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

Associations of Maternal Nutritional Status and Supplementation with Fetal, Newborn, and Infant Outcomes in Low-Income and Middle-Income Settings: An Overview of Reviews

BACKGROUND/OBJECTIVES

Despite advances in maternal nutritional knowledge, the effect of maternal diet, micronutrient status and undernutrition, and the effect of maternal supplementation on fetal, neonatal and infant outcomes still have gaps in the literature. This overview of reviews is intended to assess the available information on these issues and identify the main maternal nutritional factors associated with offspring outcomes in low- and middle-income countries as possible targets for public health interventions.

METHODS

The literature search was performed in Medline (PubMed) and Cochrane Library datasets in June 2024. Pre-specified outcomes in offspring were pooled using standard meta-analytical methods.

RESULTS

We found consistent evidence on the impact of maternal undernutrition indicated by low body mass index (BMI), mid-upper arm circumference (MUAC), and stature, but not of individual micronutrient status, on intrauterine-growth retardation, preterm birth, low birth weight, and small for gestational age, with research showing a possible effect of maternal undernutrition in later child nutritional status. Studies on micronutrient supplementation showed possible beneficial effects of iron, vitamin D, and multiple micronutrients on birthweight and/or decreasing small for gestational age, as well as a possible effect of calcium on preterm birth reduction. Interventions showing more consistent beneficial outcomes were balanced protein-energy and lipid base supplements, which demonstrated improved weight in newborns from supplemented mothers and a decreased risk of adverse neonatal outcomes.

CONCLUSIONS

Further research is needed to identify the benefits and risks of maternal individual micronutrient supplementation on neonatal and further child outcomes.

Evaluation of dietary composition between hemoglobin categories, total body iron content and adherence to multi-micronutrients in preschooler residents of the highlands of Puno, Peru

BACKGROUND

The anemia prevalence is higher in highlands populations. It is assumed that iron deficiency anemia (IDA) in children is mainly due to low dietary intake. However, other suggest that high prevalence of anemia is due to an inappropriate hemoglobin (Hb) adjustment for altitude.

MATERIALS AND METHODS

Cross-sectional study conducted in 338 preschoolers (PSC) from Puno-Peru. Hb was measured in whole blood, and ferritin, Soluble transferrin receptor, and Interleukin 6 in serum.The dietary iron intake was assessed by 24-h dietary recall, using NutriCap Software. Hb concentration was assessed as adjusted or unadjusted for altitude.

RESULTS

With unadjusted Hb, the anemia prevalence was 4.7%, whereas after Hb correction, the prevalence raised-up to 65.6% (p < 0.001). Reciprocally, erythrocytosis proportion decreased from 20.35 to 0.30% (p < 0.001). Total Body Iron (TBI) showed that 7.44% had ID and 0.32% had IDA. PSC with normal unadjusted Hb levels have more protein and micronutrients intake than anemic ones. PSC with erythrocytosis consumed less fat, and more niacin and ascorbic acid than anemics. Total iron intake was lower in anemic than the other groups, but without statistical significance due to the standard deviation of the data in a small number of anemic PSC (n = 16). TBI, unadjusted Hb, and adjusted Hb were not different between groups consuming or not multimicronutrients.

CONCLUSIONS

The consumption of iron and iron status in children who live at high altitude is adequate, and that anemia could be due to other micronutrient deficiencies and/or that the adjustment of Hb by altitude is inappropriate.

Multiple Indicators of Undernutrition, Infection, and Inflammation in Lactating Women Are Associated with Maternal Iron Status and Infant Anthropometry in Panama: The MINDI Cohort

Maternal infections, nutrient deficiencies, and inflammation (MINDI) co-exist in lactating indigenous women in Panama, but their impact on maternal iron status and infant growth is unknown. For this secondary analysis of cross-sectional data of lactating mothers from our MINDI cohort, we investigated associations of MINDI variables with maternal anemia, elevated serum transferrin receptor (sTfR), low serum iron, hepcidin, ferritin, and infant weight-for-age (WAZ), length-for-age (LAZ), and head-circumference-for-age (HCAZ) Z-scores in 99 mother-infant dyads. A bootstrapping resampling procedure preselected covariates for inclusion in multivariable regressions models from chronic maternal infections and nutritional status [folate, vitamins A, D, retinol-binding protein (RBP), insulin-growth factor-1 (IGF-1)] and inflammation [C-reactive protein (CRP), cytokines, platelet indices] indicators. Anemia was prevalent (53.5%) but underestimated due to widespread low plasma volume (<2.2 L, 79.9%) and was associated with indicators of malnutrition [lower IGF-1, body mass index (BMI), vitamin D, and intake of green/leafy vegetables], but not inflammation. Higher CRP was associated with lower serum iron, and higher hepcidin and ferritin, whereas maternal platelets were associated with lower HCAZ (β = −0.22), WAZ (β = −0.17), and LAZ (β = −0.17). Higher LAZ was also associated with maternal serum vitamin D (β = 0.23), whereas maternal iron supplementation lowered LAZ (β = −0.22). Assessment of iron status in this MINDI cohort is complex and supplementation strategies must consider consequences for both the mother and the infant.

Oral iron supplementation in patients with chronic kidney disease: Can it be harmful to the gut microbiota?

Patients with chronic kidney disease (CKD) have several pathophysiological alterations, including anemia, one of the first changes in CKD patients. More recently, researchers have observed that the intestinal microbiota alterations are also another complication in these patients. The most common treatment for anemia is oral (mainly ferrous sulfate) or intravenous iron supplementation. Despite being a necessary treatment, recent studies have reported that supplementation with oral iron may increase its availability in the intestine, leading to disturbance in the gut microbiota and also to oxidative stress in the enterocytes, which may change the permeability and the microbiota profile. Although it is a therapy routinely used in patients with CKD, supplementation with oral iron on the gut microbiota has been rarely studied in these patients. Thus, this review will discuss the relationship between iron and the gut microbiota and the possible effects of oral iron supplementation on gut microbiota in patients with CKD.