Comparison of test performance of two commonly used multiplex assays to measure micronutrient and inflammatory markers in serum: results from a survey among pregnant women in South Africa.

The combined sandwich-ELISA (s-ELISA; VitMin Lab, Germany) and the Quansys Q-Plex™ Human Micronutrient Array (7-Plex) are multiplex serum assays that are used to assess population micronutrient status in low-income countries. We aimed to compare the agreement of five analytes, α-1-acid glycoprotein (AGP), C-reactive protein (CRP), ferritin, retinol-binding protein 4 (RBP4) and soluble transferrin receptor (sTfR) as measured by the 7-Plex and the s-ELISA. Serum samples were collected between March 2016 and December 2017. Pregnant women (n 249) were recruited at primary healthcare clinics in Johannesburg, and serum samples were collected between March 2016 and December 2017. Agreement between continuous measurements was assessed by Bland-Altman plots and concordance measures. Agreement in classifications of deficiency or inflammation was assessed by Cohen's kappa. Strong correlations (r > 0·80) were observed between the 7-Plex and s-ELISA for CRP and ferritin. Except for CRP, the 7-Plex assay gave consistently higher measurements than the s-ELISA. With the exception of CRP (Lin's ρ = 0·92), there was poor agreement between the two assays, with Lin's ρ < 0·90. Discrepancies of test results difference between methods increased as the serum concentrations rose. Cohen's kappa for all the five analytes was < 0·81 and ranged from slight agreement (vitamin A deficiency) to substantial (inflammation and Fe deficiency) agreement. The 7-Plex 1.0 is a research and or surveillance tool with potential for use in low-resource laboratories but cannot be used interchangeably with the s-ELISA. Further optimising and validation is required to establish its interchangeability with other validated methods.

Iron status in Swiss adolescents with paediatric major depressive disorder and healthy controls: a matched case-control study.

PURPOSE: Depression is associated with low-grade systemic inflammation and impaired intestinal function, both of which may reduce dietary iron absorption. Low iron status has been associated with depression in adults and adolescents. In Swiss adolescents, we determined the associations between paediatric major depressive disorder (pMDD), inflammation, intestinal permeability and iron status. METHODS: This is a matched case-control study in 95 adolescents with diagnosed pMDD and 95 healthy controls aged 13-17 years. We assessed depression severity using the Children's Depression Rating Scale-Revised. We measured iron status (serum ferritin (SF) and soluble transferrin receptor (sTfR)), inflammation (C-reactive protein (CRP) and alpha-1-acid-glycoprotein (AGP)), and intestinal permeability (intestinal fatty acid binding protein (I-FABP)). We assessed history of ID diagnosis and treatment with a self-reported questionnaire. RESULTS: SF concentrations did not differ between adolescents with pMDD (median (IQR) SF: 31.2 (20.2, 57.0) µg/L) and controls (32.5 (22.6, 48.3) µg/L, p = 0.4). sTfR was lower among cases than controls (4.50 (4.00, 5.50) mg/L vs 5.20 (4.75, 6.10) mg/L, p < 0.001). CRP, AGP and I-FABP were higher among cases than controls (CRP: 0.16 (0.03, 0.43) mg/L vs 0.04 (0.02, 0.30) mg/L, p = 0.003; AGP: 0.57 (0.44, 0.70) g/L vs 0.52 (0.41, 0.67) g/L, p = 0.024); I-FABP: 307 (17, 515) pg/mL vs 232 (163, 357) pg/mL, p = 0.047). Of cases, 44% reported having a history of ID diagnosis compared to 26% among controls (p = 0.020). Finally, 28% of cases had iron treatment at/close to study inclusion compared to 14% among controls. CONCLUSION: Cases had significantly higher systemic inflammation and intestinal permeability than controls but did not have lower iron status. Whether this is related to the higher rate of ID diagnosis and iron treatment in adolescents with depression is uncertain.

Iron and n-3 fatty acid depletion, alone and in combination, during early development provoke neurochemical changes, anhedonia, anxiety and social dysfunction in rats.

