Iron in child obesity. Relationships with inflammation and metabolic risk factors

Antioxidant Supplementation in Childhood Obesity: A Path to Improved Metabolic Health?

Childhood obesity is linked to heightened oxidative stress, a key driver of endothelial dysfunction, inflammation, and metabolic complications. Antioxidants, including Vitamins C and E, are vital in neutralizing free radicals and mitigating oxidative damage. This non-systematic review examines the potential advantages of antioxidant supplementation in pediatric obesity, focusing on its effects on vascular health, insulin sensitivity, and inflammatory processes. Emerging data suggest that antioxidants may improve endothelial function, reduce blood pressure, and enhance metabolic homeostasis in obese children. However, the long-term efficacy and safety of antioxidant supplementation remain uncertain, necessitating further rigorous randomized controlled trials. A deeper understanding of antioxidants' role in pediatric obesity could unlock novel therapeutic approaches for managing obesity-related complications and improving children's overall health outcomes.

Association between serum ferritin level and lipid profile among diabetic patients: A retrospective cohort study

High serum ferritin (SF) levels have been linked to obesity, metabolic syndrome, atherosclerosis, diabetes, dyslipidemia, and cancer. This study aimed to investigate the association between SF and dyslipidemia in adults diagnosed with diabetes mellitus. This cross-sectional study retrospectively analyzed the electronic medical records of eligible patients from 3 primary locations in Saudi Arabia namely - Abha, Khamis Mushyt, and Jeddah - from 2010 to 2020. The study included adult patients aged 18 years or older who were diagnosed with diabetes mellitus and identified with an HbA1c level of ≥6.5. This study involved 3674 participants, with males accounting for 26.6% of the total. The mean age of the studied population was 48.0 ± 18.4 years. The median [interquartile range] of SF among males was higher than females, however, this difference was not statistically significant (60.0 [23.4-125.8] vs 55.4 [24.0-113.4], P = 0.204). On the other hand, age and region were significantly associated with SF (P = .032 and 0.035). SF had a significant positive correlation with cholesterol (r = 0.081, P < .001), low-density lipoprotein cholesterol (r = .087, P < .001), and triglycerides (r = 0.068, P < .001) and negative correlation with high-density lipoprotein cholesterol (r = -0.13, P < .001). Multivariate analysis revealed that age, sex, residence, and HbA1c were significantly affecting the lipid profile. Clinicians should consider including SF testing as part of the comprehensive evaluation of patients with diabetes and dyslipidemia.

Childhood Obesity and Essential Micronutrients: Insights from India's Comprehensive National Nutrition Survey (2016-18)

INTRODUCTION

Based on the long-term impact of childhood obesity, there is a compelling need to assess the burden of obesity and micronutrient deficiency and the interactions between the two. Thus, the aims of the study were to estimate the prevalence of overweight and obese children and adolescents to compare micro-nutrient levels in these children with normal and underweight categories and explore the factors affecting overweight and obesity in the presence of micronutrient deficiencies.

METHODS

Secondary data analysis of the Comprehensive National Nutrition Survey-India (2017-2018) was done. The survey recorded information from 112,245 preschool children (6-60 months), school age children (5-9 years), and adolescents (10-19 years). Half of these participants were invited for biochemical testing and were included in our analysis. The presence of overweight or obesity and micronutrient (serum erythrocyte folate; vitamin B12, A, and D; ferritin; zinc; and urinary iodine) deficiencies were the primary outcomes. The secondary outcome included the mean serum levels and predictors of overweight and obesity in the presence of micronutrient deficiencies.

RESULTS

Of the 38,060, 38,355, and 35,830 preschool, school-age, and adolescent study participants, about 2.69, 4.18, and 4.99% were overweight or obese. We observed significant variations in the mean folate and vitamin B12 levels among the overweight and obese preschool and school-age children compared to the normal weight group. School-age children exhibited significant differences in all micronutrient levels. In contrast, adolescents only showed substantial differences in vitamin D and A and serum ferritin levels. The predictors of overweight and obesity included geographical locations, wealth quintiles, and societal castes. Iron, folate, vitamin D, and zinc levels significantly affect the odds of developing childhood overweight and obesity.

