The role of blood loss and diet in the aetiology of mild iron deficiency in premenopausal adult New Zealand women

Socio-Demographic Determinant Factors for Serum Iron, Copper, Zinc, and Selenium Concentrations Among U.S. Women of Childbearing Age

BACKGROUND

Trace elements (TEs) are essential nutrients for the human body and have a significant impact on fertility and hormone levels in women of reproductive age, underscoring the importance of understanding sociodemographic variations in their concentrations within this population.

OBJECTIVE

To investigate the socio-demographic factors influencing blood concentrations of four essential TEs, including iron, zinc, copper, and selenium among women of reproductive age.

METHODS

A cross-sectional analysis of women aged 20-44 years was performed using the National Health and Nutrition Examination Survey, 1999-2018. Serum iron data were analyzed for 9211 women across 10 cycles, while serum copper, zinc, and selenium data were available for 1027 women across 3 cycles. Generalized linear and logistic regressions examined the individual associations of socio-demographic factors, including age, race and ethnicity, education, and poverty index ratio, with iron, zinc, copper, and selenium concentrations treated as continuous and categorical outcomes, respectively. A qualitative heatmap explored the joint associations between the socio-demographic factors and the four essential TEs.

RESULTS

Reduced iron concentrations and increased risks of insufficiency occurred in older, Black, low-education, or low-income women. Black women were more likely to have lower zinc and selenium concentrations and an increased risk of zinc insufficiency but higher copper concentrations. The qualitative heatmap found that older, Black, low-education, and low-income women generally had lower concentrations of the four TEs, particularly iron (β = -0.10; p < 0.01).

CONCLUSIONS

Socially disadvantaged women are more likely to present with lower TE concentrations, and these specific population groups should be targeted by replenishment planning by public health initiatives.

Menstrual blood loss is an independent determinant of hemoglobin and ferritin levels in premenopausal blood donors

INTRODUCTION

To prevent blood donors from developing iron deficiency (ferritin <15 μg/L) and subsequent anemia (hemoglobin <120 g/L), blood services rely on information about known risk factors, including the donor's sex and age. For example, while Finnish women are able to donate whole blood with a minimum donation interval of 91 days, women in the 18 to 25-year-old age group are recommended to donate no more than once per year. Menstrual blood loss is not accounted for in blood donation interval recommendations, despite being a known risk factor of iron deficiency. We aim to investigate to what extent menstrual bleeding is associated with ferritin and hemoglobin levels in female blood donors, and quantify the association of other menstruation-related variables not currently accounted for by blood services (i.e., use of hormonal contraception, heavy menstrual bleeding) with iron deficiency or anemia.

MATERIAL AND METHODS

The study population consisted of 473 premenopausal and 491 postmenopausal Dutch whole blood donors. Exclusion criteria were current pregnancy, BMI ≥50, ferritin ≥200, pictorial blood assessment chart (PBAC) ≥400, and age <18 or ≥70 years. Menstrual blood loss was quantified using a PBAC, a semiquantitative method to evaluate the number of used menstrual products and the degree of staining. We identified predictors of log(ferritin)/hemoglobin and iron deficiency/anemia using Bayesian linear and logistic regression models and quantified the average percentage of variance in log(ferritin) and hemoglobin explained by the covariates.

RESULTS

Menstrual blood loss accounted for most of the explained variance in hemoglobin (8%) and second only to the number of days since last donation for ferritin (8%). Heavy menstrual bleeding (PBAC ≥150, OR = 3.56 [1.45-8.85], prevalence 13%) was associated with anemia, and use of levonorgestrel-releasing intrauterine device was negatively associated with iron deficiency (OR = 0.06 [0.01-0.44]). After statistical control for menstrual blood loss, age was not associated with iron status.

CONCLUSIONS

Menstrual blood loss and blood donation were the most important determinants of iron status in premenopausal women. Thus, results suggest that accounting for menstrual blood loss in donation interval guidelines may benefit blood donors.

Body Fat Percentage and Blood Donation are the Strongest Determinants of Iron Stores in Premenopausal Women Joining the New Zealand Army

INTRODUCTION

Suboptimal iron status is an issue for women joining the military because of its association with impaired aerobic performance, yet no studies have investigated dietary and non-dietary determinants of iron status simultaneously in this population. The purpose of this study was to explore associations between iron stores, dietary patterns (DPs), and potential non-dietary determinants of iron status in premenopausal women at the commencement of basic military training (BMT) in the New Zealand Army.

METHODS

During week 1 of BMT, demographic, body composition, lifestyle, medical history, and dietary data were measured as potential determinants of serum ferritin (SF) in 101 participants. Following univariate analysis, age, body fat percentage, previous blood donation, at least 6 h of exercise per week that raised the heart rate, and a vegetarian DP were analyzed using a multiple linear regression model.

RESULTS

An increase in body fat percentage was associated with increased SF (P < .009), although blood donation in the past year decreased SF (P < .011) compared to those participants who did not donate blood. There was no association between SF and a vegetarian DP or hours of exercise per week. The model explained 17.5% of the variance in SF at the commencement of BMT.