Objectives: Both iron and omega-3 (n-3) fatty acids (FA) play important roles in the development and functioning of the brain. We investigated the effects of n-3 FA and iron deficiencies, alone and in combination, during early development on behaviour and brain monoamines in rats. Methods: Using a 2-factorial design, female Wistar rats were randomly allocated to one of four diet groups: Control, n-3 FA deficient (n-3 FAD), iron deficient (ID), or n-3 FAD + ID. Females received these diets throughout mating, pregnancy and lactation. Offspring (n = 24/group; male:female = 1:1) continued on the same diet until post-natal day 42-45, and underwent a sucrose preference test (SPT), novel object recognition test, elevated plus maze (EPM) and social interaction test (SIT). Results: ID offspring consumed less sucrose in the SPT and spent more time in closed arms and less time in open arms of the EPM than non-ID offspring. In female offspring only, ID and n-3 FAD reduced time approaching and together in the SIT, with an additive effect of ID and n-3 FAD for even less time approaching and spent together in the n-3 FAD + ID group compared to controls. ID offspring had higher striatal dopamine and norepinephrine and lower frontal cortex dopamine concentrations. N-3 FAD and ID affected frontal cortex serotonin concentrations in a sex-specific manner. Conclusions: Our results suggest that ID and n-3 FAD during early development provoke anhedonia, anxiety and social dysfunction in rats, with potential additive and attenuating effects when combined. These effects may in part be attributed to disturbances in brain neurochemistry and may be sex-specific.

Associations of HIV and iron status with gut microbiota composition, gut inflammation and gut integrity in South African school-age children: a two-way factorial case-control study.

BACKGROUND: Human immunodeficiency virus (HIV) and iron deficiency (ID) affect many African children. Both HIV and iron status interact with gut microbiota composition and related biomarkers. The study's aim was to determine the associations of HIV and iron status with gut microbiota composition, gut inflammation and gut integrity in South African school-age children. METHODS: In this two-way factorial case-control study, 8- to 13-year-old children were enrolled into four groups based on their HIV and iron status: (1) With HIV (HIV+) and ID (n = 43), (2) HIV+ and iron-sufficient nonanaemic (n = 41), (3) without HIV (HIV-) and ID (n = 44) and (4) HIV- and iron-sufficient nonanaemic (n = 38). HIV+ children were virally suppressed (<50 HIV RNA copies/ml) on antiretroviral therapy (ART). Microbial composition of faecal samples (16S rRNA sequencing) and markers of gut inflammation (faecal calprotectin) and gut integrity (plasma intestinal fatty acid-binding protein [I-FABP]) were assessed. RESULTS: Faecal calprotectin was higher in ID versus iron-sufficient nonanaemic children (p = 0.007). I-FABP did not significantly differ by HIV or iron status. ART-treated HIV (redundancy analysis [RDA] R2 = 0.009, p = 0.029) and age (RDA R2 = 0.013 p = 0.004) explained the variance in the gut microbiota across the four groups. Probabilistic models showed that the relative abundance of the butyrate-producing genera Anaerostipes and Anaerotruncus was lower in ID versus iron-sufficient children. Fusicatenibacter was lower in HIV+ and in ID children versus their respective counterparts. The prevalence of the inflammation-associated genus Megamonas was 42% higher in children with both HIV and ID versus HIV- and iron-sufficient nonanaemic counterparts. CONCLUSIONS: In our sample of 8- to 13-year-old virally suppressed HIV+ and HIV- children with or without ID, ID was associated with increased gut inflammation and changes in the relative abundance of specific microbiota. Moreover, in HIV+ children, ID had a cumulative effect that further shifted the gut microbiota to an unfavourable composition.

The effect of oral iron supplementation on the gut microbiota, gut inflammation, and iron status in iron-depleted South African school-age children with virally suppressed HIV and without HIV.

