Fortifying Micronutrient Supplementation in India: Indian Expert consensus.

Micronutrients play a key role in human health, being involved in energy metabolism, immunity, cellular functioning, growth, and development. Deficiencies in micronutrients occur in individuals of all ages due to several factors, including inadequate diets, disease states, and overweight/obesity. Guidelines from the Indian Council of Medical Research (ICMR) National Institute of Nutrition (NIN) Expert Group on Nutrient Requirements for Indians (2023) have specified the Recommended Dietary Allowances (RDA) for macronutrients and micronutrients. In addition, a healthy diet is crucial for overall health and should be the first step toward addressing micronutrient deficiencies. When diet is inadequate, micronutrient supplements can be provided to compensate. An expert panel of Indian doctors was convened to develop a pathway toward micronutrient supplementation among the Indian population. This Consensus Statement recognizes that different populations have varying needs for specific micronutrients, and ensuring adequate intake of such micronutrients can improve health outcomes. The panel provided recommendations for dietary practices and micronutrient supplementation when diet is inadequate. Addressing micronutrient deficiencies at the primary care level can prevent chronic deficiencies and their consequences. This Consensus Statement can serve as a primer for physicians to monitor and address deficiencies and thus help individuals maintain their health.

Beef Consumption Is Associated with Higher Intakes and Adequacy of Key Nutrients in Older Adults Age 60+ Years: National Health and Nutrition Examination Survey 2011-2018 Analysis.

Beef is an important source of high-quality protein and several micronutrients, including iron, zinc, and B vitamins. We determined beef intake and its relationship with intakes of nutrients and their adequacy using 24 h dietary recall data from 5868 older adults. Usual intakes from foods were determined using the National Cancer Institute method, and the percent of the population below the estimated average requirement or above adequate intake was estimated. A high percentage of older adults did not meet nutrient recommendations for vitamin D (96%), choline (96%), vitamin E (84%), potassium (70%), calcium (63%), magnesium (60%), vitamin C (46%), vitamin A (39%), zinc (21%), vitamin B6 (19%), and folate (15%). About 68% of older adults were beef consumers with a mean intake of 56 g/day. Beef consumers had higher (p < 0.05) intakes of energy, protein, calcium, iron, phosphorus, selenium, sodium, zinc, thiamin, riboflavin, niacin, vitamin B12, and choline, and a higher (p < 0.05) proportion met nutrient recommendations for protein, calcium, copper, zinc, thiamin, folate, and vitamin B12 than non-consumers. Consumers of fresh, ground, and processed beef also had generally higher intakes and lower inadequacies of many nutrients depending on the beef type. In conclusion, older adults generally had poor nutrient adequacy from their diets, while beef consumers had higher nutrient intakes and adequacy for certain key nutrients, which are inherently generally available from beef or from foods consumed with beef.

LLL 44 - Module 3: Micronutrients in Chronic disease.

Micronutrients (MN), i.e. trace elements and vitamins, are essential organic molecules, which are required in the diet in relatively small amounts in any form of nutrition (oral, enteral, parenteral). The probability of MN depletion or deficiencies should be considered in all chronic illnesses, especially in those that can interfere with intake, digestion, or intestinal absorption. Low socio-economic status and food deprivation are recognized as the most prevalent reasons for MN deficiencies world-wide. Elderly multimorbid patients with multimodal therapy, as well as patients with long-lasting menu restrictions, are at high risk for both disease related malnutrition as well as multiple MN deficiencies, needing careful specific follow-up. The importance of monitoring MN blood levels along with CRP is essential for optimal care. Drug interactions are also highlighted. In patients with chronic conditions depending on medical nutrition therapy, the provision of adequate dietary reference intakes (DRI) of MN doses and monitoring of their adequacy belongs to standard of care.

Pulmonary rehabilitation: A cohort study assessing the effectiveness of a multi-professional nutrition intervention.