CONCLUSION

Body fat percentage and blood donation in the past year were the strongest determinants of iron stores in healthy premenopausal women commencing BMT. It is recommended that women joining the New Zealand Army are provided information to maintain or improve their iron status based on these findings. This includes clinical screening of iron status, advice for women considering blood donation, and dietary advice regarding total energy requirements and iron bioavailability.

Menstrual cycle affects iron homeostasis and hepcidin following interval running exercise in endurance-trained women

PURPOSE

Menstrual cycle phase affects resting hepcidin levels, but such effects on the hepcidin response to exercise are still unclear. Thus, we investigated the hepcidin response to running during three different menstrual cycle phases.

METHODS

Twenty-one endurance-trained eumenorrheic women performed three identical interval running protocols during the early-follicular phase (EFP), late-follicular phase (LFP), and mid-luteal phase (MLP). The protocol consisted of 8 × 3 min bouts at 85% of the maximal aerobic speed, with 90-s recovery. Blood samples were collected pre-exercise and at 0 h, 3 h and 24 h post-exercise.

RESULTS

Data presented as mean ± SD. Ferritin were lower in the EFP than the LFP (34.82 ± 16.44 vs 40.90 ± 23.91 ng/ml, p = 0.003), while iron and transferrin saturation were lower during the EFP (58.04 ± 19.70 µg/dl, 14.71 ± 5.47%) compared to the LFP (88.67 ± 36.38 µg/dl, 22.22 ± 9.54%; p < 0.001) and the MLP (80.20 ± 42.05 µg/dl, 19.87 ± 10.37%; p = 0.024 and p = 0.045, respectively). Hepcidin was not affected by menstrual cycle (p = 0.052) or menstrual cycle*time interaction (p = 0.075). However, when comparing hepcidin at 3 h post-exercise, a moderate and meaningful effect size showed that hepcidin was higher in the LFP compared to the EFP (3.01 ± 4.16 vs 1.26 ± 1.25 nMol/l; d = 0.57, CI = 0.07-1.08). No effect of time on hepcidin during the EFP was found either (p = 0.426).

CONCLUSION

The decrease in iron, ferritin and TSAT levels during the EFP may mislead the determination of iron status in eumenorrheic athletes. However, although the hepcidin response to exercise appears to be reduced in the EFP, it shows no clear differences between the phases of the menstrual cycle (clinicaltrials.gov: NCT04458662).

Obese Vegetarians and Omnivores Show Different Metabolic Changes: Analysis of 1340 Individuals

Our study evaluated the association between the increase in body mass index (BMI) in men and women (menstruating and non-menstruating) (n = 1340) with different dietary groups (omnivores, semi-vegetarians, lacto-ovo-vegetarian, and vegans) and the measurement of the biochemical markers high-sensitive C-reactive protein (hs-CRP), ferritin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), glycated hemoglobin (HbA1C), and insulin resistance index (HOMA-IR). Increasing BMI values in all groups and dietary profiles were related to a significant increase in hs-CRP (p < 0.0001), ALT (p = 0.02), ferritin (p = 0.009), and HbA1C (p < 0.0001), with no difference between dietary groups (p < 0.05). The increase in BMI increases the levels of HOMA-IR (p < 0.0001) and GGT (p < 0.05), with higher values found in men when compared to women (p < 0.0001 for HOMA- IR and p = 0.0048 for GGT). The association between ALT and BMI was different between dietary groups, as it showed a decrease in vegan women who do not menstruate compared to other dietary groups (p = 0.0099). When including only obese individuals (BMI ≥ 30 kg/m2, n = 153) in the analysis, we observed lower concentrations of GGT and ferritin in vegetarians than in omnivores, regardless of gender and menstrual blood loss (p = 0.0395). Our data showed that for both vegetarians and omnivores, the higher the BMI, the worse the metabolic parameters. However, regarding obesity, vegetarians showed better antioxidant status (lower GGT elevation) and lower inflammatory status (lower ferritin elevation), which may provide them with potential protection in the development of morbidities associated with overweight.

Prevalence of thyroid dysfunction in postpartum women with suboptimal iodine and selenium and adequate iron status

OBJECTIVE

Postpartum women experience thyroid dysfunction at twice the prevalence of the general population. Adequate biosynthesis of thyroid hormones depends on three trace elements: iodine, selenium and iron. This study aimed to investigate thyroid dysfunction within a cohort of women at six months postpartum in relation to iodine, selenium and iron status.

DESIGN

This cross-sectional study was part of an observational longitudinal cohort Mother and Infant Nutrition Investigation; data obtained at six months postpartum are reported.

SUBJECTS

Mother-infant pairs (n = 87) were recruited at three months postpartum and followed up at six months postpartum (n = 78).

MEASUREMENTS

Thyroid hormones (free triiodothyronine, free thyroxine, thyroid-stimulating hormone) and thyroid peroxidase antibodies were measured. Urinary iodine concentration, breast milk iodine concentration, serum thyroglobulin, plasma selenium, serum ferritin and serum soluble transferrin receptors were determined. Nonparametric data were expressed as median (25th, 75th percentile).

