Perspective on Emerging Micronutrient Deficiencies in Latin America and the Caribbean.

The moral imperative of public health systems is to maximize the health and welfare of the population to the extent possible. Constraints often include a lack of resources, political will, popular acceptance, or an acceptable safety margin. Major agencies have established iron, iodine, and vitamin A as the principal elements for micronutrients, with folate and zinc on the second plane.

Human milk microbiome: associations with maternal diet and infant growth.

Introduction: Ingestion of human milk (HM) is identified as a significant factor associated with early infant gut microbial colonization, which has been associated with infant health and development. Maternal diet has been associated with the HM microbiome (HMM). However, a few studies have explored the associations among maternal diet, HMM, and infant growth during the first 6 months of lactation.

Human milk microbial species are associated with infant head-circumference during early and late lactation in Guatemalan mother-infant dyads.

Human milk contains abundant commensal bacteria that colonize and establish the infant's gut microbiome but the association between the milk microbiome and head circumference during infancy has not been explored. For this cross-sectional study, head-circumference-for-age-z-scores (HCAZ) of vaginally delivered breastfed infants were collected from 62 unrelated -Mayan mothers living in eight remote rural communities in the Western Highlands of Guatemala during two stages of lactation, 'early' (6-46 days postpartum, = 29) or 'late' (109-184 days postpartum, = 33). At each stage of lactation, infants were divided into HCAZ ≥ -1 SD (early: = 18; late: = 14) and HCAZ < -1 SD (early: = 11; late: = 19).

Human milk microbiome is shaped by breastfeeding practices.

There is evidence that breastfeeding practices may impact the milk microbiota diversity and differential abundance at the genera level; however, the possibility that distinct feeding practices, such as exclusive (EBF) and non-exclusive breastfeeding (non-EBF), might alter the milk microbiome at the species level has not been explored. This cross-sectional study analyzed the milk microbiome of 64 Mayan indigenous mothers from San Juan Ostuncalco in Guatemala. Two breastfeeding practices [exclusive (EBF) vs non-exclusive (non-EBF)] were analyzed at two stages of lactation [early (5-46 days post-partum) vs late (109-184 days post-partum)].

Nutrient Density as a Dimension of Dietary Quality: Findings of the Nutrient Density Approach in a Multi-Center Evaluation.

The nutrient adequacy of a diet is typically assessed by comparing estimated nutrient intakes with established average nutrient requirements; this approach does not consider total energy consumed. In this multinational survey investigation in Indonesia, Mexico, and South Africa, we explore the applications of the "critical nutrient-density approach"-which brings energy requirements into the equation-in the context of public health epidemiology. We conducted 24 h dietary recalls in convenience samples of normal-weight (BMI 18.

Infant Anthropometry and Growth Velocity Before 6 Months are Associated with Breastfeeding Practices and the Presence of Subclinical Mastitis and Maternal Intestinal Protozoa in Indigenous Communities in Guatemala.

Background: The possibility that maternal health status and breastfeeding practices contribute to growth faltering before 6 mo is underexplored.

Objectives: This longitudinal study investigated whether indicators of subclinical mastitis (SCM) and breast inflammation, maternal fecal-oral contamination, and/or breastfeeding practices were associated with infant anthropometry or growth velocity before 6 mo.

Methods: Indigenous -Mayan mother-infant dyads (= 140) were recruited.

Geographic differences in gut microbiota composition impact susceptibility to enteric infection.

Large-scale studies of human gut microbiomes have revealed broad differences in composition across geographically distinct populations. Yet, studies examining impacts of microbiome composition on various health outcomes typically focus on single populations, posing the question of whether compositional differences between populations translate into differences in susceptibility. Using germ-free mice humanized with microbiome samples from 30 donors representing three countries, we observe robust differences in susceptibility to Citrobacter rodentium, a model for enteropathogenic Escherichia coli infections, according to geographic origin.

Human Milk Microbiota in an Indigenous Population Is Associated with Maternal Factors, Stage of Lactation, and Breastfeeding Practices.

