Zinc and infant nutrition

Revised D-A-CH-reference values for the intake of zinc

BACKGROUND

The Nutrition Societies of Germany, Austria and Switzerland as the joint editors of the 'D-A-CH reference values for nutrient intake' have revised the reference values for zinc in July 2019.

METHODS

For infants aged 0 to under 4 months, an estimated value was set based on the zinc intake via breast feeding. For all other age groups, the reference values were calculated using the factorial method considering endogenous zinc losses via intestinal losses, urine, faeces, skin and sweat, semen in men and the additional zinc requirements to build up body weight in children and adolescents as well as in pregnant women. Due to the strong influence of phytate intake on zinc absorption, the recommendations for the intake of zinc for adults are derived depending on low (0.5 mmol/day, corresponding to 330 mg/day), moderate (1.0 mmol/day, corresponding to 660 mg/day) and high (1.5 mmol/day, corresponding to 990 mg/day) phytate intake. The reference values for lactating women take into account the zinc loss via breast milk.

RESULTS AND CONCLUSION

For adults, pregnant and lactating women, the recommended intake values for zinc range from 7 mg/day to 16 mg/day, depending on sex and dietary phytate intake.

Nutritional Gaps and Supplementation in the First 1000 Days

Optimized nutrition during the first 1000 days (from conception through the 2nd birthday) is critical for healthy development and a healthy life for the newborn. Pregnancy and the postpartum period are accompanied by physiological changes, increased energy needs, and changing requirements in the nutrients critical for optimal growth and development. Infants and toddlers also experience physiological changes and have specific nutritional needs. Food and nutrition experts can provide women of childbearing age with adequate dietary advice to optimize nutrition, as well as guidance on selecting appropriate dietary supplements. Considering the approaching 2020-2025 Dietary Guidelines for Americans (DGA) will be making specific recommendations for children, it is important to provide accurate scientific information to support health influencers in the field of nutrition. The purpose of this review is to summarize the nutrition and supplementation literature for the first 1000 days; to highlight nutritional and knowledge gaps; and to educate nutrition influencers to provide thoughtful guidance to mothers and families. Optimal nutrition during pregnancy through early childhood is critical for supporting a healthy life. Nutrition influencers, such as dietitians, obstetricians/gynecologists, and other relevant health professionals, should continue guiding supplement and food intake and work closely with expectant families and nutrition gatekeepers.

Zinc fortification as a tool for improving sprout hygienic and nutritional quality: a factorial design approach

BACKGROUND

Sprouting is known to improve cereal and pulse nutritional properties. However, several outbreaks of illness have been reported after raw sprout consumption. This research aimed to improve wheat sprout hygienic properties through the use of zinc diacetate. Sprouting conditions (sprouting temperature, soaking time and zinc diacetate solution concentration) were optimized to decrease total plate count, coliforms, and molds and yeasts using a factorial design approach and a desirability function.

RESULTS

Based on the responses, the effects of variables were calculated and the interactions between them were determined. Optimal conditions were defined as follows: sprouting temperature 18 °C, soaking time 0.66 h and zinc diacetate concentration 400 mg L^-1 . These conditions led to the elimination of coliforms and a decrease in total flora count by 2 log. Interestingly, zinc sprouting increased the zinc content of sprouts and improved their nutritional properties.

CONCLUSION

Results showed that the use of zinc solution is a useful tool to improve sprout hygienic and nutritional properties. © 2019 Society of Chemical Industry.