RESULTS

Thyroid dysfunction was found in 18% of women, and 4% of women had iron deficiency. Median urinary iodine concentration was 85 (43, 134) µg/L, median breast milk iodine concentration was 59 (39, 109) µg/L, and median serum thyroglobulin at 11.4 (8.6, 18.6) µg/L, indicating iodine deficiency. Median plasma selenium concentration was 105.8 (95.6, 115.3) µg/L. Women with marginally lower plasma selenium concentration were 1.12% times more likely to have abnormal TSH concentrations (p = .001).

CONCLUSIONS

There was a high prevalence of thyroid dysfunction. Plasma selenium concentration was the only significant predictor of the likelihood that women had thyroid dysfunction within this cohort, who were iodine deficient and mostly had adequate iron status. Strategies are required to improve both iodine and selenium status to better support maternal thyroid function.

Iron status in athletic females, a shift in perspective on an old paradigm

Iron deficiency is a common nutrient deficiency within athletes, with sport scientists and medical professionals recognizing that athletes require regular monitoring of their iron status during intense training periods. Revised considerations for athlete iron screening and monitoring have suggested that males get screened biannually during heavy training periods and females require screening biannually or quarterly, depending on their previous history of iron deficiency. The prevalence of iron deficiency in female athletes is higher than their male counterparts and is often cited as being a result of the presence of a menstrual cycle in the premenopausal years. This review has sought to revise our current understanding of female physiology and the interaction between primary reproductive hormones (oestrogen and progesterone) and iron homoeostasis in females. The review highlights an apparent symbiotic relationship between iron metabolism and the menstrual cycle that requires additional research as well as identifying areas of the menstrual cycle that may be primed for nutritional iron supplementation.

Multi-element Analysis of Brain Regions from South African Cadavers

Trace elements are vital for a variety of functions in the brain. However, an imbalance can result in oxidative stress. It is important to ascertain the normal levels in different brain regions, as such information is still lacking. Therefore, this study aimed to provide baseline trace element concentrations from a South African population, as well as determine trace element differences between sex and brain regions. Samples from the caudate nucleus, putamen, globus pallidus and hippocampus were analysed using inductively coupled plasma mass spectrometry. Aluminium, antimony, arsenic, barium, boron, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, mercury, molybdenum, nickel, phosphorus, potassium, selenium, silicon, sodium, strontium, vanadium and zinc were assessed. A multiple median regression model was used to determine differences between sex and regions. Twenty-nine male and 13 female cadavers from a Western Cape, South African population were included (mean age 35 years, range 19 to 45). Trace element levels were comparable to those of other populations, although magnesium was considerably lower. While there were no sex differences, significant anatomical regional differences existed; the caudate nucleus and hippocampus were the most similar, and the globus pallidus and hippocampus the most different. In conclusion, this is the first article to report the trace element concentrations of brain regions from a South African population. Low magnesium levels in the brain may be linked to a dietary deficiency, and migraines, depression and epilepsy have been linked to low magnesium levels. Future research should be directed to increase the dietary intake of magnesium.

Hepcidin and iron: novel findings for elite female rugby Sevens players

BACKGROUND

Iron deficiency is a common deficiency disease worldwide with athletes at increased risk.

METHODS

A proposed new mechanism of exercise-induced iron deficiency in athletes involves the iron-regulatory hormone hepcidin, however, there is limited information on this amongst elite athletes. This study describes iron status in elite female rugby Sevens players.

RESULTS

Blood samples were collected at the start and mid-season and analyzed for serum iron, serum ferritin (SF), soluble transferring receptor (sTfR), high sensitivity C-reactive Protein (hsCRP) and hepcidin. Of the 17 players 18% were iron deficient (SF<30 µg/L) with 29-35% of players with sub-optimal iron stores at some point during the study (SF<45 µg/L). Serum hepcidin was strongly correlated with SF (r=0.61, P=0.0001).

CONCLUSIONS

Some elite female rugby Sevens players have sub-optimal iron stores over the course of a season.

Iron insufficiency among young Australian women: a population-based survey

BACKGROUND

Although serum ferritin is considered a reliable indicator of iron stores, there are few data documenting the prevalence of low ferritin in representative samples of young women.

AIMS

To estimate the prevalence of low ferritin and to identify factors associated with low ferritin in young Australian women.

METHODS

Women, aged 18-39 years, living in the eastern states of Australia were recruited by email to a cross-sectional, online questionnaire-based study between November 2016 and July 2017. Participants not pregnant, breast feeding, taking hormonal contraception, using assisted reproduction or postmenopausal were invited to provide a blood sample.

RESULTS

Of the 3689 invited participants, 761 (23.1%) provided a sample and 736 women, mean (SD) age 31.7 (±5.6) years, were included in the analyses. The overall prevalence of serum ferritin <30 μg/L was 34.8% (95% confidence interval (CI) 31.4-38.3%), with 41.4% (35.1-48.0%) in NSW, 31.5% (26.4-37.1%) in Victoria and 32.6% (26.8-39.0%) in Queensland. Serum ferritin <30 μg/L was positively associated with the reporting of >2 days of heavy menstrual bleeding (adjusted odds ratio (AOR) 1.73, 95% CI 1.15-2.59), living in New South Wales (AOR 1.57, 95% CI 1.07-2.30), not working outside home (AOR 1.58, 95% CI 1.01-2.49), and inversely associated with never experiencing heavy menses (AOR 0.46, 95% CI 0.23-0.93) and obesity (AOR 0.32, 95% CI 0.21-0.50).