PURPOSE: Both HIV and oral iron interventions may alter gut microbiota composition and increase gut inflammation. We determined the effect of oral iron supplementation on gut microbiota composition, gut inflammation, and iron status in iron-depleted South Africa school-aged children living with HIV (HIV+) but virally suppressed on antiretroviral therapy and children without HIV (HIV-ve). METHODS: In this before-after intervention study with case-control comparisons, we provided 55 mg elemental iron from ferrous sulphate, once daily for 3 months, to 33 virally suppressed (< 50 HIV RNA copies/mL) HIV+ and 31 HIV-ve children. At baseline and endpoint, we assessed microbial composition of faecal samples (16S rRNA sequencing), and markers of gut inflammation (faecal calprotectin), anaemia (haemoglobin) and iron status (plasma ferritin, soluble transferrin receptor). This study was nested within a larger trial registered at clinicaltrials.gov as NCT03572010. RESULTS: HIV+ (11.3y SD ± 1.8, 46% male) and HIV-ve (11.1y SD ± 1.7, 52% male) groups did not significantly differ in age or sex ratio. Following iron supplementation, improvements were observed in haemoglobin (HIV+ : 118 to 124 g/L, P = 0.003; HIV-ve: 120 to 124 g/L, P = 0.003), plasma ferritin (HIV+ : 15 to 34 µg/L, P < 0.001; HIV-ve: 18 to 37 µg/L, P < 0.001), and soluble transferrin receptor (HIV+ : 7.1 to 5.9 mg/L, P < 0.001; HIV-ve: 6.6 to 5.7 mg/L, P < 0.001), with no significant change in the relative abundance of any genera, alpha diversity of the gut microbiota (HIV+ : P = 0.37; HIV-ve: P = 0.77), or faecal calprotectin (HIV+ : P = 0.42; HIV-ve: P = 0.80). CONCLUSION: Our findings suggest that oral iron supplementation can significantly improve haemoglobin and iron status without increasing pathogenic gut microbial taxa or gut inflammation in iron-depleted virally suppressed HIV+ and HIV-ve school-age children.

The effect of a natural polyphenol supplement on iron absorption in adults with hereditary hemochromatosis.

OBJECTIVES: We developed a natural polyphenol supplement that strongly chelates iron in vitro and assessed its effect on non-heme iron absorption in patients with hereditary hemochromatosis (HH). METHODS: We performed in vitro iron digestion experiments to determine iron precipitation by 12 polyphenol-rich dietary sources, and formulated a polyphenol supplement (PPS) containing black tea powder, cocoa powder and grape juice extract. In a multi-center, single-blind, placebo-controlled cross-over study, we assessed the effect of the PPS on iron absorption from an extrinsically labelled test meal and test drink in patients (n = 14) with HH homozygous for the p.C282Y variant in the HFE gene. We measured fractional iron absorption (FIA) as stable iron isotope incorporation into erythrocytes. RESULTS: Black tea powder, cocoa powder and grape juice extract most effectively precipitated iron in vitro. A PPS mixture of these three extracts precipitated ~ 80% of iron when 2 g was added to a 500 g iron solution containing 20 µg Fe/g. In the iron absorption study, the PPS reduced FIA by ~ 40%: FIA from the meal consumed with the PPS was lower (3.01% (1.60, 5.64)) than with placebo (5.21% (3.92, 6.92)) (p = 0.026)), and FIA from the test drink with the PPS was lower (10.3% (7.29 14.6)) than with placebo (16.9% (12.8 22.2)) (p = 0.002). CONCLUSION: Our results indicate that when taken with meals, this natural PPS can decrease dietary iron absorption, and might thereby reduce body iron accumulation and the frequency of phlebotomy in patients with HH. TRIAL REGISTRY: clinicaltrials.gov (registration date: 9.6.2019, NCT03990181).

Moving Complementary Feeding Forward: Report on a Workshop of the Federation of International Societies for Pediatric Gastroenterology, Hepatology and Nutrition (FISPGHAN) and the World Health Organization Regional Office for Europe.

The WHO Regional Office for Europe and the Federation of International Societies for Pediatric Gastroenterology, Hepatology, and Nutrition held a joint workshop, "Moving Complementary Feeding Forward" at the sixth World Congress Pediatric Gastroenterology, Hepatology, and Nutrition in 2021. Here we summarize workshop presentations and discussions. The workshop covered health implications of complementary feeding (CF) including allergies, challenges to meet dietary needs during the CF period, quality of commercial complementary foods (CFD) and respective marketing practices, national CF guidelines in Europe, a nutrient profiling system for CFD, and global policy perspectives on the standards and regulation of marketing for CFD. Adequate CF practices are of critical importance for short and long-term child health, prevention of nutrient deficiencies, normal growth and development, and reducing the risk of allergies. The workshop identified the need to improve feeding practices, harmonize evidence-based information and develop guidance jointly with various stakeholders, improve the composition and marketing practices of commercial CFD and their transparent labeling based on nutrient profiling. Renewed efforts for collaboration between scientists, public health experts, pediatric associations, national governments, and the WHO are necessary for advancing progress.

