Micronutrients are essential to sustain life and for optimal physiological function. Widespread global micronutrient deficiencies (MNDs) exist, with pregnant women and their children under 5 years at ...the highest risk. Iron, iodine, folate, vitamin A, and zinc deficiencies are the most widespread MNDs, and all these MNDs are common contributors to poor growth, intellectual impairments, perinatal complications, and increased risk of morbidity and mortality. Iron deficiency is the most common MND worldwide and leads to microcytic anemia, decreased capacity for work, as well as impaired immune and endocrine function. Iodine deficiency disorder is also widespread and results in goiter, mental retardation, or reduced cognitive function. Adequate zinc is necessary for optimal immune function, and deficiency is associated with an increased incidence of diarrhea and acute respiratory infections, major causes of death in those <5 years of age. Folic acid taken in early pregnancy can prevent neural tube defects. Folate is essential for DNA synthesis and repair, and deficiency results in macrocytic anemia. Vitamin A deficiency is the leading cause of blindness worldwide and also impairs immune function and cell differentiation. Single MNDs rarely occur alone; often, multiple MNDs coexist. The long-term consequences of MNDs are not only seen at the individual level but also have deleterious impacts on the economic development and human capital at the country level. Perhaps of greatest concern is the cycle of MNDs that persists over generations and the intergenerational consequences of MNDs that we are only beginning to understand. Prevention of MNDs is critical and traditionally has been accomplished through supplementation, fortification, and food-based approaches including diversification. It is widely accepted that intervention in the first 1,000 days is critical to break the cycle of malnutrition; however, a coordinated, sustainable commitment to scaling up nutrition at the global level is still needed. Understanding the epidemiology of MNDs is critical to understand what intervention strategies will work best under different conditions.
Micronutrients, vitamins and minerals accessible from the diet, are essential for biologic activity. Micronutrient status varies widely throughout pregnancy and across populations. Women in ...low-income countries often enter pregnancy malnourished, and the demands of gestation can exacerbate micronutrient deficiencies with health consequences for the fetus. Examples of efficacious single micronutrient interventions include folic acid to prevent neural tube defects, iodine to prevent cretinism, zinc to reduce risk of preterm birth, and iron to reduce the risk of low birth weight. Folic acid and vitamin D might also increase birth weight. While extensive mechanistic and association research links multiple antenatal micronutrients with plausible materno-fetal health advantages, hypothesized benefits have often been absent, minimal or unexpected in trials. These findings suggest a role for population context in determining health responses and filling extensive gaps in knowledge. Multiple micronutrient supplements reduce the risks of being born with low birth weight, small for gestational age or stillborn in undernourished settings, and justify micronutrient interventions with antenatal care. Measurable health effects of gestational micronutrient exposure might persist into childhood but few data exists on potential long-term benefits. In this Review, we discuss micronutrient intake recommendations, risks and consequences of deficiencies, and the effects of interventions with a particular emphasis on offspring.
Abstract Background Does preschool height predict adult stature in undernourished settings? The extent to which preschool length or height forecasts young adult stature is unclear in chronically ...undernourished populations. Methods In 2006-8, we assessed height in a cohort of 2074 young adults, aged 16–23 years, in rural Nepal who, as preschoolers ( ≤ 4 year), were measured at baseline and again 16 months later during a vitamin A supplementation trial in 1989-91. We assessed by linear regression the ability of preschool length (L, measured < 24 mo) or height (Ht, 24–59 mo), at each year of age to predict 16–23 year old height, adjusted for month of young adult age, interval duration (in months), caste, preschool weight-for-height z-score and, in young women, time since menarche, marriage status and pregnancy history. Results Young women were a mean of 0.81, 1.11, 0.82, 0.24, 0.44 cm taller (all p < 0.01) and young men, 0.84, 1.18, 0.74, 0.64 and 0.48 cm taller (all p < 0.001) per cm of attained L/Ht at each successive preschool year of age and, overall, were 2.04 and 2.40 cm taller for each unit increase in preschool L/Ht z-score (L/HAZ) (both p < 0.001). Coefficients were generally larger for 16-month follow-up measurements. The percent of young adult height attained by children with normal L/HAZ (>-1) increased from 38–40% mid-infancy to ∼ 69–74% by 6 years of age. By 3–6 years of age heights of stunted children (L/HAZ<-2) were consistently ∼ 4–7% lower in their young adult height versus normal statured children. There was no effect of preschool vitamin A receipt. Conclusions Shorter young children become shorter adults but predictive effects can vary by sex, age assessed, and may be influenced by year or season of measurement.