CONCLUSIONS

It is vital to halt the growing burden of childhood overweight and obesity. Addressing micronutrient deficiencies can help us bring a sustainable and feasible approach to managing this menace.

Iron status and cardiometabolic risk in children

AIM

We aimed to evaluate associations between serum ferritin and transferrin and variables related to the metabolic syndrome (MetS) in children.

METHODS

Cross-sectional and longitudinal study in prepubertal children(n=832) aged 3-14 years. A subset(n=203) were re-examined after a mean follow-up of 3.7±0.8 years[range 2-6]. Outcomes were MetS and MetS components scores, glycosylated haemoglobin (HbA1c), and their follow-up change.

RESULTS

Children with low ferritin had increased HbA1c Z scores (ANCOVA,P=0.003). Ferritin was inversely associated with glycaemia [fully adjusted β (95% confidence interval): -2.35(-4.36 to -0.34)]. Transferrin was associated with diastolic blood pressure[β: 0.02(0.01-0.04)] and log-HOMA-IR [β:0.001(0.0005-0.002)]. MetS risk score worsened during follow-up in children with the lowest baseline ferritin levels. In contrast, at baseline ferritin was positively associated with all (except glycaemia) the MetS-related variables but adjustments for inflammatory, hepatic function, and body mass markers attenuated those associations(P>0.05).

CONCLUSIONS

Lower iron status was independently associated with glycaemic markers and MetS in children, whereas higher ferritin levels were related to other cardiometabolic risk markers under the influence of inflammation, hepatic injury and body mass. Research is required to study whether this mixed pattern is part of an early risk or would be explained by a normal transition during growth and development.

Exposure to a static magnetic field attenuates hepatic damage and function abnormality in obese and diabetic mice

Static magnetic fields (SMFs) exhibit significant effect on health care. However, the effect of SMF on hepatic metabolism and function in obesity and diabetes are still unknown. Liver is not only the main site for glucolipid metabolism but also the core part for iron metabolism regulation. Dysregulations of iron metabolism and redox status are risk factors for the development of hepatic injury and affect glucolipid metabolism in obesity and diabetes. Mice of HFD-induced obesity and HFD/streptozocin-induced diabetes were exposed to a moderate-intensity SMF (0.4-0.7 T, direction: upward, 4 h/day, 8 weeks). Results showed that SMF attenuated hepatic damage by decreasing inflammation and fibrosis in obese and diabetic mice. SMF had no effects on improving glucose/insulin tolerance but regulated proteins (GLUT1 and GLUT4) and genes (G6pc, Pdk4, Gys2 and Pkl) participating in glucose metabolism with phosphorylation of Akt/AMPK/GSK3β. SMF also reduced lipid droplets accumulation through decreasing Plin2 and Plin5 and regulated lipid metabolism with elevated hepatic expressions of PPARγ and C/EBPα in obese mice. In addition, SMF decreased hepatic iron deposition with lower FTH1 expression and modulated systematic iron homeostasis via BMP6-mediated regulation of hepcidin. Moreover, SMF balanced hepatic redox status with regulation on mitochondrial function and MAPKs/Nrf2/HO-1 pathway. Finally, we found that SMF activated hepatic autophagy and enhanced lipophagy by upregulating PNPLA2 expression in obese and diabetic mice. Our results demonstrated that SMF significantly ameliorated the development of hepatic injury in obese and diabetic mice by inhibiting inflammatory level, improving glycolipid metabolism, regulating iron metabolism, balancing redox level and activating autophagy.

Relationship between Serum Ferritin Level and Dyslipidemia in US Adults Based on Data from the National Health and Nutrition Examination Surveys 2017 to 2020