Iodine status of pregnant women living in urban Johannesburg, South Africa.

Adequate intake of iodine is important during pregnancy because of its essential role in foetal growth and neurodevelopment. Data on iodine status of South African pregnant women are scarce, and the salt reduction policy implemented in 2016 may decrease iodine intake of South Africans. This cross-sectional study assessed the iodine status of pregnant women residing in urban Johannesburg, South Africa. A total of 250 pregnant women were enrolled into the 'Nutrition during Pregnancy and Early Development' (NuPED) study and 312 pregnant women into the 'Assessment of dried blood spot thyroglobulin in pregnant women to redefine the range of median urinary iodine concentration that indicates adequate iodine intake, South Africa' (STRIPE-SA) study and were included in this analysis. Urinary iodine concentration (UIC) was analysed in a spot urine sample. Thyroglobulin (Tg) was measured in serum, and thyroid-stimulating hormone (TSH) and total thyroxine (tT4) were measured in dried blood spots. The median [interquartile range (IQR)] UIC of pregnant women was 144 (84-234) µg/L. Women in the first (n = 99), second (n = 262) and third (n = 174) trimester had a median UIC of 133 (81-316), 145 (84-236) and 156 (89-245) µg/L, respectively (p = 0.419). Median TSH, tT4 and Tg were 2.7 (2.3-3.2) mU/L, 202 (163-236) nmol/L and 9.2 (5.4-17.9) µg/L, respectively. Based on the median UIC, pregnant women residing in urban Johannesburg may be borderline iodine deficient. These findings highlight the need for ongoing monitoring of iodine status among vulnerable pregnant women, especially considering the recently introduced salt reduction policy in South Africa.

Associations of dietary diversity with anaemia and iron status among 5- to 12-year-old schoolchildren in South Africa.

OBJECTIVE: To examine the associations of dietary diversity with anaemia and iron status among primary school-aged children in South Africa. DESIGN: An analysis was conducted with pooled individual data from the baseline surveys from three previously conducted independent intervention studies. Two different dietary diversity scores (DDS) were calculated based on data from 1-day (1-d) and 3-day (3-d) dietary recall periods, respectively. Logistic regression analysis was performed to examine the associations of dietary diversity with anaemia and iron status. SETTING: KwaZulu-Natal and North West provinces, South Africa. PARTICIPANTS: Children (n 578) 5- to 12-year-old. RESULTS: A DDS ≤ 4 was associated with higher odds of being anaemic (1-d P = 0·001; 3-d P = 0·006) and being iron deficient (ID) (3-d P < 0·001). For both recall periods, consumption of 'vegetables and fruits other than vitamin A-rich' and 'animal-source foods (ASF)' was associated with lower odds of being anaemic (both P = 0·002), and 'organ meats' with lower odds of being ID (1-d P = 0·045; 3-d P < 0·001). Consumption of 'meat, chicken and fish' was associated with lower odds of being anaemic (P = 0·045), and 'vegetables and fruits other than vitamin A-rich', 'legumes, nuts and seeds' and 'ASF' with lower odds of being ID for the 3-d recall period only (P = 0·038, P = 0·020 and P = 0·003, respectively). CONCLUSION: In order to improve anaemia and iron status among primary school-aged children, dietary diversification, with emphasis on consumption of vegetables, fruits and ASF (including organ meats), should be promoted.

Determining sample size adequacy for animal model studies in nutrition research: limits and ethical challenges of ordinary power calculation procedures.