Early and exclusive breastfeeding may reduce neonatal and post-neonatal mortality in low-resource settings. However, prelacteal feeding (PLF), the practice of giving food or liquid before ...breastfeeding is established, is still a barrier to optimal breastfeeding practices in many South Asian countries. We used a prospective cohort study to assess the association between feeding non-breastmilk food or liquid in the first three days of life and infant size at 3-5 months of age.
The analysis used data from 3,332 mother-infant pairs enrolled in a randomized controlled trial in northwestern rural Bangladesh conducted from 2018 to 2019. Trained interviewers visited women in their households during pregnancy to collect sociodemographic data. Project staff were notified of a birth by telephone and interviewers visited the home within approximately three days and three months post-partum. At each visit, interviewers collected data on breastfeeding practices and anthropometric measures. Infant length and weight measurements were used to produce length-for-age (LAZ), weight-for-age (WAZ), and weight-for-length (WLZ) Z-scores. We used multiple linear regression to assess the association between anthropometric indices and PLF practices, controlling for household wealth, maternal age, weight, education, occupation, and infant age, sex, and neonatal sizes.
The prevalence of PLF was 23%. Compared to infants who did not receive PLF, infants who received PLF may have a higher LAZ (Mean difference (MD) = 0.02 95% CI: -0.04, 0.08) score, a lower WLZ (MD=-0.06 95% CI: -0.15, 0.03) score, and a lower WAZ (MD=-0.02 95% CI: -0.08, 0.05) score at 3-5 months of age, but none of the differences were statistically significant. In the adjusted model, female sex, larger size during the neonatal period, higher maternal education, and wealthier households were associated with larger infant size.
PLF was a common practice in this setting. Although no association between PLF and infant growth was identified, we cannot ignore the potential harm posed by PLF. Future studies could assess infant size at an earlier time point, such as 1-month postpartum, or use longitudinal data to assess more subtle differences in growth trajectories with PLF.
ClinicalTrials.gov: NCT03683667 and NCT02909179.
Hepatitis E virus (HEV) is a major cause of illness and of death in the developing world and disproportionate cause of deaths among pregnant women. Although HEV vaccine trials, including trials ...conducted in populations in southern Asia, have shown candidate vaccines to be effective and well-tolerated, these vaccines have not yet been produced or made available to susceptible populations. Surveillance data collected during 2001-2007 from >110,000 pregnancies in a population of ≈650,000 women in rural Bangladesh suggest that acute hepatitis, most of it likely hepatitis E, is responsible for ≈9.8% of pregnancy-associated deaths. If these numbers are representative of southern Asia, as many as 10,500 maternal deaths each year in this region alone may be attributable to hepatitis E and could be prevented by using existing vaccines.
