To compare physiologically based serum hepcidin and ferritin thresholds for iron deficiency in adult female and male blood donors, we analysed laboratory results obtained during screening for a blood donor study. In 907 apparently healthy blood donors, we examined the relationships of hepcidin and ferritin with five indicators of the onset of iron-deficient red blood cell production: haemoglobin (Hb), soluble transferrin receptor (sTfR), erythrocyte zinc protoporphyrin (ZPP), reticulocyte haemoglobin content (Retic-Hb) and mean corpuscular volume (MCV). Serum hepcidin and ferritin were correlated (Pearson's r = 0.69, p = <0.001 females; r = 0.65, p < 0.001, males). At lower serum hepcidin and ferritin concentrations, Hb, Retic-Hb and MCV decreased and sTfR and ZPP increased. Using restricted cubic spline models, the hepcidin thresholds for iron deficiency in adult female donors 18-49 years, 50-75 years and all male blood donors 18-75 years old were 13.9, 24.8 and 28.8 μg/L respectively. The corresponding ferritin thresholds were 25.4, 30.7 and 32.5 μg/L respectively. Among blood donors 18-50 years old, serum hepcidin and ferritin thresholds for iron deficiency were lower in women than in men but were similar after 50 years of age. In conclusion, among adult blood donors, serum hepcidin and ferritin thresholds are similarly effective for detecting iron deficiency, especially among women.

Centers for Disease Control and Prevention's 'National Report on Biochemical Indicators of Diet and Nutrition in the US Population' provides nutritional status assessment by presenting blood and urine concentrations of diet and nutrition biomarkers in a representative sample of the US population ≥1 y participating in the NHANES. Earlier reports contained information for 27 (1999-2002) and 58 (2003-2006) biomarkers. We aimed to provide an overview of the 2026 report, which covers data for ≤131 biomarkers since 1999, with 50 biomarkers from August 2021 to August 2023. Concentrations over time by cycle are stratified by dietary supplement use, reference interval concentrations focus on tail percentiles, and concentrations grouped by age, sex, and/or race and Hispanic origin demonstrate demographic differences. The report is intended for agencies and organizations involved in developing nutrition policies and monitoring their effects. It provides easily accessible, comprehensive nutritional biomarker data for the US population during the last 24 y.

Iron deficiency (ID) is the most predominant nutritional deficiency globally. The current CDC iron guideline for ID screening uses serum ferritin (Ft) ≤15 μg/L based on bone-marrow assessment. We aimed to evaluate physiologically based Ft thresholds for defining ID in children aged 5 to 14 years. Ferritin and hemoglobin (Hb) data were analyzed from 3765 apparently healthy (no inflammation, infection, risk of iron overload or potential liver disease) US children, and an indicator of iron-deficient erythropoiesis such as erythrocyte zinc protoporphyrin (ZPP). Nonlinear ferritin concentration curves (Hb-Ft, ZPP-Ft) and differential equations were applied to identify ferritin thresholds at ID onset with inflection minima and plateau for each iron analyte. Mean age was 10.3 years. The ferritin curve inflection for ID occurred at 23.9 μg/L (95% confidence interval, 21.7–27.3) with Hb and 25.0 μg/L (23.8–27.1) with ZPP. No inter-analyte (P = 0.67), age (P = 0.49 with Hb, P = 0.95 with ZPP), or sex (P = 0.39) differences observed. ID prevalence was 9.0% (7.3–10.7), and ID anemia (IDA) 0.5% (0.3–0.8) using CDC thresholds, versus ID 30.0% (27.4–32.5) and IDA 1.0% (0.6–1.3) % using physiologically based thresholds. Physiologically based ferritin thresholds for ID onset were consistently higher than current CDC thresholds across iron analyte, age, and sex. IDA remained unchanged with physiologically based thresholds, suggesting that anemia is not an adequate proxy for ID screening, and clinicians should consider higher ferritin as a functional threshold for defining ID in children aged 5-14 years.