CONCLUSIONS

This study demonstrates that serum ferritin below 30 μg/L is common amongst young Australian women. Healthcare professionals should note the association between low ferritin and heavy bleeding.

Iron status and associations with physical performance during basic combat training in female New Zealand Army recruits

Decreases in Fe status have been reported in military women during initial training periods of 8-10 weeks. The present study aimed to characterise Fe status and associations with physical performance in female New Zealand Army recruits during a 16-week basic combat training (BCT) course. Fe status indicators - Hb, serum ferritin (sFer), soluble transferrin receptor (sTfR), transferrin saturation (TS) and erythrocyte distribution width (RDW) - were assessed at the beginning (baseline) and end of BCT in seventy-six volunteers without Fe-deficiency non-anaemia (sFer 10 mg/l at baseline or end. A timed 2·4 km run followed by maximum press-ups were performed at baseline and midpoint (week 8) to assess physical performance. Changes in Fe status were investigated using paired t tests and associations between Fe status and physical performance evaluated using Pearson correlation coefficients. sFer (56·6 (sd 33·7) v. 38·4 (sd 23·8) µg/l) and TS (38·8 (sd 13·9) v. 34·4 (sd 11·5) %) decreased (P&lt;0·001 and P=0·014, respectively), while sTfR (1·21 (sd 0·27) v. 1·39 (sd 0·35) mg/l) and RDW (12·8 (sd 0·6) v. 13·2 (sd 0·7) %) increased (P&lt;0·001) from baseline to end. Hb (140·6 (sd 7·5) v. 142·9 (sd 7·9) g/l) increased (P=0·009) during BCT. At end, sTfR was positively (r 0·29, P=0·012) and TS inversely associated (r -0·32, P=0·005) with midpoint run time. There were no significant correlations between Fe status and press-ups. Storage and functional Fe parameters indicated a decline in Fe status in female recruits during BCT. Correlations between tissue-Fe indicators and run times suggest impaired aerobic fitness. Optimal Fe status appears paramount for enabling success in female recruits during military training.

Iron status at opposite ends of the menstrual function spectrum

OBJECTIVES

Although exercising women are at high risk of poor iron status, it is unknown how non-pathological, physiological menstrual function affects iron status. As such, this study investigates the association between menstrual function and iron status in exercising women with amenorrhea and exercising women with ovulatory, eumenorrheic menstrual cycles.

DESIGN

Cross-sectional analysis of iron depletion prevalence, iron status indices, exercise parameters, and diet composition.

METHODS

Women aged 18-35 years performing at least 2 h per week of aerobic exercise were recruited. Women with amenorrhea (AMEN) were defined by the absence of menses for at least 90 days or less than 6 menses in the past 12 months (n = 82). Women with ovulatory, eumenorrheic menstrual cycles (OvEU) were defined by the presence of ovulatory cycles of 26-35 days in length for the past 6 months (n = 109). Group differences in serum ferritin (Ft), soluble transferrin receptor (sTfR), total body iron (TBI), hemoglobin (Hb), hematocrit (Hct), iron depletion prevalence (Ft <15 μg/L), peak oxygen consumption (VO_2peak), exercise minutes per week, and diet logs were assessed.

RESULTS

The prevalence of iron depletion was greater in OvEU when compared to AMEN (26% vs. 15%, p = 0.04). No significant differences were observed between AMEN and OvEU in Ft (30.2 ± 2.2 vs. 24.9 ± 2.6 μg/L; p = 0.62), sTfR (5.2 ± 1.4 vs. 4.9 ± 1.5 mg/L; p = 0.95), TBI (5.3 ± 2.7 vs. 4.8 ± 3.7 mg/kg; p = 0.42), Hb (13.2 ± 0.4 vs. 13.4 ± 0.6 g/dL; p = 0.80), Hct (39.5 ± 0.8% vs. 39.8 ± 4.1%; p = 0.93), or exercise parameters. AMEN consumed more vitamin C than OvEU (269 ± 180 vs. 129 ± 141 mg/day, p < 0.001), but all other dietary factors were similar between AMEN and OvEU.

CONCLUSION

Exercising women with ovulatory, eumenorrheic cycles are at a greater risk of iron depletion than exercising, amenorrheic women. Thus, menstrual function must be considered when screening for poor iron status in exercising women.

The Unexplored Crossroads of the Female Athlete Triad and Iron Deficiency: A Narrative Review

Despite the severity and prevalence of iron deficiency in exercising women, few published reports have explored how iron deficiency interacts with another prevalent and severe condition in exercising women: the 'female athlete triad.' This review aims to describe how iron deficiency may interact with each component of the female athlete triad, that is, energy status, reproductive function, and bone health. The effects of iron deficiency on energy status are discussed in regards to thyroid function, metabolic fuel availability, eating behaviors, and energy expenditure. The interactions between iron deficiency and reproductive function are explored by discussing the potentially impaired fertility and hyperprolactinemia due to iron deficiency and the alterations in iron metabolism due to menstrual blood loss and estrogen exposure. The interaction of iron deficiency with bone health may occur via dysregulation of the growth hormone/insulin-like growth factor-1 axis, hypoxia, and hypothyroidism. Based on these discussions, several future directions for research are presented.