BACKGROUND: Limited benefit of pulmonary exercise rehabilitation has been associated with fulfilment of energy and protein requirements. OBJECTIVES: The aim was to enhance dietary intake towards requirements and to maintain changes after a pulmonary rehabilitation program. METHODS: This single arm intervention study included multidisciplinary focus on nutrition and three sessions of individual dietary counselling during a 10-week pulmonary exercise rehabilitation in five municipalities centers. Data were collected at baseline (P0), at the end of intervention (P1) and for two municipalities at three months post intervention (P2). RESULTS: Of the 111 included participants, (mean age 70.8 (±9)) 99 (89%) completed the rehabilitation including the three individual dietary counselling's. A very large variation in body composition including body mass index and exercise abilities was found. Protein intake improved from 64 (±22 g) (P0) to 88 (±25 g) (P1) (p < 0.001) and energy intake from 1676 (±505 kcal) (P0) to 1941 (±553 kcal) (p < 0.001) (P1) and Muscle Mass Index increased from 10.6 (±3.2) (P0) to 10.9 (±3.2) (P1) (p = 0.007); number of 30 s chair stand test improved from 10.9 (±2.8) repetitions (P0) to 14.1 (±4.3) repetitions (P1) (p < 0.001), distance in six-minut walking test improved from 377.2 (±131.2 m) (P0) to 404.1 (±128.6 m) (P1) (p < 0.001). Two municipalities completed the three months follow-up. For those, dietary improvements remained stable, including protein intake. CONCLUSION: Including three sessions of dietary counselling in a multi-professional effort was associated with improved individualized dietary intake, as well as physical function. Benefits remained almost unchanged after three months. Improvements in function could not be fully explained by improved intakes.

Differences in perceived energy and macronutrient requirements across divisions in NCAA athletes.

BACKGROUND: Sports nutrition is an impactful component to sports performance. The purpose of the current study was to investigate the sports nutrition knowledge of National Collegiate Athletic Association collegiate athletes and assess self-reported perceived requirements for energy and macronutrient intake. A secondary aim was to evaluate the awareness of physical and emotional perceptions associated with mindful eating. METHODS: Participants included NCAA Division I (DI, n = 45), II (DII, n = 31), and III (DIII, n = 47) athletes. Athletes completed a validated questionnaire designed to assess sports nutrition knowledge and were asked questions about their perceived dietary energy and macronutrient requirements. Daily energy intake values were calculated using a recommended relative energy intake value of 40, 50, and 60 kcal/kg/day for low, moderate, and high activity levels, respectively. Carbohydrate recommendations were calculated using 4, 6, and 8 g/kg/day, protein recommendations were calculated using relative intakes of 1.4, 1.6, and 1.8 g/kg/day, and fat recommendations were calculated from a relative percentage of total predicted daily energy requirements, equating to 15, 25, and 30% of daily energy. Additionally, athletes completed a questionnaire to assess mindfulness regarding eating habits. RESULTS: Overall, athletes answered 45.5 ± 13.5% of questions correctly on the nutrition questionnaire with significant differences observed between male (48.6 ± 13.6%) and female athletes (43.6 ± 13.2%; p = 0.044), as well as significant differences observed between DI athlete scores (38.8 ± 14.1%) and DII athletes (47.7 ± 11.4%; p = 0.002), and DI athletes and DIII athletes (51.71 ± 11.83%; p = <0.001). All athletes significantly (p < 0.001) underestimated daily energy intake requirements (female, 2,112 ± 575 kcal/day; male, 3,283 ± 538 kcal/day). The mindfulness eating habits total score was significantly higher in male athletes (65.1 ± 6.5) compared to female athletes (60.9 ± 9.5; p = 0.009). CONCLUSIONS: Division I, II, and III collegiate athletes have poor sports nutrition knowledge, with Division I athletes having exhibited lower scores compared to Division II and III athletes on the sports nutrition knowledge questionnaire. Athletes from all levels of collegiate sports underestimated their energy and macronutrient requirements. Differences in mindful eating habits among female and male athletes were also evident.

The art of establishing mineral tolerances of dogs and cats.

For over six decades, nutritional science has provided well-developed, peer-reviewed nutrient recommendations to support the health of dogs and cats. These guidelines are updated based on new scientifically valid research and appropriate peer-review. Recent regulatory and scientific positions around health issues have resulted in strong opinions and desires for rapid regulatory action surrounding mineral nutrition, but with limited and conflicting scientific evidence. Pet Food Institute nutrition experts have come together to jointly author an article on the complexities of establishing mineral tolerances of dogs and cats to illustrate the limitations in defining mineral tolerances. This discussion covers how mineral requirements were determined, including the opportunities and pitfalls encountered. Scientific councils must review and clarify any proposed changes in conducting mineral nutrition research that might impact complete and balanced foods and surrounding regulations. It is important to clarify the multiple issues in mineral nutrition research and the necessity for thorough evaluation of data while avoiding arbitrary and potentially harmful guidelines.