Background: Human milk contains a diverse community of bacteria that are modified by maternal factors, but whether these or other factors are similar in developing countries has not been explored. Our objective was to determine whether the milk microbiota was modified by maternal age, BMI, parity, lactation stage, subclinical mastitis (SCM), and breastfeeding practices in the first 6 mo of lactation in an indigenous population from Guatemala.

Methods: For this cross-sectional study, -Mayan indigenous mothers nursing infants aged <6 mo were recruited.

Distinct Changes Occur in the Human Breast Milk Microbiome Between Early and Established Lactation in Breastfeeding Guatemalan Mothers.

Human breast milk contains a diverse community of bacteria, but as breast milk microbiome studies have largely focused on mothers from high income countries where few women breastfeed to 6 months, the temporal changes in the breast milk microbiome that occur during later lactation stages have not been explored. For this cross-sectional study, microbiota from breast milk samples of -Mayan mothers living in eight remote rural communities in the Western Highlands of Guatemala were analyzed. All mothers delivered vaginally and breastfed their infants for 6 months.

Micronutrient supplementation of lactating Guatemalan women acutely increases infants' intake of riboflavin, thiamin, pyridoxal, and cobalamin, but not niacin, in a randomized crossover trial.

Background: Maternal supplementation during lactation could increase milk B-vitamin concentrations, but little is known about the kinetics of milk vitamin responses.

Objectives: We compared acute effects of maternal lipid-based nutrient supplement (LNS) consumption (n = 22 nutrients, 175%-212% of the RDA intake for the nutrients examined), as a single dose or at spaced intervals during 8 h, on milk concentrations and infant intake from milk of B-vitamins.

Methods: This randomized crossover trial in Quetzaltenango, Guatemala included 26 mother-infant dyads 4-6 mo postpartum who were randomly assigned to receive 3 treatments in a random order: bolus 30-g dose of LNS (Bolus); 3 × 10-g doses of LNS (Divided); and no LNS (Control), with control meals.

Vision of Research on Human Linear Growth.

The human body grows in length from conception to the maximal adult height over two decades. The shortest male population averages ∼150 cm and the tallest ∼183 cm. Nonetheless the dimensions of head and trunk are highly comparable, with the vast difference in the leg length.

Anthropometry before Day 46 and Growth Velocity before 6 Months of Guatemalan Breastfed Infants Are Associated with Subclinical Mastitis and Milk Cytokines, Minerals, and Trace Elements.

Background: Subclinical mastitis (SCM) is an inflammatory condition of the mammary gland, but its association with human milk composition and infant growth is not well described.

Objectives: We investigated whether SCM, milk cytokines, and/or estimated intakes of milk minerals and trace elements were associated with infant anthropometry or growth velocity before 6 mo.

Methods: Breast milk was collected from Mam-Mayan mothers (n = 114) at both early (2-46 d) and established (4-6 mo) lactation.

Endocannabinoid Metabolome Characterization of Milk from Guatemalan Women Living in the Western Highlands.

Background: Recognized as the gold-standard ideal fare, human milk has a unique composition that meets infants' needs throughout development. Endocannabinoids and endocannabinoid-like compounds [endocannabinoid metabolome (ECM)] are endogenous lipid mediators derived from long-chain polyunsaturated fatty acids. Based on animal models, it has been proposed that endocannabinoid arachidonoyl glycerol (AG) plays a role in establishing the suckling response during lactation.

Infant growth faltering linked to subclinical mastitis, maternal faecal-oral contamination, and breastfeeding.

Infant growth faltering occurs in breastfed infants <6 months of age. The possibility that maternal health status contributes to this growth faltering is underexplored. We investigated whether (a) subclinical mastitis (SCM), an asymptomatic inflammation of the breast, (b) maternal intestinal nematode and protozoan infections, indicators of faecal-oral contamination, or (c) poor breastfeeding practices increased the odds of stunting (length-for-age z-score < -2SD), underweight (weight-for-age z-score < -2SD), or low head circumference (head circumference-for-age z-score < -2SD) in breastfed infants in rural indigenous communities in Guatemala.