The effect of vegetarian diets on iron status in adults: A systematic review and meta-analysis

BACKGROUND

Vegetarian diets exclude meat, seafood, and products containing these foods. Although the vegetarian lifestyle could lead to a better health status in adults, it may also bear risks for certain nutritional deficiencies. Cross-sectional studies and narrative reviews have shown that the iron status of vegetarians is compromised by the absence of highly bioavailable haem-iron in meatless diets and the inhibiting effect of certain components present in plant foods on non-haem iron bioavailability.

METHODS

The databases Pubmed, Scopus, Embase, and Cochrane CentralRegister of Controlled Trials were searched for studies comparing serum ferritin, as the major laboratory parameter for iron status of adult vegetarians with non-vegetarian control groups. A qualitative review was conducted as well as an inverse-variance random-effects meta-analysis to pool available data. In addition the effect of vegetarian diets according to gender was investigated with a subgroup analysis. The results were validated using a sensitivity analysis.

RESULTS

A total of 27 cross-sectional studies and three interventional studies were selected for the systematic review. The meta-analysis which combined data of 24 cross-sectional studies showed that adult vegetarians have significantly lower serum ferritin levels than their non-vegetarian controls (-29.71 µg/L, 95% CI [-39.69, -19.73], p < 0.01). Inclusion of semi-vegetarian diets did not change the results considerably (-23.27 µg/L, 95% CI [-29.77, -16.76], p < 0.01). The effects were more pronounced in men (-61.88 µg/L, 95% CI [-85.59, -38.17], p < 0.01) than in both premenopausal women (-17.70 μg/L, 95% CI [-29.80, -5.60], p < 0.01) and all women (-13.50 μg/L, 95% CI [-22.96, -4.04], p < 0.01), respectively.

CONCLUSIONS

In conclusion our results showed that vegetarians are more likely to have lower iron stores compared with non-vegetarians. However, since high iron stores are also a risk factor for certain non-communicable diseases, such as type 2 diabetes, it is recommended that not only vegetarians but also non-vegetarians should regularly control their iron status and improve their diet regarding the content and bioavailability of iron by consuming more plants and less meat.

Associations of dietary, lifestyle, and sociodemographic factors with iron status in Chinese adults: a cross-sectional study in the China Health and Nutrition Survey

BACKGROUND

Although a high prevalence of anemia and related disease burden have been documented in China, limited evidence is available on the current population-level iron status and risk factors for iron imbalance.

OBJECTIVE

We explored the associations of dietary, lifestyle, and sociodemographic factors with iron status in Chinese adults.

DESIGN

Our study population consisted of 7672 adults aged 18-65 y from the 2009 China Health and Nutrition Survey. Diet was assessed with the use of 3 consecutive 24-h dietary recalls. Serum ferritin, serum transferrin receptor, and hemoglobin concentrations were measured.

RESULTS

The geometric means ± SDs for ferritin concentrations were 135.9 ± 2.7 ng/mL in men and 42.7 ± 3.1 ng/mL in women. After adjustment for potential risk factors, including high-sensitivity C-reactive protein concentration, the association between age and ferritin concentration was inverse in men (P-trend < 0.001) and positive in women (P-trend < 0.001). We observed a positive association between body mass index (in kg/m²) and ferritin concentration in both men and women (both P-trends < 0.001). Dietary phytate intake was inversely associated with ferritin concentration in men (P-trend = 0.002) but not in women. Red meat consumption was positively associated with ferritin concentration both in men (P-trend = 0.002) and in older women (P-trend = 0.009). Lower intakes of grains and higher intakes of pork and poultry were associated with higher ferritin concentrations (all P-trends ≤ 0.05) in men but not in women. We observed variations in ferritin concentrations across different geographic regions (both P ≤ 0.01).

CONCLUSIONS

Serum ferritin concentrations varied across different sociodemographic, lifestyle, and dietary factors in this Chinese population. A higher intake of red meat was associated with higher ferritin concentrations in men and older women.

Association between predominantly plant-based diets and iron status in Chinese adults: a cross-sectional analysis

Current evidence of the relationship between diets and Fe status is mostly derived from studies in developed countries with Western diets, which may not be translatable to Chinese with a predominantly plant-based diet. We extracted data that were nationally sampled from the 2009 wave of China Health and Nutrition Survey; dietary information was collected using 24-h recalls combined with a food inventory for 3 consecutive days. Blood samples were collected to quantify Fe status, and log-ferritin, transferrin receptor and Hb were used as Fe status indicators. In total, 2905 (1360 males and 1545 females) adults aged 18–50 years were included for multiple linear regression and stratified analyses. The rates of Fe deficiency and Fe-deficiency anaemia were 1·6 and 0·7 % for males and 28·4 and 10·7 % for females, respectively. As red meat and haem Fe consumption differed about fifteen to twenty times throughout the five groups, divided by quintiles of animal protein intake per 4·2 MJ/d, only Fe status as indicated by log-ferritin (P=0·019) and transferrin receptor (P=0·024) concentrations in males was shown to be higher as intakes of animal foods increased. Log-ferritin was positively associated with intakes of red meat (B=0·3 %, P=0·01) and haem Fe (B=12·3 %, P=0·010) in males and with intake of non-haem Fe in females (B=2·2 %, P=0·024). We conclude that diet has a very limited association with Fe status in Chinese adults consuming a traditional Chinese diet, and a predominantly plant-based diet may not be necessarily responsible for poor Fe status.