Knowledge of the extent of vitamin A (VA) deficiency (D) is critical for identifying high-risk populations and mobilizing resources for prevention. Yet, all estimates are necessarily imperfect, often ...based on assumptions in the absence of data. In 1995, the World Health Organization estimated 254 million children to be VA-deficient and 2.8 million to have xerophthalmia. Subsequently, estimates were changed to 75–140 million and 3.3 million, respectively. Although both sets are consistent with a problem of enormous magnitude, the discrepancies also created uncertainty. The present analysis indicates there are ∼127 million and 4.4 million preschool children with VAD (serum retinol < 0.70 μmol/L or displaying abnormal impression cytology) and xerophthalmia, respectively. More than 7.2 million pregnant women in the developing world are VA-deficient (serum or breast-milk vitamin A concentrations < 0.70 μmol/L), and another 13.5 million have low VA status (0.70–1.05 μmol/L); >6 million women develop night blindness (XN) during pregnancy annually. Roughly 45% of VA-deficient and xerophthalmic children and pregnant women with low-to-deficient VA status live in South and Southeast Asia. These regions harbor >60% of all cases of maternal XN, three fourths of whom seem to live in India. Africa accounts for 25–35% of the global cases of child and maternal VAD; about 10% of all deficient persons live in the eastern Mediterranean region, 5–15% live in the Western Pacific and ∼5% live in the Region of the Americas. VA prophylaxis seems to be preventing the number of deficient preschool children from increasing while probably reducing rates of blindness and mortality. Greater effort is needed to assess and prevent VAD and its disorders, particularly among pregnant and lactating women. J. Nutr. 132: 2857S–2866S, 2002.
The 2015 earthquake in Nepal caused massive damages and triggered relief activities to minimize human suffering. The post-earthquake nutrition and food security situation in the hardest hit areas ...remains uncertain.
Two national cross-sectional surveys were conducted in 2014 and 2016 among households (HH) with pre-school aged children or newly married women. Of the 21 village development committees (VDCs) included in this sample, 7 fell within "earthquake-affected" areas. This paper presents data from 982 HH, 1015 women, and 883 children from 2014 and 1056 HH, 1083 women, and 998 children from 2016 living in these areas, with longitudinal overlap of about 55%. Prevalence estimates and 95% confidence intervals were calculated, and logistic regression was used to calculate p-values, both using robust estimates of standard errors to account for clustering.
From 2014 to 2016, child wasting (weight-for-height z score <-2) fell from 4.5% (95% CI 3.3%- 6.1%) to 2.1% (1.4%- 3.1%) and food insecurity (assessed using the household food insecurity access scale) dropped from 17.6% (11.7%- 25.6%) to 12.4% (6.9%- 21.2%). Child stunting prevalence remained similar at both time-points. Improvements were also evident in dietary diversity and breastfeeding indicators.
Nutrition and food security conditions remained comparable or improved one year after the earthquake despite evidence of structural and other damage. Livelihood resilience to shocks and/or effective nutrition, food or health interventions may have helped buffer the impact on nutrition, although this hypothesis requires further exploration.
Dietary diversity scores and dichotomous indicators derived from them are widely used to assess dietary quality, and specific scoring methods have been recommended for women and 6- to 23-mo-old ...children. However, there is no specific score recommended for older children and the effect of seasonal dietary changes on score performance is not well documented.
We assessed performance of 2 recommended dietary diversity scores as indicators of dietary quality over 3 seasons.
We conducted 7 repeat 24-h dietary recalls among 4- to 8-y-old rural Zambian children (n = 200) over 6 mo. Dietary diversity was assessed using a 7-food group score for assessing infant and young child feeding (DDS-IYCF) and a 10-food group score for use among women of reproductive age (DDS-W). Micronutrient intake adequacy was described by mean probability of adequacy (MPA) over 11 micronutrients. Longitudinal models were fit to test the association between each score and MPA overall and by season. Receiver operating characteristic (ROC) curves were used to describe indicator performance of each score.
Mean ± SE scores were 4.11 ± 0.03 for DDS-IYCF and 4.39 ± 0.03 for DDS-W. Both scores varied by season, but DDS-W better reflected seasonal dietary changes. Across seasons, MPA increased 1–6 percentage points/unit increase in DDS-IYCF or 1–10 percentage points for DDS-W (P < 0.05). Score performance as a predictor of MPA > 0.75 was moderate, with area under the ROC curve values by season ranging from 0.63 to 0.77 for DDS-IYCF and from 0.66 to 0.72 for DDS-W.