Animal models are widely used in the field of nutrition research. Scientifically and ethically sound experiments need an adequate number of experimental units. The use of 5-10 units is common, but such sample sizes can be justified for large effect sizes only. We reviewed animal model studies recently published in selected journals in the field of nutrition sciences. We performed a simulation study aimed at determining the adequate sample size for normality assessment. We then performed power calculations for a number of statistical tests commonly found in rodent model studies in nutrition research. Among the selected papers, sample sizes ranged from 6-18 units per group. None of them justified the sample size. However, such sample sizes do not allow for normality testing, thus, graphical approaches should be used. Parametric approaches result in higher statistical power when compared to their non-parametric counterparts. Repeated measures analysis should always be preferred, when possible.

Interventions to prevent iron deficiency during the first 1000 days in low-income and middle-income countries: recent advances and challenges.

PURPOSE OF REVIEW: Iron deficiency remains highly prevalent in women and young children in low-income and middle-income countries. To prevent the potentially life-long consequences of iron deficiency when occurring during early life, the WHO recommends iron supplementation of pregnant women and young children. However, increasing evidence of limited efficacy and risk of current iron intervention strategies are cause of concern. This review aims to highlight recent advances and challenges of established and novel intervention strategies for the prevention of iron deficiency during the first 1000 days in low-income and middle-income countries. RECENT FINDINGS: Recent meta-analyses and trials challenged the WHO's current recommendation to provide iron-folic acid rather than multiple micronutrient supplements during routine antenatal care. Furthermore, several studies explored optimal windows for iron supplementation, such as prior to conception. Studies are demonstrating that infectious and noninfectious inflammation is compromising the efficacy of iron interventions in vulnerable groups. Therefore, strategies addressing iron deficiency should focus on targeting infection and inflammation while simultaneously providing additional iron. Furthermore, both iron deficiency and iron supplementation may promote an unfavourable gut microbiota. Recent trials in infants indicate that the provision of a prebiotic together with iron may alleviate the adverse effects of iron on the gut microbiome and gut inflammation, and may even enhance iron absorption. SUMMARY: Recent studies highlight the need for and potential of novel intervention strategies that increase the efficacy and limit the potential harm of universal iron supplementation.

Food or nutrient pattern assessment using the principal component analysis applied to food questionnaires. Pitfalls, tips and tricks.

We considered the Blom's transformation, a statistical method aimed to normalise and standardise food intakes before principal component analysis. A simulation study was performed to evaluate the eigenvalue distribution of a correlation matrix under common conditions in food questionnaire analysis. The scree plot visual inspection and the Guttman-Kaiser (GK) criterion were compared to Horn's parallel analysis to evaluate their efficacy in food pattern identification. The scree plot results as a monotone continuous series when no food patterns are present. In this situation, about 50% of the eigenvalues assume a value higher than one, showing a first fallacy of the GK. When three food patterns are simulated a clear discontinuity appears after the third eigenvalue, showing that the scree-plot visual inspection is a suitable method to identify food patterns. Finally, according to the present work it appears that the GK generates a number of false-positive food patterns.

Associations of plasma total phospholipid fatty acid patterns with feeding practices, growth, and psychomotor development in 6-month-old South African infants.

The objective of this study was to assess plasma fatty acid (FA) patterns of 6-month-old South African infants and to determine their association with feeding practices, growth, and psychomotor development. Plasma total phospholipid FA composition (% of total FAs) of 6-month-old infants (n = 353) from a peri-urban township was analysed, and principal component and factor analysis were performed to identify plasma FA patterns. Feeding practices, anthropometric measurements, and psychomotor development scores were determined. Four major plasma phospholipid FA patterns were identified: A plant-based C18 FA, a high n-6 long-chain polyunsaturated fatty acids (LCPUFA), a C16:1 and long-chain saturated fatty acid (SFA), and a high n-3 and low n-6 LCPUFA pattern. Formula feeding was associated with higher, whereas breastfeeding was associated with lower scores for the plant-based C18 FA and C16:1 and long-chain SFA patterns. On the other hand, breastfeeding, the consumption of cow's milk, and the consumption of semisolid foods were associated with higher scores, whereas formula feeding was associated with lower scores for the high n-6 LCPUFA pattern. Breastfeeding and the consumption of semisolids were also associated with higher high n-3 and low n-6 LCPUFA pattern scores. The C16:1 and long-chain SFA and high n-3 and low n-6 LCPUFA patterns were positively associated with psychomotor development scores. In 6-month-old South African infants, we identified distinct plasma FA patterns that presumably represent the FA quality of their diet and that are associated with psychomotor development. Our results suggest that breast milk is an important source of n-6 LCPUFAs and formula-fed infants may be at risk of inadequate LCPUFA intake.