Hepcidin is a Better Predictor of Iron Stores in Premenopausal Women than Blood Loss or Dietary Intake

The relationship between dietary intake, circulating hepcidin and iron status in free-living premenopausal women has not been explored. This cross-sectional study aimed to identify dietary determinants of iron stores after accounting for blood loss and to determine whether iron intake predicts iron stores independently of hepcidin in a sample of Australian women. Three hundred thirty eight women aged 18-50 years were recruited. Total intake and food sources of iron were determined via food frequency questionnaire; the magnitude of menstrual losses was estimated by self-report; and blood donation volume was quantified using blood donation records and self-reported donation frequency. Serum samples were analysed for ferritin, hepcidin and C-reactive protein concentrations. Linear regression was used to investigate associations. Accounting for blood loss, each 1 mg/day increase in dietary iron was associated with a 3% increase in iron stores (p = 0.027); this association was not independent of hepcidin. Hepcidin was a more influential determinant of iron stores than blood loss and dietary factors combined (R² of model including hepcidin = 0.65; R² of model excluding hepcidin = 0.17, p for difference <0.001), and increased hepcidin diminished the positive association between iron intake and iron stores. Despite not being the biggest contributor to dietary iron intake, unprocessed meat was positively associated with iron stores, and each 10% increase in consumption was associated with a 1% increase in iron stores (p = 0.006). No other dietary factors were associated with iron stores. Interventions that reduce hepcidin production combined with dietary strategies to increase iron intake may be important means of improving iron status in women with depleted iron stores.

Prevalence of iron-deficiency anaemia and risk factors in 1010 adolescent girls from rural Maharashtra, India: a cross-sectional survey

OBJECTIVE

Iron-deficiency anaemia (IDA) is the most common nutritional disorder observed in adolescent girls in India. Our aim was to investigate the prevalence and risk factors associated with IDA in rural Maharashtra, India, to address current evidence gaps.

STUDY DESIGN

Cross-sectional survey.

METHODS

The study recruited 13- to 17-year-old adolescent girls living in 34 villages of Osmanabad district. Data were collected on individual health, dietary, sociodemographic factors, and anthropometric measurements were taken. Haemoglobin (Hb) levels were measured using Sahli's haemometer. Logistic and linear regressions were used to identify risk factors associated with IDA and Hb levels, respectively.

RESULTS

Among 1010 adolescent girls (response rate 97.5%), the mean Hb was 10.1 g/dl (standard deviation = 1.3), and 87% had anaemia (Hb < 12 g/dl). The prevalence of mild (11.0-11.9 g/dl), moderate (8.0-10.9 g/dl) and severe (Hb ≤ 7.9 g/dl) anaemia was 17%, 65% and 5%, respectively. Anaemia likelihood increased significantly with age (odds ratio (OR): 1.41 per year, 95% confidence interval (CI): 1.17-1.70). Factors associated with decreased anaemia risk were mid-upper arm circumference (MUAC) ≥22 cm (OR: 0.51, 95% CI: 0.31-0.82), ≥3 days/week consumption of fruit (OR: 0.35, 95% CI: 0.23-0.54) or rice (OR: 0.39, 95% CI: 0.17-0.91), and incomplete schooling (OR: 0.47, 95% CI: 0.24-0.91). In the final model lower age, MUAC and fruit consumption were significantly associated with Hb level.

CONCLUSION

Anaemia prevalence was extremely high among adolescent girls in rural areas of Maharashtra. Whilst we identified risk factors that could be used for targeting interventions, there is urgent need of comprehensive preventative interventions for the whole adolescent girl population.

Genome-wide association study of serum iron phenotypes in premenopausal women of European descent

A genome-wide association study was performed on 1130 premenopausal women to detect common variants associated with three serum iron-related phenotypes. Total iron binding capacity was strongly associated (p=10(-14)) with variants in and near the TF gene (transferrin), the serum iron transporting protein, and with variants in HFE (p=4×10(-7)), which encodes the human hemochromatosis gene. Association was also detected between percent iron saturation (p=10(-8)) and variants in the chromosome 6 region containing both HFE and SLC17A2, which encodes a phosphate transport protein. No significant associations were detected with serum iron, but variants in HFE were suggestive (p=10(-6)). Our results corroborate prior studies in older subjects and demonstrate that the association of these genetic variants with iron phenotypes can be detected in premenopausal women.

