Food and Agricultural Organization of the United Nations PA N I S F I A T G u id e in e s o n fo o d fo r tific atio n w th m ic r o n u tr ie n ts Interest in micronutrient malnutrition has increased greatly over the last few years. One of the main reasons is the realization that micronutrient malnutrition contributes substantially to the global burden of disease. Furthermore, although micronutrient malnutrition is more frequent and severe in the developing world and among disadvantaged populations, it also represents a public health problem in some industrialized countries. Measures to correct micronutrient deficiencies aim at ensuring consumption of a balanced diet that is adequate in every nutrient. Unfortunately, this is far from being achieved everywhere since it requires universal access to adequate food and appropriate dietary habits. Food fortification has the dual advantage of being able to deliver nutrients to large segments of the population without requiring radical changes in food consumption patterns.

Guidelines on food fortification with micronutrients

This review covers current knowledge of selenium in the environment, dietary intakes, metabolism and status, functions in the body, thyroid hormone metabolism, antioxidant defense systems and oxidative metabolism, and the immune system. Selenium toxicity and links between deficiency and Keshan disease and Kashin-Beck disease are described. The relationships between selenium intake/status and various health outcomes, in particular gastrointestinal and prostate cancer, cardiovascular disease, diabetes, and male fertility, are reviewed, and recent developments in genetics of selenoproteins are outlined. The rationale behind current dietary reference intakes of selenium is explained, and examples of differences between countries and/or expert bodies are given. Throughout the review, gaps in knowledge and research requirements are identified. More research is needed to improve our understanding of selenium metabolism and requirements for optimal health. Functions of the majority of the selenoproteins await characterization, the mechanism of absorption has yet to be identified, measures of status need to be developed, and effects of genotype on metabolism require further investigation. The relationships between selenium intake/status and health, or risk of disease, are complex but require elucidation to inform clinical practice, to refine dietary recommendations, and to develop effective public health policies.

Selenium in human health and disease.

An outbreak of a novel coronavirus (COVID-19 or 2019-CoV) infection has posed significant threats to international health and the economy. In the absence of treatment for this virus, there is an urgent need to find alternative methods to control the spread of disease. Here, we have conducted an online search for all treatment options related to coronavirus infections as well as some RNA-virus infection and we have found that general treatments, coronavirus-specific treatments, and antiviral treatments should be useful in fighting COVID-19. We suggest that the nutritional status of each infected patient should be evaluated before the administration of general treatments and the current children's RNA-virus vaccines including influenza vaccine should be immunized for uninfected people and health care workers. In addition, convalescent plasma should be given to COVID-19 patients if it is available. In conclusion, we suggest that all the potential interventions be implemented to control the emerging COVID-19 if the infection is uncontrollable.

https://www.onlinelibrary.wiley.com/doi/epdf/10.1002/jmv.25707

Potential Interventions for Novel Coronavirus in China: A Systematic Review

It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of foods and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This updated position paper couples a rigorous, systematic, evidence-based analysis of nutrition and performance-specific literature with current scientific data related to energy needs, assessment of body composition, strategies for weight change, nutrient and fluid needs, special nutrient needs during training and competition, the use of supplements and ergogenic aids, nutrition recommendations for vegetarian athletes, and the roles and responsibilities of sports dietitians. Energy and macronutrient needs, especially carbohydrate and protein, must be met during times of high physical activity to maintain body weight, replenish glycogen stores, and provide adequate protein to build and repair tissue. Fat intake should be sufficient to provide the essential fatty acids and fat-soluble vitamins, as well as contribute energy for weight maintenance. Although exercise performance can be affected by body weight and composition, these physical measures should not be a criterion for sports performance and daily weigh-ins are discouraged. Adequate food and fluid should be consumed before, during, and after exercise to help maintain blood glucose concentration during exercise, maximize exercise performance, and improve recovery time. Athletes should be well hydrated before exercise and drink enough fluid during and after exercise to balance fluid losses. Sports beverages containing carbohydrates and electrolytes may be consumed before, during, and after exercise to help maintain blood glucose concentration, provide fuel for muscles, and decrease risk of dehydration and hyponatremia. Vitamin and mineral supplements are not needed if adequate energy to maintain body weight is consumed from a variety of foods. However, athletes who restrict energy intake, use severe weight-loss practices, eliminate one or more food groups from their diet, or consume unbalanced diets with low micronutrient density, may require supplements. Because regulations specific to nutritional ergogenic aids are poorly enforced, they should be used with caution, and only after careful product evaluation for safety, efficacy, potency, and legality. A qualified sports dietitian and in particular in the United States, a Board Certified Specialist in Sports Dietetics, should provide individualized nutrition direction and advice subsequent to a comprehensive nutrition assessment.

Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance.

Objective: The intent of this review is to evaluate the scientific evidence for the assessment of adequacy of selenium status and of the requirements for selenium. From this evidence, attempts have been made to define levels of plasma selenium and dietary selenium intake, which could be used for the assessment of deficiency or adequacy of selenium status. Method: The first section briefly reviews the methods for assessment of selenium status. The second section outlines the requirements for selenium based on a number of criteria, and how these have been translated into recommended intakes of selenium. In the final section, levels of plasma selenium and dietary intake based on different criteria of adequacy have been proposed. Results and conclusion: The minimum requirement for selenium is that which prevents the deficiency disease, Keshan disease. The recommended intakes of selenium have been calculated from the requirement for optimum plasma glutathione peroxidase (GPx) activity that must, because of the hierarchy of selenoproteins, also take account of the amounts needed for normal levels of other biologically necessary selenium compounds. Whether optimal health depends upon maximization of GPx or other selenoproteins, however, has yet to be resolved, and the consequences of less-than-maximal GPx activities or mRNA levels need investigation. Intakes, higher than recommended intakes, and plasma selenium concentrations that might be protective for cancer or result in other additional health benefits have been proposed. There is an urgent need for more large-scale trials to assess any such beneficial effects and to provide further data on which to base more reliable estimates for intakes and plasma selenium levels that are protective.

Assessment of requirements for selenium and adequacy of selenium status: a review

SPECIFIC AIMTo determine the effect of a deficiency of the nutritionally essential trace element selenium (Se) in mice infected with influenza virus on lung pathology, viral titers, and the host im...

Selenium deficiency increases the pathology of an influenza virus infection.

An in vitro method for the estimation of iron bioavailability was subjected to an interlaboratory trial The method involved a simulated gastrointestinal digestion using pepsin for the gastric stage followed by pancreatin and bile salts for the intestinal stage The proportion of iron diffused through a semipermeable membrane (molecular mass cut-off 10 kDa) was used to measure the iron dialysability An interlaboratory trial between nine laboratories was conducted to evaluate the repeatability and reproducibility of the agreed method The reproducibility of the method among the participating laboratories was 20-30% and depended on the content of dialysable iron Several factors contributing to the variation in the in vitro dialysability among laboratories are discussed The pH adjustment in the intestinal digestion was identified as one of the critical parameters The present in vitro method was used to evaluate the iron dialysability from three meals The dialysability data were in reasonable agreement with human absorption data The usefulness of the in vitro dialysability method is discussed

Interlaboratory trial on the determination of the In Vitro iron dialysability from food

The present study was designed to determine the apparent absorption and retention of the inorganic Se compounds SeO 3 2 and SeO 4 2- , which are commonly used for Se fortification of clinical nutrition products and infant formulas. Ten healthy men were fed a milk-based formula labelled with 40 μg Se as 74SeO32 or 76 SeO 4 2 on two consecutive days using a randomised crossover design. Se stable-isotope analysis of 9 d complete collections of urine and faeces was used to calculate apparent Se absorption and retention. Se retention from 74 SeO 3 2 (41.0 (SD 8.4) %) and from 76 SeO 4 2- (46.0 (SD 7.9) %) was not significantly different (P > 0.05). However, Se absorption was significantly higher from SeO 4 2 than from SeO 3 2 (91.3 (SD 1.4) % ν. 50.2 (SD 7.8) %, P < 0.05). Urinary excretion of the administered dose was 9.2 (SD 1.8) % for 74 SeO 3 2- and 45.3 (SD 8.2) % for 76 SeO 4 2- (P < 0.05). Urinary Se excretion kinetics differed significantly for the two Se compounds; 90 % of the total urinary Se was excreted after 121 h for 74 SeO 3 2 and after 40 h for 76 SeO 4 2 (P < 0.05). These results suggest that although Se absorption and urinary excretion differ for SeO 3 2- and SeO 4 2 both Se compounds are equally well retained when administered at a relatively low dose (40 μg Se). The nutritional impact of Se fortification of foods would thus be expected to be similar when SeO 4 2 or SeO 3 2 are used.