Previous research has suggested that high serum ferritin (SF) levels may be associated with dyslipidemia. This study investigated the association between SF levels and dyslipidemia in American adults, which held relevance for both clinical and public health areas concerned with screening and prevention. Data from the pre-pandemic National Health and Nutrition Examination Surveys (NHANES), conducted between 2017 and 2020, were utilized for this analysis. Multivariate linear regression models were used to explore the correlation between lipid and SF concentrations, and the connection between SF and the four types of dyslipidemia was further assessed by using multivariate logistic regression analysis. Odds ratios (ORs; 95% CI) for dyslipidemia were calculated for quartiles of SF concentrations, with the lowest ferritin quartile as the reference. The final subjects consisted of 2676 participants (1290 males and 1386 females). ORs for dyslipidemia were the highest in the fourth quartile (Q4) of SF both in males (OR: 1.60, 95% CI: 1.12-2.28) and females (OR: 1.52, 95% CI: 1.07-2.17). The crude ORs (95% CI) for the risk of High TC and High LDL-C increased progressively in both genders. However, after adjusting for covariates, the trend of significance was only present in females. Finally, the association between total daily iron intake and the four types of dyslipidemia was examined, revealing that the risk of High TG in the third quartile of the total daily iron intake was 2.16 times greater in females (adjusted OR: 3.16, 95% CI: 1.38-7.23). SF concentrations were remarkably associated with dyslipidemia. In females, daily dietary iron intake was associated with High-TG dyslipidemia.

Maternal iron status in early pregnancy and childhood body fat measures and cardiometabolic risk factors: A population-based prospective cohort

BACKGROUND

Whether maternal iron status during pregnancy is associated with cardiometabolic health in the offspring is poorly known.

OBJECTIVES

We aimed to assess the associations of maternal iron status during early pregnancy with body fat measures and cardiometabolic risk factors in children aged 10 y.

METHODS

In a population-based cohort study among 3718 mother-child pairs, we measured ferritin, transferrin, and transferrin saturation during early pregnancy. We obtained child BMI, fat mass index, and android/gynoid fat mass ratio by DXA, subcutaneous fat index, visceral fat index, pericardial fat index, and liver fat fraction by magnetic resonance imaging and assessed systolic and diastolic blood pressure, serum lipids, glucose, insulin, and CRP at 10 y.

RESULTS

A one-standard deviation score (SDS) higher maternal ferritin was associated with lower fat mass index [difference -0.05 (95% CI: -0.08, -0.02) SDS] and subcutaneous fat index [difference -0.06 (95% CI: -0.10, -0.02) SDS] in children. One-SDS higher maternal transferrin was associated with higher fat mass index [difference 0.04 (95% CI: 0.01, 0.07) SDS], android/gynoid fat mass ratio [difference 0.05 (95% CI: 0.02, 0.08) SDS], and subcutaneous fat index [difference 0.06 (95% CI: 0.02, 0.10) SDS] in children. Iron status during pregnancy was not consistently associated with organ fat and cardiometabolic risk factors at 10 y.

CONCLUSIONS

Maternal lower ferritin and higher transferrin in early pregnancy are associated with body fat accumulation and distribution but are not associated with cardiometabolic risk factors in childhood. Underlying mechanisms and long-term consequences warrant further study.

Obesity, putative biological mediators, and cognitive function in a national sample of children and adolescents

Childhood obesity has reached epidemic rates nationwide and may be associated with impaired cognitive function. A growing body of evidence suggests that poorer academic performance for children with obesity and overweight is related to declines in executive function skills. This study aimed to identify biological mediators between obesity and overweight and cognitive function among children and adolescents. A total of 3323 children aged 6-16 years from the Third National Health and Nutrition Examination Survey between 1988 and 1994 (NHANES III) was used to measure associations between measures of obesity and overweight, cognitive function (IQ test batteries), iron deficiency, inflammation (c-reactive protein), and glucose metabolism (glycosylated hemoglobin) using multiple mediation models. Approximately 15% of the children were overweight and 11% were obese. Results showed lower scores for children who were obese or overweight than children of normal weight on several IQ subtest batteries. Obesity and overweight were also associated with biological mediators such as iron deficiency, elevated c-reactive protein and glycosylated hemoglobin. Several biomarkers of iron status were also related to measures of cognitive function. Early declines in cognitive function are associated with biomarkers of iron deficiency and inflammation in children and adolescents, and while some biological linkages between obesity and overweight and cognitive function are identified herein, further study is needed to identify additional biological mediators between obesity and overweight and cognitive function in pediatric populations.