DDS-W performed better than DDS-IYCF in characterizing seasonal variability and micronutrient adequacy among rural Zambian children.
Micronutrient deficiencies are common among women in low-income and middle-income countries. Data from randomised trials suggest that maternal multiple micronutrient supplementation decreases the ...risk of low birthweight and potentially improves other infant health outcomes. However, heterogeneity across studies suggests influence from effect modifiers. We aimed to identify individual-level modifiers of the effect of multiple micronutrient supplements on stillbirth, birth outcomes, and infant mortality in low-income and middle-income countries.
This two-stage meta-analysis of individual patient included data from 17 randomised controlled trials done in 14 low-income and middle-income countries, which compared multiple micronutrient supplements containing iron-folic acid versus iron-folic acid alone in 112 953 pregnant women. We generated study-specific estimates and pooled subgroup estimates using fixed-effects models and assessed heterogeneity between subgroups with the χ2 test for heterogeneity. We did sensitivity analyses using random-effects models, stratifying by iron-folic acid dose, and exploring individual study effect.
Multiple micronutrient supplements containing iron-folic acid provided significantly greater reductions in neonatal mortality for female neonates compared with male neonates than did iron-folic acid supplementation alone (RR 0·85, 95% CI 0·75–0·96 vs 1·06, 0·95–1·17; p value for interaction 0·007). Multiple micronutrient supplements resulted in greater reductions in low birthweight (RR 0·81, 95% CI 0·74–0·89; p value for interaction 0·049), small-for-gestational-age births (0·92, 0·87–0·97; p=0·03), and 6-month mortality (0·71, 0·60–0·86; p=0·04) in anaemic pregnant women (haemoglobin <110g/L) as compared with non-anaemic pregnant women. Multiple micronutrient supplements also had a greater effect on preterm births among underweight pregnant women (BMI <18·5 kg/m2; RR 0·84, 95% CI 0·78–0·91; p=0·01). Initiation of multiple micronutrient supplements before 20 weeks gestation provided greater reductions in preterm birth (RR 0·89, 95% CI 0·85–0·93; p=0·03). Generally, the survival and birth outcome effects of multiple micronutrient supplementation were greater with high adherence (≥95%) to supplementation. Multiple micronutrient supplements did not significantly increase the risk of stillbirth or neonatal, 6-month, or infant mortality, neither overall or in any of the 26 examined subgroups.
Antenatal multiple micronutrient supplements improved survival for female neonates and provided greater birth-outcome benefits for infants born to undernourished and anaemic pregnant women. Early initiation in pregnancy and high adherence to multiple micronutrient supplements also provided greater overall benefits. Studies should now aim to elucidate the mechanisms accounting for differences in the effect of antenatal multiple micronutrient supplements on infant health by maternal nutrition status and sex.
None.
Dietary quality and diversity reflect adequacy of vitamin A. Both can deteriorate in response to economic crises. Although the nutritional consequences of the 2008 world food price crisis remain ...unclear, past studies of diet, status, and socioeconomic standing under usual (deprived) and unusually disruptive times suggest dietary quality and vitamin A status decline in mothers and young children. This is presumably the result of shifting diets to include less preformed vitamin A-rich animal source foods and, to a lesser extent, vegetables and fruits. Cross-sectional assessments of diet, deficiency, and socioeconomic status in a number of countries and surveillance data collected during the Indonesian economic crisis of 1997-8 indicate that the prevalence of vitamin A deficiency, night blindness, and other related disorders (e.g., anemia) may have increased during the 2008 crisis, and that it might not have necessarily recovered once food prices waned later in 2008. Lost employment may be a factor in slow nutritional recovery, despite some easing of food prices. Vitamin A deficiency should still be preventable amid economic instabilities through breast feeding promotion, vitamin A supplementation, fortification of foods targeted to the poor, and homestead food production that can bolster income and diversify the diet.