Type of dietary fat intakes in relation to all-cause and cause-specific mortality in US adults: an iso-energetic substitution analysis from the American National Health and Nutrition Examination Survey linked to the US mortality registry.

Accumulating evidence indicates that saturated fat intake is related to mortality risk increase, whereas unsaturated fat intake is associated with reduced mortality risk. The aim of the present study was to estimate the mortality risk reduction related to a dietary change from saturated fat to mono- or polyunsaturated fat intake. The American National Health and Nutrition Examination Surveys conducted between 1999 and 2010 were linked to the 2011 national US death registry resulting in an observational prospective mortality study. Proportional hazards Cox models were used to evaluate the association between saturated, monounsaturated and polyunsaturated fat with all-cause and cause-specific mortality. Substitution analysis was conducted to estimate an iso-energetic substitution of 10 % of the energy from dietary fat intake applied to the substitution of saturated fat with an equal amount of energy from monounsaturated or polyunsaturated fat. The highest tertile intakes of saturated fat resulted in an increased risk (12 %) of all-cause and specific-cause mortality, whereas the highest tertile intakes of polyunsaturated fat resulted in a reduced risk (7 %) of all-cause and specific-cause mortality when compared with the corresponding lowest tertile. Iso-energetic substitution revealed that a substitution of 10 % of energy (from total fat) from saturated fat to an equal amount of energy from monounsaturated or polyunsaturated fat resulted in a significant reduction of the mortality risk ranging from 4 to 8 %. Iso-energetic substitution of saturated fat with monounsaturated and polyunsaturated fat reduced all-cause and specific-cause mortality in US adults.

Sensitivity of fatty acid desaturation and elongation to plasma zinc concentration: a randomised controlled trial in Beninese children.

Zn status may affect fatty acid (FA) metabolism because it acts as a cofactor in FA desaturase and elongase enzymes. Zn supplementation affects the FA desaturases of Zn-deficient rats, but whether this occurs in humans is unclear. We evaluated the associations between baseline plasma Zn (PZn) concentration and plasma total phospholipid FA composition, as well as the effect of daily consumption of Zn-fortified water on FA status in Beninese children. A 20-week, double-blind randomised controlled trial was conducted in 186 school age children. The children were randomly assigned to receive a daily portion of Zn-fortified, filtered water delivering on average 2·8 mg Zn/d or non-fortified filtered water. Plasma total phospholipid FA composition was determined using capillary GLC and PZn concentrations by atomic absorption spectrometry. At baseline, PZn correlated positively with dihomo-γ-linolenic acid (DGLA, r 0·182; P=0·024) and the DGLA:linoleic acid (LA) ratio (r 0·293; P<0·000), and negatively with LA (r -0·211; P=0·009) and the arachidonic acid:DGLA ratio (r -0·170; P=0·036). With the intervention, Zn fortification increased nervonic acid (B: 0·109; 95 % CI 0·001, 0·218) in all children (n 186) and more so in children who were Zn-deficient (n 60) at baseline (B: 0·230; 95 % CI 0·023, 0·488). In conclusion, in this study, Zn-fortified filtered water prevented the reduction of nervonic acid composition in the plasma total phospholipids of children, and this effect was stronger in Zn-deficient children. Thus, Zn status may play an important role in FA desaturation and/or elongation.

Nutrition during pregnancy and early development (NuPED) in urban South Africa: a study protocol for a prospective cohort.