Longitudinal Changes of Mineral Concentrations in Preterm and Term Human Milk from Lactating Swiss Women

An adequate mineral supply to preterm infants is essential for normal growth and development. This study aimed to compare the mineral contents of human milk (HM) from healthy mothers of preterm (28-32 weeks) and full term (>37 weeks) infants. Samples were collected weekly for eight weeks for the term group (n = 34) and, biweekly up to 16 weeks for the preterm group (n = 27). Iron, zinc, selenium, copper, iodine, calcium, magnesium, phosphorus, potassium, and sodium were quantitatively analyzed by Inductively Coupled Plasma-Mass Spectrometry. The mineral contents of both HM showed parallel compositional changes over the period of lactation, with occasional significant differences when compared at the same postpartum age. However, when the comparisons were performed at an equivalent postmenstrual age, preterm HM contained less zinc and copper from week 39 to 48 (p < 0.002) and less selenium from week 39 to 44 (p < 0.002) than term HM. This translates into ranges of differences (min-max) of 53% to 78%, 30% to 72%, and 11% to 33% lower for zinc, copper, and selenium, respectively. These data provide comprehensive information on the temporal changes of ten minerals in preterm HM and may help to increase the accuracy of the mineral fortification of milk for preterm consumption.

Dysmaturation of Premature Brain: Importance, Cellular Mechanisms, and Potential Interventions

Prematurity, especially preterm birth (less than 32 weeks' gestation), is common and associated with high rates of both survival and neurodevelopmental disability, especially apparent in cognitive spheres. The neuropathological substrate of this disability is now recognized to be related to a variety of dysmaturational disturbances of the brain. These disturbances follow initial brain injury, particularly cerebral white matter injury, and involve many of the extraordinary array of developmental events active in cerebral white and gray matter structures during the premature period. This review delineates these developmental events and the dysmaturational disturbances that occur in premature infants. The cellular mechanisms involved in the genesis of the dysmaturation are emphasized, with particular focus on the preoligodendrocyte. A central role for the diffusely distributed activated microglia and reactive astrocytes in the dysmaturation is now apparent. As these dysmaturational cellular mechanisms appear to occur over a relatively long time window, interventions to prevent or ameliorate the dysmaturation, that is, neurorestorative interventions, seem possible. Such interventions include pharmacologic agents, especially erythropoietin, and particular attention has also been paid to such nutritional factors as quality and source of milk, breastfeeding, polyunsaturated fatty acids, iron, and zinc. Recent studies also suggest a potent role for interventions directed at various experiential factors in the neonatal period and infancy, i.e., provision of optimal auditory and visual exposures, minimization of pain and stress, and a variety of other means of environmental behavioral enrichment, in enhancing brain development.

Impact of delivery mode on the levels of essential trace elements in breast milk

Aim: This study investigated whether the parturition mode (vaginal or cesarean [C-] section) affects breast milk concentrations of four essential trace elements (iron, copper, zinc, and manganese).Methods: Women giving birth at seven hospitals in seven different regions of China were enrolled in the study. Each participant provided breast milk, collected on postpartum day 3-5, for determination of iron, copper, zinc, and manganese concentrations. Breast milk concentrations of the subject trace elements were compared between women giving birth vaginally or via C-section.Results: Of the 1243 women enrolled in the study, 617 (49.6%) gave birth via the vaginal route and 626 (50.4%) delivered via C-section. The mean milk concentrations of iron, copper, zinc, and manganese in the milk of women delivering via the vaginal route were higher than those in the milk of women delivering via C-section; only the copper concentration differences were statistically significant, after adjusting for confounding factors (p = .023).Conclusion: Delivery mode impacts breast milk concentrations of essential trace elements, with vaginal delivery being associated with higher essential trace element concentrations than C-sections.

Zinc Nutritional Status in Patients with Cystic Fibrosis

BACKGROUND

Zinc is an essential nutrient for all forms of life and its deficiency affects the normal growth and development of human beings.

OBJECTIVE

The main aim was to investigate zinc nutritional status by serum zinc concentration (SZC) and dietary zinc intake and their association in cystic fibrosis (CF) patients.

METHODS

A cross-sectional study was conducted in CF patients. Anthropometric measurements and respiratory and pancreatic tests were conducted. Hypozincemia was determined by SZC while using atomic absorption spectrophotometry and dietary zinc deficiency by prospective 72-h dietary surveys.