/pdf/selenium-absorption-and-retention-from-a-selenite-or-wkz3i3r7x8.pdf

Selenium absorption and retention from a selenite- or selenate-fortified milk-based formula in men measured by a stable-isotope technique.

Infant formulas based on soyabean protein isolate are often used as an alternative to cows'-based formulas. However, the presence of phytic acid in soya formulas has raised concern about the absorption of trace elements and minerals from these products. The aim of the present study was to evaluate mineral and trace element absorption from regular and dephytinised soya formula in healthy infants. Soyabean protein isolate with a relatively low native content of phytic acid was used for production of a regular soya formula (300 mg phytic acid/kg liquid formula) and an experimental formula was based on dephytinised soya protein isolate (<6 mg phytic acid/kg liquid formula). Using a crossover study design, apparent mineral and trace element absorptions were measured by a stable isotope technique based on 72 h faecal excretion of non-absorbed stable isotopes (Zn, Fe, Cu and Ca) and by the chemical balance technique (Mn, Zn, Cu and Ca) in nine infants (69-191 d old). Fe absorption was also measured by erythrocyte incorporation 14 d after intake. The results from the present study demonstrated that Zn absorption, measured by a stable isotope technique, was significantly greater after dephytinisation (mean value 16.7 v. 22.6 %; P=0.03). No other statistically significant differences between the two formulas were observed. The nutritional benefit of dephytinisation was marginal in the present study. Based on these results, the use of soyabean protein isolate with low native content of phytic acid should be promoted for production of soya formulas and adequate addition of ascorbic acid to enhance Fe absorption should be ensured in the products.

/pdf/dephytinisation-of-soyabean-protein-isolate-with-low-native-4c6popeyht.pdf

Dephytinisation of soyabean protein isolate with low native phytic acid content has limited impact on mineral and trace element absorption in healthy infants

Over the last decade a sustained interest in vitamin and trace element nutrition and metabolism in relation with athletic performance has been developed. The general belief is that physical activity requires a high micronutrient intake to enable improved performance. The present book presents a critical overview on the role of vitamins and trace elements in sports nutrition. The term sports nutrition covers a broad range of parameters affecting sport performance; namely physical and mental performance, immune response, antioxidant protection and healing muscular injuries. Most vitamins and trace elements are discussed individually in separate chapters. Each chapter is headed by an introduction on nutritional and biochemical properties of the micronutrient, prior to addressing its role on sports nutrition. Micronutrients with reported evidence on affecting physical performance are discussed extensively, referring to multiple scienti®c data. The chapter on `Other substances in Foods' is particularly useful as it reviews the current scienti®c status on performance implications of `newer boosters' such as choline, carnitine and taurine. Each chapter is concluded with a straightforward summary and areas where research is still needed are highlighted. The chosen set-up combines the interests of both for the professional and the interested reader without speci®c knowledge on micronutrients. The great variability in the effect of the different micronutrients on performance and the way the information is presented, makes the book, as with many multi-authored texts, sometimes dif®cult to read. On the other hand it is the ®rst textbook clearly covering the effect of a broad range of micronutrients on sports performance. It critically evaluates the multiple studies on the role vitamins and minerals play in sports nutrition, demysti®es the effect of certain micronutrient supplements and highlights research gaps. In summary, `Sports Nutrition: Vitamins and Trace Elements', is an excellent textbook for all those who want to be updated on the role of micronutrients on sports performance.

Peter Van Dael

Papers

Selenium deficiency increases the pathology of an influenza virus infection.

Interlaboratory trial on the determination of the In Vitro iron dialysability from food

Selenium absorption and retention from a selenite- or selenate-fortified milk-based formula in men measured by a stable-isotope technique.

Dephytinisation of soyabean protein isolate with low native phytic acid content has limited impact on mineral and trace element absorption in healthy infants

Sports Nutrition: Vitamins and Trace Elements