Association of Iron Storage Markers with Metabolic Syndrome and Its Components in Chinese Rural 6-12 Years Old Children: The 2010-2012 China National Nutrition and Health Survey

Background: Elevated ferritin, which is often used to represent iron storage, is known to increase the risk of metabolic syndrome (MetS) or its components, but its increase is affected by many factors. Therefore, it is necessary to analyze the relationship between other indicators of iron storage, and MetS and its components in order to fully understand the role of iron in the occurrence and development of these diseases. Although there are many studies to analyze the relationship involved in adults and adolescents, in children there is limited research. In this study, we aim to estimate the association of whole blood iron, ferritin, and total body iron with metabolic syndrome, and especially its components in Chinese rural children aged 6–12 years old. Method: A total of 1333 children aged 6–12 years old were enrolled from the 2010–2012 China National Nutrition and Health Survey in this study. Markers of iron storage (whole blood iron, ferritin, and total body iron (TBI)) and MetS component parameters (waist, blood pressure, high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), and fast glycose) were collected. A multivariate logistic regression analysis was performed to confirm the independent relationship between iron storage markers, and the incident of metabolic syndrome and its components. Results: After adjusting for age, gender, C-reactive protein (CRP), and body mass index (BMI), a negative association was found between whole blood iron, ferritin, and TBI and incidence of reduced HDL-C (odds ratio (OR) = 0.63, 0.49, and 0.57, respectively). The highest tertile of whole blood iron increased the risk of the incidence of hyperglycemia (OR = 1.74), while TBI decreased the risk by 61%. No significant association was found between ferritin tertiles and the incidence of hyperglycemia. Conclusion: An iron storage level within the normal range in children is associated with a risk of MetS components, especially in hyperglycemia and reduced HDL-C. The relationship between the three iron indexes and metabolic syndrome and its components is not completely consistent, which suggests that the underlying mechanism is complex and needs to be further explored.

Ferritin levels throughout childhood and metabolic syndrome in adolescent stage

BACKGROUND AND AIM

Increased ferritin levels have been widely associated with cardiovascular risk in adults. Whether ferritin levels and their changes during childhood are related to metabolic syndrome (MetS) at adolescence is unknown. We aimed to evaluate these associations using levels of ferritin at 5, 10 and 16 years and their linear increases and patterns of sustained increased levels across childhood.

METHODS AND RESULTS

There were four samples evaluated according to non-missing values for study variables at each stage (5 years: 562; 10 years: 381; and 16 years: 567 children; non-missing values at any stage: 379). MetS risk was evaluated as a continuous Z score. Patterns of sustained increased ferritin (highest tertile) and slope of the change of ferritin per year across the follow-up were calculated. Ferritin levels in the highest versus lowest tertile at five and 16 years were significantly positively associated with MetS risk Z score at adolescence in boys and these associations were unaffected by adjustment for covariates. Having high, compared to low/moderate ferritin level at 2 or more time periods between 5 and 16 years was related to higher Mets Z-score in boys only [e.g. 5-10 years adjusted-beta (95 %CI):0.26 (0.05-0.48),P < 0.05]. In girls, ferritin Z score at 10 and 16 years was positively and independently associated with HOMA-IR Z score. In girls, the slope of ferritin per year in the highest tertile was positively associated with MetS risk Z-score [adjusted-beta (95 %CI):0.21 (0.05-0.38),P < 0.05].

CONCLUSIONS

Ferritin levels throughout childhood are positively related to cardiometabolic risk in adolescence, with associations varying by sex.

Iron metabolism and its association with dyslipidemia risk in children and adolescents: a cross-sectional study

Background

Information on the association between iron metabolism and dyslipidaemia in children is limited. Thus, this study aims to evaluate the iron metabolic status of children with different body mass index (BMI) and to examine the association between iron metabolism and dyslipidaemia risk.

Method

In total, 1866 children and adolescents aged 7–18 were enrolled in this study, including 912 boys and 954 girls. In this cross-sectional study, parameters for anthropometry, lipids and iron metabolism including transferrin, soluble transferrin receptor (sTfR), ferritin and serum iron (SF) were evaluated. Data regarding demographic characteristics, diet, and physical activity were collected by self-reported questionnaires.

Results

The prevalence of dyslipidaemia and iron deficiency in children and adolescents increased based on BMI categories (both P < 0.05) and were 58.3 and 8.9% in subjects with obesity, respectively. The lowest SF and the highest ferritin levels were observed in subjects who were obese (both P < 0.001). Subjects with dyslipidaemia had lower SF, transferrin and sTfR levels by different BMI categories, and those who were obese had higher ferritin levels (all P < 0.05). Most importantly, higher concentrations of transferrin and sTfR were related to lower dyslipidaemia risk (OR for transferrin: 0.49, 95% CI: 0.33–0.71; OR for sTfR: 0.68, 95% CI: 0.46–0.99).