Is Higher Consumption of Animal Flesh Foods Associated with Better Iron Status among Adults in Developed Countries? A Systematic Review

Iron deficiency (ID) is the most prevalent nutrient deficiency within the developed world. This is of concern as ID has been shown to affect immunity, thermoregulation, work performance and cognition. Animal flesh foods provide the richest and most bioavailable source of dietary (haem) iron, however, it is unclear whether low animal flesh diets contribute to ID. This systematic review aimed to investigate whether a higher consumption of animal flesh foods is associated with better iron status in adults. CINAHL, Cochrane, EMBASE and MEDLINE were searched for published studies that included adults (≥18 years) from developed countries and measured flesh intakes in relation to iron status indices. Eight experimental and 41 observational studies met the inclusion criteria. Generally, studies varied in population and study designs and results were conflicting. Of the seven high quality studies, five showed a positive association between animal flesh intake (85-300 g/day) and iron status. However, the optimum quantity or frequency of flesh intake required to maintain or achieve a healthy iron status remains unclear. Results show a promising relationship between animal flesh intake and iron status, however, additional longitudinal and experimental studies are required to confirm this relationship and determine optimal intakes to reduce ID development.

Dietary determinants of and possible solutions to iron deficiency for young women living in industrialized countries: a review

Iron deficiency is a concern in both developing and developed (industrialized) countries; and young women are particularly vulnerable. This review investigates dietary determinants of and possible solutions to iron deficiency in young women living in industrialized countries. Dietary factors including ascorbic acid and an elusive factor in animal protein foods (meat; fish and poultry) enhance iron absorption; while phytic acid; soy protein; calcium and polyphenols inhibit iron absorption. However; the effects of these dietary factors on iron absorption do not necessarily translate into an association with iron status and iron stores (serum ferritin concentration). In cross-sectional studies; only meat intake has consistently (positively) been associated with higher serum ferritin concentrations. The enhancing effects of ascorbic acid and meat on iron absorption may be negated by the simultaneous consumption of foods and nutrients which are inhibitory. Recent cross-sectional studies have considered the combination and timing of foods consumed; with mixed results. Dietary interventions using a range of focused dietary measures to improve iron status appear to be more effective than dietary approaches that focus on single nutrients or foods. Further research is needed to determine optimal dietary recommendations for both the prevention and treatment of iron deficiency.

Sex differences in iron status and hepcidin expression in rats

Studies have shown that men and women exhibit significant differences regarding iron status. However, the effects of sex on iron accumulation and distribution are not well established. In this study, female and male Sprague-Dawley rats were killed at 4 months of age. Blood samples were analyzed to determine the red blood cell (RBC) count, hemoglobin (Hb) concentration, hematocrit (Hct), and mean red blood cell volume (MCV). The serum samples were analyzed to determine the concentrations of serum iron (SI), transferrin saturation (TS), ferritin, soluble transferrin receptor (sTfR), and erythropoietin (EPO). The tissue nonheme iron concentrations were measured in the liver, spleen, bone marrow, kidney, heart, gastrocnemius, duodenal epithelium, lung, pallium, cerebellum, hippocampus, and striatum. Hepatic hepcidin expression was detected by real-time PCR analysis. The synthesis of ferroportin 1 (FPN1) in the liver, spleen, kidney, and bone marrow was determined by Western blot analysis. The synthesis of duodenal cytochrome B561 (DcytB), divalent metal transporter 1 (DMT1), FPN1, hephaestin (HP) in the duodenal epithelium was also measured by Western blot analysis. The results showed that the RBC, Hb, and Hct in male rats were higher than those in female rats. The SI and plasma TS levels were lower in male rats than in female rats. The levels of serum ferritin and sTfR were higher in male rats than in female rats. The EPO levels in male rats were lower than that in female rats. The nonheme iron contents in the liver, spleen, bone marrow, and kidney in male rats were also lower (56.7, 73.2, 60.6, and 61.4 % of female rats, respectively). Nonheme iron concentrations in the heart, gastrocnemius, duodenal epithelium, lung, and brain were similar in rats of both sexes. A moderate decrease in hepatic hepcidin mRNA content was also observed in male rats (to 56.0 % of female rats). The levels of FPN1 protein in the liver, spleen, and kidney were higher in male rats than in female rats. There was no significant change in FPN1 expression in bone marrow. Significant difference was also not found in DcytB, DMT1, FPN1, and HP protein levels in the duodenal epithelium between male and female rats. These data suggest that iron is distributed differently in male and female rats. This difference in iron distribution may be associated with the difference in the hepcidin level.