Background:Tracking the prevalence of imbalances for essential nutrients over time provides insight into nutritional status changes and highlights vulnerabilities of demographic subgroups. Consolidated information for a broad range of biomarkers in the US population is missing. Objectives:We aimed to describe nutritional deficiency and excess prevalence trends for 12 biomarkers of water- and fat-soluble vitamins and iron status in the US population participating in the NHANES 1999-2023 after adjusting for demographic changes over time. Methods:We estimated the prevalence of deficiency (vitamins A, B-6, B-12, C, D, and E, as well as iron), insufficiency [vitamins B-6, B-9 (folate), B-12, C, and D], and excess (vitamins A and D as well as iron). We assessed trends as overall change in prevalence using logistic regression (unadjusted and adjusted for age, sex, and race/Hispanic origin) and as linear trend (if overall change was significant). Results:After adjusting for demographic changes, we observed small (typically <5 percentage points) temporal changes (significant linear trends) in the prevalence of deficiency and/or insufficiency for vitamin B-12 and methylmalonic acid (≥20 y), and for vitamin E and 25-hydroxyvitamin D (25OHD) (≥6 y). The prevalence of folate insufficiency (red blood cell folate (RBF) <748 nmol/L) and iron deficiency (ferritin ≤15 ng/mL) increased from 15.7% to 21.4% and from 11.6% to 17.4%, respectively, in women of reproductive age. The prevalence of excess vitamin D (25OHD >125 nmol/L) increased from <1% to 8.06% in persons ≥6 y, with the highest prevalence in adult subgroups (16.2% in supplement users, 13.2% in females, and 12.3% in non-Hispanic White persons). Conclusions:The large increases in excess 25OHD concentrations and modest increases in low ferritin and RBF concentrations merit attention and highlight the importance of providing gold standard data to continuously monitor the nutritional status of the US population and of subpopulations.

BACKGROUND:Anemia remains a significant health problem among Burkinabé adolescents aged 10-19 y. However, population-based information on its correlates remains limited. OBJECTIVES:This study assessed the burden of anemia, iron deficiency (ID), and iron deficiency anemia (IDA), and factors associated with these outcomes among Burkinabé adolescents. METHODS:We used data from 689 boys and 724 girls who participated in the nationally representative (except Sahel region), population-based 2020 Burkina Faso National Micronutrient Survey to conduct hierarchical logistic multivariable regression identifying underlying, immediate, and biological factors associated with adolescent anemia, ID, and IDA, with statistical significance set at P < 0.05. RESULTS:Anemia prevalence was 31% among boys and 29% among girls. Prevalences of ID and IDA were 20% and 10%, respectively, among boys, and 24% and 12%, respectively, among girls. From the underlying factors assessed, household wealth was associated with all 3 outcomes in boys. Among immediate factors, older age (14-19 y) was associated with all 3 outcomes for girls. ID and recent malaria infection were also associated with higher odds of anemia in both populations, whereas vitamin A deficiency was associated with higher odds of anemia among boys, as well as higher odds of ID and IDA for girls. CONCLUSIONS:Anemia, ID, and IDA etiology among Burkinabé adolescents is multifactorial, with complex relationships involving household and individual characteristics, as well as biological factors. A multisectoral approach to adolescent-focused policies and programs, in addition to direct nutrition interventions, may be effective in reducing anemia, ID, and IDA among adolescents.

CDC’s National Report on Biochemical Indicators of Diet and Nutrition in the U.S. Population provides nutritional status assessment by presenting blood and urine concentrations of diet-and-nutrition biomarkers in a representative sample of the U.S. population ≥1 y participating in the National Health and Nutrition Examination Survey (NHANES). Earlier reports contained information for 27 (1999–2002) and 58 (2003–2006) biomarkers. We aim to provide an overview of the 2026 report, which covers data for ≤131 biomarkers since 1999, with 50 biomarkers from August 2021–August 2023. Concentrations over time by cycle are stratified by dietary supplement use, reference interval concentrations focus on tail percentiles, and concentrations grouped by age, sex, and/or race/Hispanic origin demonstrate demographic differences. The report is intended for agencies and organizations involved in developing nutrition policies and monitoring their effects. It provides easily accessible, comprehensive nutritional biomarker data for the U.S. population during the last 24 y.