Dogs and cats are living longer and healthier lives due, in part, to the scientific development of nutritional information. This information has allowed the building of many new types of foods, treats, and supplements that promote life, health, and enjoyment by the pet. There are several organizations that have provided helpful reviews of nutritional data through scientific councils that help identify safe and healthy criteria for all pet food products. These are readily available for those who want to learn more about pet nutrition. For many nutrients, there is a large database of information to help build products. Nutrients that are called macro- or micro-/trace minerals (e.g., sodium, potassium, zinc, copper, etc.) often have more limited information. Recently, strong opinions about pet health as related to mineral nutrition have been shared and robustly communicated without adequate scientific research to support the hypotheses. This has led to misinformation, concerns, and fear. To safeguard the health of companion animals and provide assistance to regulatory bodies regarding the nutritional welfare of dogs and cats, scientific panels have come together from industry, government, and academia to review, approve, and challenge nutritional guidelines. This overview provides the reader context into the rigor needed to establish safe mineral tolerances for dogs and cats.

Protein Requirements for Maximal Muscle Mass and Athletic Performance Are Achieved with Completely Plant-Based Diets Scaled to Meet Energy Needs: A Modeling Study in Professional American Football Players.

American football players consume large quantities of animal-sourced protein in adherence with traditional recommendations to maximize muscle development and athletic performance. This contrasts with dietary guidelines, which recommend reducing meat intake and increasing consumption of plant-based foods to promote health and reduce the risk of chronic disease. The capacity of completely plant-based diets to meet the nutritional needs of American football players has not been studied. This modeling study scaled dietary data from a large cohort following completely plant-based diets to meet the energy requirements of professional American football players to determine whether protein, leucine, and micronutrient needs for physical performance and health were met. The Cunningham equation was used to estimate calorie requirements. Nutrient intakes from the Adventist Health Study 2 were then scaled to this calorie level. Protein values ranged from 1.6-2.2 g/kg/day and leucine values ranged from 3.8-4.1 g/meal at each of four daily meals, therefore meeting and exceeding levels theorized to maximize muscle mass, muscle strength, and muscle protein synthesis, respectively. Plant-based diets scaled to meet the energy needs of professional American football players satisfied protein, leucine, and micronutrient requirements for muscle development and athletic performance. These findings suggest that completely plant-based diets could bridge the gap between dietary recommendations for chronic disease prevention and athletic performance in American football players.

Assessment of the prevalence of inadequate iron intakes in premenopausal females based on the reference values of the European Food Safety Authority using cross-sectional food consumption data.

BACKGROUND: The iron intake requirement distribution for premenopausal females is not symmetric, which invalidates the EAR cut-point approach for assessing the prevalence of iron inadequacy. Therefore, Beaton's Full Probability Approach (PA) must be used. Although the PA requires information on the entire iron intake requirement distribution, the European Food Safety Authority (EFSA) only provided the EAR (50th percentile), 90th, 95th (population reference intake), and 97.5th percentiles. OBJECTIVES: This study aimed to reliably estimate the prevalence of iron inadequacy in premenopausal females using the PA, based on the intake requirements established by EFSA, and compare the results with those obtained from the EAR cut-point method. METHODS: Habitual iron intakes were calculated using the statistical program to assess dietary exposure with data from 484 females (20-45 y) from the Dutch National Food Consumption Survey 2012-2016. Iron requirements of EFSA (including additionally obtained information) were applied. Results from the PA were compared to results obtained with the EAR cut-point method. Sensitivity analyses examined the impact of lower iron intake distributions on differences in estimated inadequate intakes between PA and EAR cut-point methods. RESULTS: A 2-fold higher prevalence of iron inadequacy among Dutch premenopausal females was observed when employing the PA compared to the EAR cut-point method, using EFSA's reference values. Sensitivity analysis showed that the EAR cut-point method could also result in large overestimations for populations with lower intake distributions. CONCLUSIONS: This study provided an example of using the PA method by using additionally derived information on the full requirement distribution underlying EFSA's reference values. Results showed once more the unsuitability of the EAR cut-point method to calculate the prevalence of iron inadequacy in premenopausal females. Hence, we recommend that institutions deriving dietary reference values provide all the information needed to use the correct method to determine inadequate intakes in the population.