RESULTS

Mean SZC (87.2 ± 16.7 μg/dL) and dietary zinc intake (97 ± 26.9% Dietary Reference Intake) were normal. Three of 17 patients with CF (17.6%) had hypozincemia and four (23.5%) had a dietary zinc deficiency. No patient with dietary zinc deficiency had hypozincemia. A positive and significant association was observed between SZC and Z-score of BMI-for-age (p = 0.048) and weight-for-height (p = 0.012) and between dietary zinc intake and energy intake (EI, p = 0.036) and Z-score of weight-for-high (p = 0.029).

CONCLUSION

SZC was associated with the nutritional status, expressed as BMI (Body Mass Index) and weight-for-height Z score, and dietary zinc intake with EI and weight-for-height Z-score. No patient with hypozincemia had dietary zinc deficiency. This situation should alert us to a marginal zinc deficiency and it may explain why there were no overlapping cases between the two groups. We suggest that probably 41% of the cases in this study would be at elevated risk of zinc deficiency and a zinc supplementation may be considered.

Assessment of coupled Zn concentration and natural stable isotope analyses of urine as a novel probe of Zn status

Heavier Zn isotope compositions in urine compared to blood serum and an accompanying isotope-concentration trend likely reflects Zn processing in the kidneys in response to bodily Zn requirements.

Prevalence and outcome of stress hyperglycaemia among severely malnourished children admitted to Mulago referral and teaching hospital in Kampala, Uganda

Background

Stress hyperglycaemia is a transient increase in blood glucose level during stressful events and is common in critically ill children. Several studies have demonstrated increased risk of mortality in these children. There is paucity of information on this subject in sub Saharan Africa.The aim of this study was to describe the prevalence, outcome and factors associated with stress hyperglycaemia among children with severe acute malnutrition (SAM) admitted to the Mwanamugimu nutrition unit of Mulago hospital in Uganda.

Methods

This study was conducted from August 2015 to March 2016 at the Mwanamugimu nutrition unit of Mulago hospital among severely malnourished children aged 1 to 60 months. Random blood sugar levels were measured. Stress hyperglycaemia was considered as a random blood sugar > 150 mg/dl. The final outcome was ascertained at death or discharge. Statistical analysis was done using the Chi square test and logistic regression.

Results

Two hundred and thirty-five children were enrolled of whom 50% were girls. The median age was 5.1 months (range 1-60 months). Stress hyperglycaemia was present in 16.6% of the 235 participants. Several factors were significantly associated with stress hyperglycaemia at bivariate analysis; but on logistic regression, only presence of oral sores was associated with stress hyperglycaemia: (Odds ratio 2.61; 95% CI 1.02-6.65).Mortality was higher among children with stress hyperglycaemia (56.4%) compared to (12.8%) in the non-hyperglycaemic group: OR 8.75; 95% CI 4.09-18.70).

Conclusion

The prevalence of stress hyperglycaemia was 16.6% and was associated with high mortality. It is important to monitor blood glucose levels of severely malnourished children. Hitherto, the main concern among severely malnourished children has been hypoglycaemia. Innovative ways of preventing and managing stress hyperglycaemia among these children are urgently needed.

Zinc Content in Breast Milk and Its Association with Maternal Diet

BACKGROUND

Zinc is an indispensable element, being involved in many biological processes. Correspondingly, insufficient zinc intake in early youth can detrimentally affect the function of a growing body. The aim of this study was to determine zinc content in breast milk among lactating women in Latvia and factors (maternal diet; mother's and baby's characteristics; breastfeeding pattern) affecting it.

METHODS

In total, 62 mature milk (at least one month postpartum) samples were collected and pooled within 24 h. Zinc content (mg 100 mL-1) was determined using inductively coupled plasma mass spectrometry (ICP-MS; Agilent 7700×, Agilent Technologies, Tokyo, Japan).