Background:The National Health and Nutrition Examination Survey (NHANES) has monitored biomarkers for 4 key nutrients important for pregnancy outcomes, neurological development, and healthy growth-folate, vitamin D, iodine, and iron-during most survey cycles from 1999 to 2000 through August 2021-August 2023 as part of the continuous NHANES. These biomarker data offer a unique opportunity to assess long-term trends in the US population. Objectives:This study aimed to describe concentration trends for 7 biomarkers/indicators after adjusting for demographic changes over time. Methods:We used the following NHANES data: serum folate (SFOL) and red blood cell folate (RBF) for persons aged ≥3 y and women of reproductive age (WRA, 12-49 y) for 1999-August 2023 (except 2017-2018), serum 25-hydroxyvitamin D (25OHD) for persons aged ≥3 y for 2001-August 2023, urine iodine (UI) for persons aged ≥3 y for 2001-2018, and serum ferritin [(FER) and FER adjusted for inflammation (FERadj)], serum soluble transferrin receptor, and body iron index (BII) for WRA and children aged 1-5 y for 2003-August 2023 (except 2011-2014). We assessed trends as overall concentration change using logistic regression (unadjusted and adjusted for age, sex, and race and Hispanic origin) and as a linear trend if the overall change was significant. Results:After adjusting for demographic changes, mean concentrations of all 7 biomarkers/indicators showed significant overall temporal changes (except for FER in children and BII in WRA) and significant linear trends (except for FERadj in children). SFOL (∼25%-30%), RBF (∼10%), and UI (∼25%-30%) concentrations decreased, whereas 25OHD (∼20%) concentrations increased. FER concentrations decreased in WRA (∼15%) and remained unchanged in children. Conclusions:Considering the long monitoring period, biomarker changes were moderate. Nonetheless, these changes highlight the need to address declining iodine, iron, and folate status in WRA and increasing vitamin D status in supplement users.

BACKGROUND:Clinical data, such as electronic health records, may be useful for iron deficiency (ID) surveillance. OBJECTIVE:Our objective was to compare iron and hematologic indicators commonly measured in clinical settings to the World Health Organization (WHO)-recommended iron indicator, serum ferritin (SF), to assess ID among a population of adult women aged 20-44 y. METHODS:We evaluated sensitivity, specificity, and area under the receiver operating characteristics (ROC) curve of iron and hematologic indicators commonly measured in clinical settings for ID: hemoglobin (Hb) <120 g/L (nonpregnant), Hb <110 g/L or <105 g/L (pregnant, depending on trimester); mean corpuscular volume (MCV) <80 fL; serum iron <40 μg/dL; total iron binding capacity (TIBC) >400 μg/dL; transferrin saturation (TSAT) <15%, compared with a reference (SF <30 μg/L for pregnant women and inflammation-adjusted SF <15 μg/L for nonpregnant women) using the United States NHANES 2003-2006 and 2017-2018. RESULTS:Among pregnant women (n = 730), sensitivity ranged from 8.1% (MCV) to 87.2% (TIBC), and specificity ranged from 63.0% (TIBC) to 97.5% (MCV), and area under the ROC curve ranged from 0.553 (MCV) to 0.816 (TIBC). Among nonpregnant women (n = 3345), sensitivity ranged from 32.1% (MCV) to 71.9% (TSAT), specificity ranged from 85.7% (TIBC) to 96.1% (Hb), and area under the ROC curve ranged from 0.785 (MCV) to 0.853 (TSAT). ID prevalence using clinical indicators varied widely compared with prevalence using SF. Among pregnant women, ID prevalence ranged from 6.7% (95% confidence interval [CI]: 3.6, 9.7) (MCV) to 51.8% (95% CI: 46.0, 57.5) (TIBC), compared with 47.0% (95% CI: 39.5, 54.5) using SF. Among nonpregnant women, prevalence of ID using clinical indicators ranged from 6.4% (95% CI: 5.4, 7.3) (MCV) to 24.7% (95% CI: 22.4, 26.9) (TSAT), compared with 15.1% (95% CI: 13.4, 16.6) using SF. CONCLUSIONS:Iron and hematologic indicators routinely used in clinical settings can under- or overestimate ID, suggesting that they are not ideal for ID surveillance.