LLL 44-1 Micronutrients in clinical nutrition: Trace elements.

BACKGROUND: Trace elements are an essential component of metabolism and medical nutrition therapy, with key roles in metabolic pathways, antioxidation, and immunity, which the present course aims at summarizing. RESULTS: Medical nutrition therapy includes the provision of all essential trace elements. The clinical essential issues are summarized for Copper, Iron, Selenium, Zinc, Iodine, Chromium, Molybdenum, and Manganese: the optimal analytical techniques are presented. The delivery of all these elements occurs nearly automatically when the patient is fed with enteral nutrition, but always requires separate prescription in case of parenteral nutrition. Isolated deficiencies may occur, and some patients have increased requirements, therefore a regular monitoring is required. The clinicians should always consider the impact of inflammation on blood levels, mostly lowering them even in absence of deficiency. CONCLUSION: This text summarises the most relevant clinical manifestations of trace element depletion and deficiency, the difficulties in assessing status, and makes practical recommendations for provision for enteral and parenteral nutrition.

Pathways in formulating foods for the elderly.

The growth of the elderly population worldwide is posing significant challenges to human society. The progressive physical and physiological changes occur with aging, including decreased appetite, incomplete digestion, and reduced absorption of nutrients. A common feature of many elderly people's diets is a deficiency in proteins (especially easily digestible ones) and micronutrients (e.g., vitamins, zinc, iron, and calcium). One of the solutions to this problem is the incorporation of these components into suitably texture-modified foods. There is a dearth of products that meet the needs of the elderly with special medical/health conditions such as dysphagia, osteoporosis, diabetes, and cardiovascular disease, as well as those who are in hospital and palliative care. Future research and development of foods for the elderly must address specific dietary needs of different subgroups of elderly people with underlying health conditions. The existence of different physical and physiological stages of the elderly means that their specific dietary requirements must be considered. This review summarizes current knowledge on nutritional requirements including those with underlying health problems and outlines the research and innovation pathways for developing new foods considering nutrition, texture, flavor, and other sensory aspects.

The development of an EU-wide nutrition and physical activity expert knowledge base to support a personalised mobile application across various EU population groups.

A healthy lifestyle comprising regular physical activity and an adequate diet is imperative for the prevention of non-communicable diseases such as hypertension and some cancers. Advances in information computer technology offer the opportunity to provide personalised lifestyle advice directly to the individual through devices such as smartphones or tablets. The overall aim of the PROTEIN project (Wilson-Barnes et al., 2021) was to develop a smartphone application that could provide tailored and dynamic nutrition and physical activity advice directly to the individual in real time. However, to create this mobile health (m-health) smartphone application, a knowledge base of reference ranges for macro-/micronutrient intake, anthropometry, biochemical, physiological and sleep parameters was required to underpin the parameters of the recommender systems. Therefore, the principal aim of this emerging research paper is to describe the process by which experts in nutrition and physiology from the PROTEIN consortium collaborated to develop the nutritional and physical activity requirements, based upon existing recommendations, for 10 separate population groups living within the EU including, but not limited to healthy adults, adults with type 2 diabetes mellitus, cardiovascular disease, excess weight, obesity and iron deficiency anaemia. A secondary aim is to describe the development of a library of 24-h meal plans appropriate for the same groups and also encompassing various dietary preferences and allergies. Overall, the consortium devised an extensive nutrition and physical activity knowledge base that is pertinent to 10 separate EU user groups, is available in 7 different languages and is practically implemented via a library of culturally appropriate, 24-h meal plans.

LLL 44 - 2 - Micronutrients in clinical nutrition: Vitamins.

Vitamins are essential organic molecules, which are required in the diet in relatively small amounts in any form of nutrition (oral, enteral, parenteral). Despite the small amounts that are required, the vitamins are essential both for maintenance of health, growth, and treatment of disease. After reminding about the principal function of all the vitamins, their needs and the clinical consequences of their deficit, the text present some common clinical problems: the impact of inflammation on the assessment of status. The reasons and diseases which cause increased requirements are presented, with the indications to monitoring of blood levels which remain the classical way to assess status in clinical settings. The text summarises the most relevant clinical manifestations of vitamins depletion and deficiency, the difficulties in assessing status, and makes recommendations for provision for medical nutrition therapy.

LLL 44-4 : Micronutrients in acute disease and critical illness.