BACKGROUND: Adequate nutrition during pregnancy is important to ensure optimal birth outcomes, maternal health and offspring development. However, little is known about the dietary intake and nutritional status of pregnant women residing in urban South Africa. Therefore, the Nutrition during Pregnancy and Early Development (NuPED) cohort study was initiated to assess early nutrition-related exposures predictive of early childhood development in urban South Africa. METHODS: The aims of this prospective cohort study are: 1) to assess dietary intake and nutritional status of urban pregnant women in Johannesburg, South Africa, and 2) to determine associations with birth outcomes, measures of maternal health, as well as measures of offspring health and development. Pregnant women (< 18 weeks' gestation) (n = 250) are being recruited from primary healthcare clinics in Johannesburg and are followed-up at a provincial hospital. Participants' dietary intake and nutrient status (focus on micronutrients and fatty acids) are assessed at < 18, 22 and 36 weeks' gestation. Additional assessments during pregnancy include anthropometric and blood pressure measurements, obstetric ultrasound screens, and assessments of food security, maternal fatigue, prenatal depression, allergy, immune function, morbidity and gestational diabetes. At birth, maternal and neonatal health is assessed and an umbilical cord blood sample collected. Maternal and offspring health is followed-up at 6 weeks, as well as at 6, ≈7.5 and 12 months after birth. Follow-up assessments of mothers include anthropometric measures, diet history, nutrient status, blood pressure, breast milk composition, and measures of postnatal depression and fatigue. Follow-up assessments of the offspring include feeding practices, nutrient status, measures of growth, psychomotor, socio-emotional and immune development, morbidity, allergy, as well as analysis of the gut microbiome and the epigenome. DISCUSSION: Ensuring adequate nutrition during pregnancy is one of the key actions endorsed by the South African Government to promote optimal early childhood development in an effort to eradicate poverty. The results from this study may serve as a basis for the development of context-specific nutritional interventions which can improve birth outcomes and long-term quality of life of the mother and her offspring.

Chemical Composition, but Not Specific Surface Area, Affects Calcium Retention of Nanostructured Calcium Compounds in Growing Rats.

Background: Low dietary calcium intake and bioavailability may adversely affect bone health. Reducing the size of calcium compounds increases their specific surface area (SSA, expressed as m2/g) and may increase calcium dissolution and bioavailability.Objective: We investigated the influence of SSA and chemical composition on the bioavailability of calcium and compared in vitro calcium dissolution with in vivo absorption.Methods: Calcium dissolution was measured in 0.1 M phosphoric acid, whereas color and pH changes of foods were assessed as indicators for potential sensory performance. Calcium absorption, retention, and fractional retention were measured over a 5-d balance study in growing Sprague-Dawley male rats after 21 d of feeding. Femoral and vertebral bone mineral density (BMD) and extensive tissue histology were assessed at study end. The influence of SSA on calcium bioavailability was assessed by comparing the groups fed pure calcium carbonate (CaCO3) with increasing SSAs of 3, 36, and 64 m2/g (CaCO3_3, CaCO3_36 and CaCO3_64), whereas chemical composition was assessed by comparing the smallest CaCO3_64, a 50:50 wt:wt percent solution mixture of CaCO3 and hydroxyapatite_94, and pure hydroxyapatite_100.Results: In vivo, fractional calcium retention from hydroxyapatite_100 (mean ± SEM: 54.86% ± 0.95%/5 d) was significantly greater than from CaCO3_64 (49.66% ± 1.15%/5 d) (P = 0.044). Increasing SSA of the pure CaCO3 did not significantly improve calcium retention. Across all 5 groups, there were no significant differences in BMD or tissue calcification by histology. In vitro calcium dissolution did not correlate with SSA or calcium absorption. In selected food matrixes, hydroxyapatite_100 caused less color change and/or smaller pH increase than did the other calcium compounds.Conclusions: Our findings suggest that chemical composition rather than SSA is a predictor of nanostructured calcium bioavailability and that in vitro dissolution of nanostructured calcium does not predict in vivo absorption. Although its phosphorus content may limit use in some populations, nanostructured hydroxyapatite may be a promising calcium compound for food fortification.

Iodine status and associations with feeding practices and psychomotor milestone development in six-month-old South African infants.