This paper defines the double burden of malnutrition as occurring when over- and undernutrition coexist within a household. It is most common in countries undergoing the nutrition transition where cheap and accessible food is often of poor quality. This brief narrative review examines four cycles of reports from the Epidemiological Health and Nutrition Surveillance System (SIVESNU, Spanish acronym) in Guatemala between 2015–2018/19, examining the following indicators: overall double burden of stunting among children aged ≤59 months and overweight or obesity among women aged 15–49 years in the same household, and individual stunting, overweight, and obesity by indigenous/non-indigenous ethnicity. The review also incorporates double burden prevalence in Guatemala from the literature since 1995. In 1995, the double burden prevalence was 13.4

Background School food environments may play an important role in shaping children's dietary habits, health, and nutrition. Objectives This study aimed to evaluate associations between the school food environment and nutrition among in-school adolescents in Ghana. Methods Data were collected in Ghana in 2022 in a national nutrition and health survey of adolescents attending junior (JHS) and senior high schools (SHS). Foods observed on campus or reported in the dietary recall were aggregated, a composite Adolescent Dietary Diversity Score (ADDS) was derived, and the proportion achieving minimum dietary diversity was estimated. Multi-level regression models were used to assess associations between a ranked school food environment score (FES) and nutrition outcomes. Results The number of food groups served or available for purchase was 6.2 in JHS and 8.1 in SHS ( P -value <.0001). The mean (95% CI) FES was 10.9 (10.1, 11.7) at JHS and 14.3 (13.6, 14.9) at SHS. ADDS ranged from 4.1 to 4.8 across strata. Higher FES was positively associated with ADDS and minimum dietary diversity among SHS students and negatively associated with anemia in girls and boys. Girls from high FES schools had 24% lower odds of anemia (OR: 0.76, 95% CI: 0.63, 0.93) while boys had 46% lower odds (OR: 0.54, 95% CI: 0.34, 0.84) compared to students in low FES schools. Conclusions Higher FES was associated with greater dietary diversity among SHS students and lower odds of anemia in girls and boys, suggesting that the school food environment may play a role in determining nutrition outcomes.

BACKGROUND:Diagnosis of iron deficiency commonly relies on measurement of serum ferritin concentrations. WHO guidelines identify serum ferritin thresholds for iron deficiency among healthy individuals of less than 15 μg/L for women and less than 12 μg/L for children under 5 years, based on expert opinion. We report thresholds for iron deficiency for apparently healthy non-pregnant women and young children based on physiological indicators. METHODS:We performed secondary analyses of cross-sectional data from women (aged 15-49 years) and children (aged 6-59 months) from 12 countries in Africa, Asia, Europe, and central America from available surveys (2007-19). Using haemoglobin and soluble transferrin receptor concentrations as individual-level indicators of iron deficiency, we identified country-specific serum ferritin thresholds. We conducted multivariate meta-analysis using individual participant data to assess multinational heterogeneity and intercountry consistency. FINDINGS:Data were collected from July, 2007 to March, 2019. 18 251 individuals (13 864 women and 4387 children) were included in the final analysis. The thresholds of pooled serum ferritin levels corresponding to the starting point of decline in circulating haemoglobin concentrations were 24·8 μg/L (95% CI 24·4-25·2) for women and 22·1 μg/L (20·8-23·4) for children based on the national survey data from 12 countries. The thresholds were consistent among countries (pheterogeneity: women=0·73, children=0·43) but median serum ferritin concentrations and lower 5% reference ranges differed. In all countries, the prevalence of iron deficiency was higher using physiologically based thresholds than that using WHO current guidelines for women (36·0% [95% CI 25·3-46·8] vs 20·1% [11·5-28·7], p<0·0001) and for children (34·2% [24·3-44·1] vs 16·6% [11·2-22·0], p<0·0001). INTERPRETATION:These results provide evidence that the prevalence of iron deficiency as indicated by physiological measures is substantially higher than those based on current WHO guidelines. The consistency of physiologically based serum ferritin thresholds in apparently healthy women and young children offers a potential means to achieve evidence-informed coordination in thresholds for iron deficiency across populations. The use of physiologically based serum ferritin thresholds could help in detecting the clinical and functional outcomes of iron deficiency. FUNDING:None.