Micronutrients (MN), i.e. trace elements and vitamins, are essential components of the diet in relatively small amounts in any form of nutrition, with special needs in critically ill patients. Critical illness is characterised by the presence of inflammation and oxidative stress. MNs are tightly involved in antioxidant and immune defences. In addition, some conditions, and treatments result in large losses of biological fluids containing MNs: therefore, acute renal injury requiring renal replacement therapy, acute intestinal failure, and major burns and trauma are at high risk of acute depletion of body stores, and of deficiency. MN requirements are increased above standard DRI. Blood level interpretation is complicated by inflammation: some biomarkers assist the status determination. Due to the acute challenges of critical illness, it of utmost importance to cover the needs to maintain the organism's endogenous immune and antioxidant defences, and capacity to repair tissues. Practical strategies are proposed.

Comparison of energy requirement estimation using activity record or accelerometer with doubly labeled water method in collegiate male sprinters.

BACKGROUND & AIMS: Track and field sprinters must obtain an optimal body composition to improve sprint performance. To successfully change body composition, it is important to evaluate the estimated energy requirements (EER) and fluctuations in total energy expenditure (TEE). However, methods to accurately evaluate the EER and TEE in sprinters have not been fully investigated. The aim of this study was to compare currently used methods with the doubly labeled water (DLW) method, which is currently the gold standard for evaluating EER and TEE. METHODS: Ten male collegiate sprinters participated in the study. We evaluated TEEDLW and compared it with the EER calculated using two equations used by the National Institute of Health and Nutrition (NIHN) and the Japan Institute of Sports Sciences (JISS). In addition, we evaluated the TEE from the activity record (AR) and triaxial accelerometer (ACC). RESULTS: TEEDLW (3172 ± 415 kcal/day) was not significantly different from EERNIHN (p = 0.076) or EERJISS (p = 0.967). In addition, there were no significant differences between TEEDLW and TEEAR (p = 0.218). However, two accelerometer-derived equations used to evaluate TEE were found to have underestimated (2783 ± 377 kcal/day, p < 0.001) and overestimated (3405 ± 369 kcal/day, p = 0.009) the TEE. CONCLUSION: Our results suggest that EERNIHN and EERJISS may be useful in evaluating the EER of collegiate male sprinters on a group basis, and AR may be more accurate than ACC in evaluating the TEE. These results may be helpful when considering nutritional support for male collegiate sprinters.

Nutritional management in critically ill patients with COVID-19: a retrospective multicentre study.

INTRODUCTION: Although nutritional treatment is an established pillar of multidisciplinary care provided in critical illness, there are many concerns regarding this issue in severe COVID-19. This observational, retrospective, multicentre study aimed to analyse the approach to nutritional treatment among selected intensive care units (ICUs) in Poland. MATERIAL AND METHODS: The medical records of 129 patients hospitalized in five units due to respiratory failure following COVID-19 were analysed in terms of nutritional management on the eighth day of the ICU stay. The Harris-Benedict equation (HB), Mifflin St. Jeor equation (MsJ) and ESPEN formula (20 kcal kg -1 body weight) were used to estimate the energy target for each patient, and two ESPEN formulas determined the protein target (1 g kg -1 body weight and 1.3 g kg -1 body weight). RESULTS: Evaluation of nutritional therapy was performed in 129 subjects. The fulfilment of caloric requirement considering the HB, MsJ and ESPEN formula was 66%, 66.7% and 62.5%, respectively. Two clinical centres managed to provide 70% or more of daily caloric requirements. According to the ESPEN formula, the implementation of the protein target was 70%; however, one of the investigated units provided a median of 157% of the protein demand. The nutritional management varied in the preferred route of nutrition administration. Neither method nor grade of nutrition supply influenced biochemical parameters on the 8th day of ICU stay. CONCLUSIONS: Significant differences in nutritional treatment of critically ill COVID-19 patients in Polish ICUs were noted, which underlines the importance of setting up clear guidelines regarding this issue.

Comparison of Australian Football League Women's athletes match day energy and nutrient intake to recommendations.