Iodine is important for normal growth and psychomotor development. While infants below 6 months of age receive iodine from breast milk or fortified infant formula, the introduction of complementary foods poses a serious risk for deteriorating iodine status. This cross-sectional analysis assessed the iodine status of six-month-old South African infants and explored its associations with feeding practices and psychomotor milestone development. Iodine concentrations were measured in infant (n = 386) and maternal (n = 371) urine (urinary iodine concentration [UIC]), and in breast milk (n = 257 [breast milk iodine concentrations]). Feeding practices and psychomotor milestone development were assessed in all infants. The median (25th-75th percentile) UIC in infants was 345 (213-596) µg/L and was significantly lower in stunted (302 [195-504] µg/L) than non-stunted (366 [225-641] µg/L) infants. Only 6.7% of infants were deficient. Maternal UIC (128 [81-216] µg/L; rs  = 0.218, p < 0.001) and breast milk iodine concentrations (170 [110-270] µg/kg; rs  = 0.447, p < 0.0001) were associated with infant UIC. Most infants (72%) were breastfed and tended to have higher UIC than non-breastfed infants (p = 0.074). Almost all infants (95%) consumed semi-solid or solid foods, with commercial infant cereals (60%) and jarred infant foods (20%) being the most common solid foods first introduced. Infants who reported to consume commercial infant cereals ≥4 days weekly had significantly higher UIC (372 [225-637] µg/L) than those reported to consume commercial infant cereals seldom or never (308 [200-517] µg/L; p = 0.023). No associations between infant UIC and psychomotor developmental scores were observed. Our results suggest that iodine intake in the studied six-month-old infants was adequate. Iodine in breast milk and commercial infant cereals potentially contributed to this adequate intake.

Iron interventions in children from low-income and middle-income populations: benefits and risks.

PURPOSE OF REVIEW: Children from low- and middle-income countries are particularly vulnerable to develop iron deficiency and iron deficiency anaemia (IDA), which can be prevented or controlled with different iron intervention strategies. However, there is a debate on the efficacy and safety of iron interventions, especially in children from areas with a high infectious disease burden. This review provides an overview of recent trials that investigated the benefits and potential risks of iron interventions in children from low and middle-income countries. RECENT FINDINGS: Recent studies showed that intermittent iron supplementation is a promising strategy in reducing iron deficiency and IDA. Only a few studies investigated the effect of iron interventions on developmental outcomes, such as growth and cognition, and provided mixed results. An increasing number of studies reported that iron intervention increases morbidity and causes unfavourable shifts in the gut microbial composition along with increases in intestinal inflammation, particularly in children with a high infectious disease burden. SUMMARY: More studies in children from low and middle-income populations are needed that provide evidence for the beneficial effects of iron interventions on functional outcomes beyond alleviating iron deficiency and IDA, and that explore potential mechanisms underlying the negative effects of iron reported in recent trials.

Long-chain n-3 PUFA supplementation decreases physical activity during class time in iron-deficient South African school children.

Both Fe deficiency and poor n-3 fatty acid status have been associated with behavioural changes in children. In the present study, we investigated the effects of Fe and DHA+EPA supplementation, alone or in combination, on physical activity during school days and on teacher-rated behaviour in healthy Fe-deficient school children. In a 2 × 2 factorial design, children (n 98, 6-11 years) were randomly assigned to receive (1) Fe (50 mg) plus DHA (420 mg)+EPA (80 mg), (2) Fe plus placebo, (3) placebo plus DHA+EPA or (4) placebo plus placebo as oral supplements (4 d/week) for 8.5 months. Physical activity was measured during four school days at baseline and endpoint using accelerometers, and data were stratified into morning class time (08.00-10.29 hours), break time (10.30-11.00 hours) and after-break class time (11.01-12.00 hours) for analysis. Classroom behaviour was assessed at endpoint using Conners' Teacher Rating Scales. DHA+EPA supplementation decreased physical activity counts during morning class time, increased sedentary physical activity, and decreased light- and moderate-intensity physical activities. Consistently, DHA+EPA supplementation increased sedentary physical activity and decreased light-intensity physical activity during after-break class time. Even though there were no treatment effects found on teacher-rated behaviour, lower physical activity during morning class time was associated with lower levels of teacher-rated hyperactivity and oppositional behaviour at endpoint. Despite a positive association between Fe status and physical activity during break time at baseline, Fe supplementation did not affect physical activity during break time and class time. Our findings suggest that DHA+EPA supplementation may decrease physical activity levels during class time, and further indicate that accelerometry might be a useful tool to assess classroom behaviour in healthy children.