World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) guidelines recommend a serum ferritin (SF) threshold for iron deficiency (ID) of <15μg/L and ≤ 15μg/L, respectively, for healthy adults aged 15–60+ years. In apparently healthy adults, we used SF at which the circulating hemoglobin (Hb) begins to decrease and the erythrocyte zinc protoporphyrin (eZnPP) begins to increase as a potential physiological indicator of the ID threshold. We analyzed data for 5169 men and 6957 non-pregnant women, aged 15–90 years, from the Third National Health and Nutrition Examination Survey (NHANES III, 1988–1994). Physiologically based SF thresholds for ID were higher than WHO and CDC recommendations (P<0.001 for all). For men and postmenopausal women, SF thresholds corresponding to the initial decline in circulating Hb did not differ significantly, with an overall threshold of 32.6 μg/L (95% CI: (27.4, 37.7)). The SF threshold for premenopausal women was 24.8 μg/L (23.4, 26.9), lower than that for men and postmenopausal women (P<0 .0001). The difference between SF physiologically based thresholds in men and older women, with basal iron losses, compared to younger women, with menstrual/basal iron losses, provides evidence that hepcidin regulation of iron homeostasis controls the onset for ID in healthy adults. Clinically, use of higher physiologically based SF thresholds for ID for adults may lead to earlier diagnosis of increased blood loss.

Serum ferritin (SF) concentration is the most widely used indicator for iron deficiency (ID). During pregnancy, the World Health Organization recently recommended SF thresholds for ID of <15 mu g/L for the first trimester of pregnancy, based on expert opinion, and made no recommendations for the second and third trimesters. We examined the relationship of SF with 2 independent indicators of the onset of iron-deficient erythropoiesis, hemoglobin and soluble transferrin receptor 1, in cross-sectional data from US National Health and Nutrition Examination Survey for 1999 to 2010 and 2015 to 2018. We included 1288 pregnant women aged 15 to 49 years and excluded women with inflammation or potential liver disease. We used restricted cubic spline (RCS) regression analysis to determine SF thresholds for iron-deficient erythropoiesis. SF decreased during pregnancy; geometric mean SF was higher during the first and lower during the second and third trimesters. Using RCS analysis, the SF thresholds identified during pregnancy were <25.8 mu g/L (18.1-28.5) during first trimester, <18.3 mu g/L (16.3-22.9) during second trimester, and <19.0 mu g/L (14.4- 26.1) during third trimester. These SF threshold levels track concentrations of hepcidin, the iron-regulatory hormone controlling the mobilization of iron stores. An SF concentration of <15 mu g/L as the criterion for ID may underestimate the true prevalence of ID throughout pregnancy. In our study, an additional 1 of every 10 pregnant women would be recognized as iron deficient by using the physiologically based thresholds at SF of similar to 25 mu g/L during the first and similar to 20 mu g/L during the second and third trimesters.