AIMS: This cross-sectional observational study quantified Australian Football League Women's athletes' match volume, and compared match-day dietary intakes against recommendations. METHODS: Self-report, direct observation, and fluid measurements determined dietary intake (n = 17, 25 ± 4.5 years, 22.8 ± 1.8 kg/m2) on five home match days (early or late starting). Global positioning system software captured match volume. Linear mixed effects models evaluated differences in early versus late match volume and nutrient intakes. Data are presented as mean ± standard deviation. RESULTS: Athletes covered 6712 ± 622 m during matches, with similar numbers of very high-intensity running efforts over equal distances in early and late matches (early vs. late efforts [no.]: 8.5 ± 4.9 vs. 9.5 ± 5.5; distance [m]: 203 ± 127 vs. 212 ± 113). Across all match days, 71% (n = 12) of athletes met their predicted daily energy requirements. However, 82% (n = 14) failed to meet minimum daily carbohydrate recommendations; intake was lower on early compared with late match days (4.7 g/day vs. 5.4 g/kg/day, p = 0.027). On average, no athletes met carbohydrate recommendations in the 2 h prior to a match and only 24% (n = 4) met recommendations during matches. All athletes met post-match carbohydrate and protein requirements. CONCLUSION: Athletes cover large distances during games with frequent bursts of high-intensity running. However, they do not adjust their intake to meet the energy demands of competition, with inadequate fuelling prior to and during matches. These findings emphasise the need for greater athlete education and dietary support to maximise strategic fuelling to optimise athletic performance.

Dietary Lysine Requirements of Older Adults Stratified by Age and Sex.

BACKGROUND: Current recommendation for lysine in older adults, 30 mg/kg/d, is based on young adult data. Evidence suggests that amino acid requirements may differ between young and old adults with both sex and age having an effect in the elderly. OBJECTIVES: This study aimed to define the lysine requirements in healthy older adults using the indicator amino acid oxidation (IAAO) method with L-[1-13C] phenylalanine as the indicator and to compare the derived estimates based on age: 60-69 y and >70 y. METHODS: Fourteen healthy males and 16 healthy females [>60 y, body mass index (BMI) = 26.3 kg/m2] were randomly assigned to receive 3-7 lysine intakes from 10 to 80 mg/kg/d. Subjects were adapted to a standard liquid diet providing 1.0 g/kg/d protein and adequate energy, for 2 d, with indicator oxidation measurements performed on day 3. The rate of release of 13CO2 from the oxidation of L-[1-13C] phenylalanine was measured in breath. A 2-phase linear mixed-effect model, and parametric bootstrap were used to determine mean lysine requirements and the 95% confidence intervals (CIs). The overlap of the 95% CI between the 2 age groups were used to compare the requirement estimates. The null hypothesis was accepted if the interval contained zero. RESULTS: The mean and upper 95% CI of the lysine requirement for females were 32.9 and 40.9 and 46.2 and 53.7 mg/kg/d for those aged 60-69 y and >70 y, respectively. The mean and upper 95% CI of the lysine requirement for the 2 groups of males were not different so was combined to yield a mean and 95% CI of 32.2 and 38.2 mg/kg/d. CONCLUSIONS: To our knowledge, this is the first study to report on the lysine requirement in adults aged >60 y. These results provide a basis from which the adequacy of diets to meet lysine needs of older adults can be assessed. The trial was registered at clinicaltrials.gov as NCT02008955 (https://clinicaltrials.gov/study/NCT02008955).

Review: Aspects of digestibility and requirements for minerals and vitamin D by growing pigs and sows.

Some of the biggest changes in mineral nutrition for pigs that have occurred due to recent research were caused by the understanding that there is a loss of endogenous Ca and P into the intestinal tract of pigs. This resulted in development of the concept of formulating diets based on standardized total tract digestibility (STTD) rather than apparent total tract digestibility because the values for STTD of these minerals are additive in mixed diets. There are, however, no recent summaries of research on digestibility and requirements of macro- and microminerals and vitamin D for pigs. Therefore, the objective of this review was to summarize selected results of research conducted over the last few decades to determine the digestibility and requirements of some minerals and vitamin D fed to sows and growing pigs. Benefits of microbial phytase in terms of increasing the digestibility of most minerals have been demonstrated. Negative effects on the growth performance of pigs of over-feeding Ca have also been demonstrated, and frequent analysis of Ca in complete diets and raw materials is, therefore, recommended. There is no evidence that current requirements for vitamin D for weanling or growing-finishing pigs are not accurate, but it is possible that gestating and lactating sows need more vitamin D than currently recommended. Vitamin D analogs and metabolites such as 1(OH)D3 and 25(OH)D3 have beneficial effects when added to diets for sows in combination with vitamin D3. Recent research on requirements for macrominerals other than Ca and P is scarce, but it is possible that Mg in diets containing low levels of soybean meal is marginal. Some of the chelated microminerals have increased digestibility compared with sulfate forms, and hydroxylated forms of Cu and Zn appear to be superior to sulfate or oxide forms. Likewise, dicopper oxide and Cu methionine hydroxy analog have a greater positive effect on the growth performance of growing pigs than copper sulfate. The requirement for Mn may need to be increased whereas there appears to be no benefits of providing Fe above current requirements. In conclusion, diets for pigs should be formulated based on values for STTD of Ca and P and there are negative effects of providing excess Ca in diets. It is possible vitamin D analogs and metabolites offer benefits over vitamin D3 in diets for sows. Likewise, chelated forms of microminerals or chemical forms of minerals other than sulfates or oxides may result in improved pig performance.