Several problem nutrients are identified in the complementary diet of 6 to 11 month old breastfed children in Western Guatemala.

Background And Objectives: The failure of infants in developing countries to meet nutrient intake recommendations is well documented. The objective of this study was to assess the nutritional adequacy and identify problem nutrients of the diets of Guatemalan infants with continued breastfeeding.

Methods And Study Design: A single previous-day dietary recall was collected from a convenience sample of 94 mothers of infants aged 6-11 mo attending a public health clinic in the urban area of Quetzaltenango, Guatemala.

Subclinical mastitis (SCM) and proinflammatory cytokines are associated with mineral and trace element concentrations in human breast milk.

The possibility that either subclinical mastitis (SCM), an inflammatory condition of the breast, or elevations in breast milk proinflammatory cytokines alter breast milk mineral and trace element composition in humans has not been investigated. In this cross-sectional study, breast milk samples (n=108) were collected from Guatemalan Mam-Mayan mothers at one of three stages of lactation (transitional, early and established), and categorized as SCM (Na:K >0.6) or non-SCM (Na:K ≤0.

Perspective: What Makes It So Difficult to Mitigate Worldwide Anemia Prevalence?

Anemia can be related to decreased production or increased loss of erythrocytes, or both, leading to many underlying and often overlapping causes. A largely cereal-based diet with plenty of phytates, polyphenols, and other ligands that inhibit intestinal iron absorption predominated in preindustrial Europe and predominates in present-day developing countries alike. In both situations, we find poor hygienic conditions, which frequently lead to anemia of inflammation.

Minerals and Trace Elements in Human Breast Milk Are Associated with Guatemalan Infant Anthropometric Outcomes within the First 6 Months.

Background: Breast milk is the recommended source of nutrients for infant growth, but its adequacy to meet infants' mineral and trace element needs is unknown.

Objectives: We used breast-milk mineral and trace element concentrations of Guatemalan mothers at 3 lactation stages to estimate total daily intakes and to determine whether intakes were associated with early infant growth.

Methods: In this cross-sectional study, breast-milk samples were collected from Mam-Mayan mothers during transitional (5-17 d, n = 56), early (18-46 d, n = 75), and established (4-6 mo, n = 103) lactation; z scores for weight (WAZ), length (LAZ), and head circumference (HCAZ) were measured.

Effects of maternal hydration status on the osmolality of maternal milk.

Background: It has been demonstrated that human milk osmolality (Mosm) is regulated within an established range, typically 290 to 300 mOsm/kg, and appears to be resistant to effects of maternal dehydration, as refl ected by high urinary osmolality (Uosm).

Objective: To determine the degree of association between Mosm and Uosm at a common point in time, as well as the reproducibility of both measures over a one-week interval of sampling.

Methods: Mosm and Uosm were measured with a Vogel Löser 450 osmometer on samples of the respective biological fluids collected concurrently in 31 lactating women, with infants aged between 30 and 340 days.

Normative Fecal Calprotectin Concentrations in Guatemalan Preschoolers Are High Relative to Children Reported Elsewhere.

Background: Calprotectin is a fecal marker of intraintestinal inflammation derived from activated enteric neutrophils and macrophages. It is useful as a clinical marker in inflammatory bowel diseases; furthermore, it may have a role in public health epidemiology.

Objectives: The aim of the study was to describe the distribution of fecal calprotectin in Guatemalan preschool children sharing a common institutional diet; to relate it collectively to pediatric distributions in other geographic settings, and individually to concomitant indicators of intestinal infection or colonization and other descriptive features of the child.

The potential double-burden of vitamin A malnutrition: under- and overconsumption of fortified table sugar in the Guatemalan highlands.

Background/objectives: In Guatemala, population-wide vitamin A fortification of table sugar has been operating for two decades. The objective of this study was to estimate the adequacy of vitamin A intakes in pregnant and lactating women from low-income, urban and rural communities.

Subjects/methods: One or two previous-day dietary recalls were collected in a convenience sample of 234 pregnant and lactating women in the Western Highlands of Guatemala.