Conclusions

A downward trend in SF level by BMI categories and the highest ferritin level in subjects with obesity suggested that iron storage was associated with BMI in children and adolescents. Moreover, an inverse relationship was observed between transferrin and sTfR concentrations and dyslipidaemia risk in children with different BMI.

Effect of Daily Iron Supplementation in Healthy Exclusively Breastfed Infants: A Systematic Review with Meta-Analysis

BACKGROUND

The literature on the iron requirements of exclusively breastfed infants contains conflicting data and contrary views.

OBJECTIVE

The purpose of this study was to summarize the evidence for both benefits and risks of daily oral iron supplementation with regard to hematologic, growth, cognitive parameters, and adverse effects in exclusively breastfed infants.

MATERIALS AND METHODS

Structured electronic searches were conducted using PubMed, Cochrane Library databases, and Google Scholar for randomized controlled trials (RCTs) involving daily iron supplementation in full-term healthy exclusively breastfed infants. Random- and fixed-effects models were used for calculating the pooled estimates.

RESULTS

Four RCTs with 511 infants were included in the meta-analysis. Iron interventions had no significant effect on iron deficiency or iron deficiency anemia, serum ferritin level, or hemoglobin level. Iron interventions did result in a significant increase in Bayley psychomotor developmental indices in later life (mean difference [MD] = 7.00, confidence interval [95% CI] 0.99-13.01) and mean corpuscular volume (MD = 2.17 fL; 95% CI 0.99-3.35 fL). Iron supplementation was associated with slower growth during the exclusive breastfeeding period, but the long-term effect is unclear.

CONCLUSIONS

Limited available evidence suggests that daily iron supplementation has beneficial effects on hematologic parameters and cognitive development, but may delay physical growth in healthy exclusively breastfed infants. There was no evidence to suggest that iron supplementation could cause other adverse effects.

A review of iron studies in overweight and obese children and adolescents: a double burden in the young?

INTRODUCTION

The connection between iron and excessive adiposity has received much research interest. Although children and adolescents have unique developmental phases and nutritional demands, to date, reviews of iron in the overweight (OW) and obese (OB) have combined studies of children and adults or have focussed on adults.

PURPOSE

The aim of this review was to critically evaluate studies of the relationship between iron and OW and obesity in children and adolescents, with emphasis on iron status, oral iron response, dietary intake and systemic inflammatory markers.

METHODS

A PubMed search was conducted to identify relevant articles published up to December 2015. Combinations of the following keywords were used: iron, OW, OB, children, adolescents, diet, hepcidin, inflammation, fortification, supplementation, weight loss, trace elements, obesity, iron deficiency (ID), minerals.

RESULTS AND CONCLUSION

A higher prevalence of ID, or risk of ID, among OW and OB children and adolescents has been consistently observed. Chronic inflammation caused by excessive adiposity offers a plausible explanation for this finding, rather than dietary factors. However, future studies must employ screening for the presence of both acute and chronic infections and inflammatory conditions and report other factors such as pubertal status. Intervention studies, although few, indicate that OW and OB children and adolescents have reduced response to oral iron. Further trials are needed to explore the connection between body fat mass, inflammatory proteins and iron absorption, together with the effect of weight loss on iron status in iron-deficient OW and OB children and adolescents.

Iron Metabolism Dysregulation and Cognitive Dysfunction in Pediatric Obesity: Is There a Connection?

Obesity and iron deficiency (ID) are two of the most common nutritional disorders in the world. In children both conditions deserve particular attention. Several studies revealed an association between obesity and iron deficiency in children and, in some cases, a reduced response to oral supplementation. The connecting mechanism, however, is not completely known. This review is focused on: (1) iron deficiency in obese children and the role of hepcidin in the connection between body fat and poor iron status; (2) iron status and consequences on health, in particular on cognitive function; (3) cognitive function and obesity; (4) suggestion of a possible link between cognitive dysfunction and ID in pediatric obesity; and implications for therapy and future research.