Post-prandial tracer studies of protein and amino acid utilisation: what can they tell us about human amino acid and protein requirements?

Nitrogen balance (NB), the principal methodology used to derive recommendations for human protein and amino acid requirements, has been widely criticised, and calls for increased protein and amino acid requirement recommendations have been made, often on the basis of post-prandial amino acid tracer kinetic studies of muscle protein synthesis, or of amino acid oxidation. This narrative review considers our knowledge of the homeostatic regulation of the FFM throughout the diurnal cycle of feeding and fasting and what can and has been learnt from post-prandial amino acid tracer studies, about amino acid and protein requirements. Within the FFM, muscle mass in well fed weight-stable adults with healthy lifestyles appears fixed at a phenotypic level within a wide range of habitual protein intakes. However homoeostatic regulation occurs in response to variation in habitual protein intake, with adaptive changes in amino acid oxidation which influence the magnitude of diurnal losses and gains of body protein. Post-prandial indicator amino acid oxidation (IAAO) studies have been introduced as an alternative to NB and to the logistically complex 24 h [13C-1] amino acid balance studies, for assessment of protein and amino acid requirements. However, a detailed examination of IAAO studies shows both a lack of concern for homeostatic regulation of amino acid oxidation and  major flaws in their design and analytical interpretation, which seriously constrain their ability to provide reliable values. New ideas and a much more critical approach to existing work is needed if real progress is to be made in the area.

The Relationship Between Vitamin D Intake and Serum 25-hydroxyvitamin D in Young Children: A Meta-Regression to Inform WHO/FAO Vitamin D Intake Recommendations.

BACKGROUND: This work was commissioned by the World Health Organization and Food and Agriculture Organization to inform their update on the vitamin D requirements for children aged <4 y. OBJECTIVES: The objective of this work was to undertake multilevel and multivariable dose-response modeling of serum 25-hydroxyvitamin D (25OHD) to total vitamin D intake in children aged <4 y with the goal of deriving updated vitamin D requirements for young children. METHODS: Systematically identified randomized controlled trials among healthy children from 2 wk up to 3.9 y of age provided with daily vitamin D supplements or vitamin D-fortified foods were included. Linear and nonlinear random effects multilevel meta-regression models with and without covariates were fitted and compared. Interindividual variability was included by simulating the individual serum 25OHD responses. The percentage of individuals reaching set minimal and maximal serum 25OHD thresholds was calculated and used to derive vitamin D requirements. RESULTS: A total of 31 trials with 186 data points from North America, Europe, Asia, and Australasia/Oceania, with latitudes ranging from 61°N to 38°S, and with participants of likely mostly light or medium skin pigmentation, were included. In 29 studies the children received vitamin D supplements and in 2 studies the children received vitamin D-fortified milk with or without supplements. The dose-response relationship between vitamin D intake and serum 25OHD was best fitted with the unadjusted quadratic model. Adding additional covariates, such as age, did not significantly improve the model. At a vitamin D intake of 10 µg/d, 97.3% of the individuals were predicted to achieve a minimal serum 25OHD threshold of 28 nmol/L. At a vitamin D intake of 35 µg/d, 1.4% of the individuals predicted to reach a maximal serum 25OHD threshold of 200 nmol/L. CONCLUSIONS: In conclusion, this paper details the methodological steps taken to derive vitamin D requirements in children aged <4 y, including the addition of an interindividual variability component.