RESULTS

Zinc content in mature breast milk ranged from 0.01 to 0.34 mg 100 mL-1 with a median (interquartile range) content of 0.10 (0.05⁻0.15) mg 100 mL-1. Time postpartum was a significant negative predictor for zinc content in breast milk (r = -0.500; p = 0.000). Median maternal zinc intake was 10.70 (7.24⁻15.27) mg. Yet, zinc content in breast milk was unaffected by maternal dietary zinc intake (r = 0.155; p = 0.221).

CONCLUSIONS

Maternal dietary zinc intake was nearly the recommended intake for lactating women (11 mg), but due to low zinc content in breast milk, babies in Latvia might not receive sufficient zinc intake. Future research should aim for the assessment of zinc status by evaluating plasma or serum levels of both mothers and babies.

Epigenetics and Malaria Susceptibility/Protection: A Missing Piece of the Puzzle

A better understanding of stable changes in regulation of gene expression that result from epigenetic events is of great relevance in the development of strategies to prevent and treat infectious diseases. Histone modification and DNA methylation are key epigenetic mechanisms that can be regarded as marks, which ensure an accurate transmission of the chromatin states and gene expression profiles over generations of cells. There is an increasing list of these modifications, and the complexity of their action is just beginning to be understood. It is clear that the epigenetic landscape plays a fundamental role in most biological processes that involve the manipulation and expression of DNA. Although the molecular mechanism of gene regulation is relatively well understood, the hierarchical order of events and dependencies that lead to protection against infection remain largely unknown. In this review, we propose that host epigenetics is an essential, though relatively under studied, factor in the protection or susceptibility to malaria.

A review of select minerals influencing the haematopoietic process

Micronutrients are indispensable for adequate metabolism, such as biochemical function and cell production. The production of blood cells is named haematopoiesis and this process is highly consuming due to the rapid turnover of the haematopoietic system and consequent demand for nutrients. It is well established that micronutrients are relevant to blood cell production, although some of the mechanisms of how micronutrients modulate haematopoiesis remain unknown. The aim of the present review is to summarise the effect of Fe, Mn, Ca, Mg, Na, K, Co, iodine, P, Se, Cu, Li and Zn on haematopoiesis. This review deals specifically with the physiological requirements of selected micronutrients to haematopoiesis, showing various studies related to the physiological requirements, deficiency or excess of these minerals on haematopoiesis. The literature selected includes studies in animal models and human subjects. In circumstances where these minerals have not been studied for a given condition, no information was used. All the selected minerals have an important role in haematopoiesis by influencing the quality and quantity of blood cell production. In addition, it is highly recommended that the established nutrition recommendations for these minerals be followed, because cases of excess or deficient mineral intake can affect the haematopoiesis process.

Zinc, Carnosine, and Neurodegenerative Diseases

Zinc (Zn) is abundantly present in the brain, and accumulates in the synaptic vesicles. Synaptic Zn is released with neuronal excitation, and plays essential roles in learning and memory. Increasing evidence suggests that the disruption of Zn homeostasis is involved in various neurodegenerative diseases including Alzheimer's disease, a vascular type of dementia, and prion diseases. Our and other numerous studies suggest that carnosine (β-alanyl histidine) is protective against these neurodegenerative diseases. Carnosine is an endogenous dipeptide abundantly present in the skeletal muscles and in the brain, and has numerous beneficial effects such as antioxidant, metal chelating, anti-crosslinking, and anti-glycation activities. The complex of carnosine and Zn, termed polaprezinc, is widely used for Zn supplementation therapy and for the treatment of ulcers. Here, we review the link between Zn and these neurodegenerative diseases, and focus on the neuroprotective effects of carnosine. We also discuss the carnosine level in various foodstuffs and beneficial effects of dietary supplementation of carnosine.