with significant information in terms of public health and clinical practice.     

Dietary fatty acids linking postprandial metabolic response and chronic diseases

Chronic diseases are by far one of the main causes of mortality in the world. One of the current global recommendations to counteract disability and premature death resulting from chronic diseases is to decrease the consumption of energy-dense high-fat diets, particularly those rich in saturated fatty acids (SFA). The most effective replacement for SFA in terms of risk factor outcomes for chronic disease are polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA). The biochemical basis for healthy benefits of such a dietary pattern has been widely evaluated under fasting conditions. However, the increasing amount of data available from multiple studies suggest that the postprandial state, i.e., "the period that comprises and follows a meal", plays an important, yet underappreciated, role in the genesis of numerous pathological conditions. In this review, the potential of MUFA, PUFA, and SFA to postprandially affect selected metabolic abnormalities related to chronic diseases is discussed.     

The powerful story against cardiovascular diseases: Dietary factors

Cardiovascular diseases are the underlying cause of most deaths worldwide, and they are expected to rise in the following years. Cardiovascular diseases include diseases that affect the heart, cerebral, and peripheral vessels, resulting in ischemia. On the basis of cardiovascular disease pathophysiology, there are lipoprotein metabolism abnormalities, oxidative stress, chronic inflammation, endothelium damage, and atherothrombosis. Modifiable risk factors for cardiovascular health and diseases are blood pressure, blood lipid profile, oxidative stress, inflammation, and other factors (smoking, obesity, diabetes mellitus). Atherosclerotic plaque development, vascular calcification, and vascular stiffness are caused by a long-term endothelial dysfunction and inflammatory response, which can be prevented and controlled by the diet. Fat and cholesterol are the commonly considered dietary factors in the association of the nutrition and the cardiovascular disease, although other macronutrients, especially carbohydrates and proteins, also have major effects. Nowadays, other macronutrients and micronutrients (minerals and vitamins) have roles in regulating the indicated processes (blood pressure, calcification, oxidative stress, inflammation, etc.) in cardiovascular disease prognosis. Other dietary compounds (sterols, stanols, polyphenols, carotenoids, etc.) that exist in small amounts in foods might have a role in regulating these mechanisms as well. There are also new insights about walnuts, garlic, ginger, and hawthorn as parts of a healthy diet against cardiovascular diseases. So far, there have not appeared any reviews that combine the impact of a wide variety of dietary components on cardiovascular diseases. Thus, the novel nutritional targets and interventions that focus on nutrients and other dietary compounds on potential mechanisms underlying cardiovascular diseases are discussed in this review.     

Dietary nutrition and gut microflora: A promising target for treating diseases

BackgroundThe human gastrointestinal tract harbors hundreds of millions of microorganisms, which create a unique environment for each individual. The relationship between gut microflora and human health is being increasingly recognized, and the influence of gut microbiota on the host is well characterized, including maintenance of the body's energy metabolism and immune system. Gut microbiota have been found to be closely linked to obesity, allergy, diabetes, cancer or even some mental diseases. Diet can strongly affect human health, partly by modulating gut microbial composition and quantity.Scope and ApproachIn this review, the relationship between diseases and gut microbes and the effect of different dietary components on gut microflora are summarized. This paper mainly focused on how different diet structure such as high intake of dietary fiber, fat, protein and alcohol etc. may exert impact on specific diseases via gut microflora.Key findings and conclusionsSpecific diseases can be strongly affected by gut microflora and dietary nutrition plays an important role in affecting the composition of gut microflora for individuals since their birth. A bridge between diets and multiple diseases via gut microbiota is built in this review, hopefully to provide references for further investigation of how the diets affect human health via gut microflora and for development of functional foods targeting on gut microflora to solve some health problems.     

Dietary patterns and the risk of obesity,type 2 diabetes mellitus,cardiovascular diseases,asthma, and neurodegenerative diseases

Diet and lifestyle play a significant role in the development chronic diseases; however the full complexity of this relationship is not yet understood. Dietary pattern investigation, which reflects the complexity of dietary intake, has emerged as an alternative and complementary approach for examining the association between diet and chronic diseases. Literature on this association has largely focused on individual nutrients, with conflicting outcomes, but individuals consume a combination of foods from many groups that form dietary patterns. Our objective was to systematically review the current findings on the effects of dietary patterns on chronic diseases. In this review, we describe and discuss the relationships between dietary patterns, such as the Mediterranean, the Dietary Approach to Stop Hypertension, Prudent, Seventh-day Adventists, and Western, with risk of obesity, type-2 diabetes mellitus, cardiovascular diseases, asthma, and neurodegenearive diseases. Evidence is increasing from both observational and clinical studies that plant-based dietary patterns, which are rich in fruits, vegetables, and whole grains, are valuable in preventing various chronic diseases, whereas a diet high in red and processed meat, refined grains and added sugar seems to increase said risk. Dietary pattern analysis might be especially valuable to the development and evaluation of food-based dietary guidelines.     

Variation in nutrients formulated and nutrients supplied on 5 California dairies

Computer models used in ration formulation assume that nutrients supplied by a ration formulation are the same as the nutrients presented in front of the cow in the final ration. Deviations in nutrients due to feed management effects such as dry matter changes (i.e., rain), loading, mixing, and delivery errors are assumed to not affect delivery of nutrients to the cow and her resulting milk production. To estimate how feed management affects nutrients supplied to the cow and milk production, and determine if nutrients can serve as indexes of feed management practices, weekly total mixed ration samples were collected and analyzed for 4 pens (close-up cows, fresh cows, high-milk-producing, and low-milk-producing cows, if available) for 7 to 12 wk on 5 commercial California dairies. Differences among nutrient analyses from these samples and nutrients from the formulated rations were analyzed by PROC MIXED of SAS (SAS Institute Inc., Cary, NC). Milk fat and milk protein percentages did not vary as much [coefficient of variation (CV) = 18 to 33%] as milk yield (kg; CV = 16 to 47 %) across all dairies and pens. Variability in nutrients delivered were highest for macronutrient fat (CV = 22%), lignin (CV = 15%), and ash (CV = 11%) percentages and micronutrients Fe (mg/kg; CV = 48%), Na (%; CV = 42%), and Zn (mg/kg; CV = 38%) for the milking pens across all dairies. Partitioning of the variability in random effects of nutrients delivered and intraclass correlation coefficients showed that variability in lignin percentage of TMR had the highest correlation with variability in milk yield and milk fat percentage, followed by fat and crude protein percentages. But, variability in ash, fat, and lignin percentages of total mixed ration had the highest correlation with variability in milk protein percentage. Therefore, lignin, fat, and ash may be the best indices of feed management to include effects of variability in nutrients on variability in milk yield, milk fat, and milk protein percentages in ration formulation models.