Blood donation, being Asian, and a history of iron deficiency are stronger predictors of iron deficiency than dietary patterns in premenopausal women

This study investigated dietary patterns and nondietary determinants of suboptimal iron status (serum ferritin < 20 μg/L) in 375 premenopausal women. Using multiple logistic regression analysis, determinants were blood donation in the past year [OR: 6.00 (95% CI: 2.81, 12.82); P < 0.001], being Asian [OR: 4.84 (95% CI: 2.29, 10.20); P < 0.001], previous iron deficiency [OR: 2.19 (95% CI: 1.16, 4.13); P = 0.016], a “milk and yoghurt” dietary pattern [one SD higher score, OR: 1.44 (95% CI: 1.08, 1.93); P = 0.012], and longer duration of menstruation [days, OR: 1.38 (95% CI: 1.12, 1.68); P = 0.002]. A one SD change in the factor score above the mean for a “meat and vegetable” dietary pattern reduced the odds of suboptimal iron status by 79.0% [OR: 0.21 (95% CI: 0.08, 0.50); P = 0.001] in women with children. Blood donation, Asian ethnicity, and previous iron deficiency were the strongest predictors, substantially increasing the odds of suboptimal iron status. Following a “milk and yoghurt” dietary pattern and a longer duration of menstruation moderately increased the odds of suboptimal iron status, while a “meat and vegetable” dietary pattern reduced the odds of suboptimal iron status in women with children.

A simple and feasible questionnaire to estimate menstrual blood loss: relationship with hematological and gynecological parameters in young women

Background

Menstrual blood loss (MBL) has been shown to be an important determinant in iron status, work performance and well-being. Several methods have been developed to estimate MBL, the standard quantitative method however has limited application in clinical practice as it is expensive and requires women to collect, store and submit their sanitary products for analysis. We therefore aimed to develop a MBL-score based on a questionnaire, and to validate it by several hematological and biochemical parameters in women of childbearing age.

Methods

A total of 165 healthy young women were recruited. Hematological (hematocrit, hemoglobin, erythrocyte, leucocyte and platelet counts) and iron status (serum iron, serum ferritin, serum transferrin, and total iron binding capacity) parameters were analyzed at baseline. Women were asked to fulfill two gynecological questionnaires: a general questionnaire, to inform about the volunteer’s general menstrual characteristics; and a MBL questionnaire, to provide details of the duration of menstruation, number of heavy blood loss days, and number and type of pads and/or tampons used during the heaviest bleeding day, for all consecutive menstrual periods during 16 weeks. A MBL-score was calculated for each period and women, and its reliability determined by the Cronbach’s alpha coefficient. Pearson’s linear correlation tests were performed between blood parameters and the MBL-score. Two clusters were formed according the MBL-score (cluster 1: low MBL and cluster 2: high MBL).

Results

Significant higher MBL-score was observed in women who reported having a history of anemia (p = 0.015), staining the bed at night during menstruation (p < 0.001) and suffering inter-menstrual blood loss (p = 0.044), compared to those who did not. Women who used hormonal contraceptives presented lower MBL-scores than the others (p = 0.004). The MBL-score was negatively associated with log-ferritin (p = 0.006) and platelet count (p = 0.011). Women in cluster 1 presented higher ferritin (p = 0.043) than women in cluster 2.

Conclusions

We developed an easy and practical method for estimating menstrual blood loss based on a score calculated from a questionnaire in healthy women at childbearing age. The MBL-score is highly reliable and reflects menstrual blood loss validated by hematological and biochemical parameters.

Influence of diet, menstruation and genetic factors on iron status: a cross-sectional study in Spanish women of childbearing age

The aim of this study was to investigate the combined influence of diet, menstruation and genetic factors on iron status in Spanish menstruating women (n = 142). Dietary intake was assessed by a 72-h detailed dietary report and menstrual blood loss by a questionnaire, to determine a Menstrual Blood Loss Coefficient (MBLC). Five selected SNPs were genotyped: rs3811647, rs1799852 (Tf gene); rs1375515 (CACNA2D3 gene); and rs1800562 and rs1799945 (HFE gene, mutations C282Y and H63D, respectively). Iron biomarkers were determined and cluster analysis was performed. Differences among clusters in dietary intake, menstrual blood loss parameters and genotype frequencies distribution were studied. A categorical regression was performed to identify factors associated with cluster belonging. Three clusters were identified: women with poor iron status close to developing iron deficiency anemia (Cluster 1, n = 26); women with mild iron deficiency (Cluster 2, n = 59) and women with normal iron status (Cluster 3, n = 57). Three independent factors, red meat consumption, MBLC and mutation C282Y, were included in the model that better explained cluster belonging (R2 = 0.142, p < 0.001). In conclusion, the combination of high red meat consumption, low menstrual blood loss and the HFE C282Y mutation may protect from iron deficiency in women of childbearing age. These findings could be useful to implement adequate strategies to prevent iron deficiency anemia.

Improvements in iron status and cognitive function in young women consuming beef or non-beef lunches

Iron status is associated with cognitive performance and intervention trials show that iron supplementation improves mental function in iron-deficient adults. However, no studies have tested the efficacy of naturally iron-rich food in this context. This investigation measured the hematologic and cognitive responses to moderate beef consumption in young women. Participants (n=43; age 21.1±0.4 years) were randomly assigned to a beef or non-beef protein lunch group [3-oz (85 g), 3 times weekly] for 16 weeks. Blood was sampled at baseline, and weeks 8 and 16, and cognitive performance was measured at baseline and week 16. Body iron increased in both lunch groups (p<0.0001), with greater improvement demonstrated in women with lower baseline body iron (p<0.0001). Body iron had significant beneficial effects on spatial working memory and planning speed (p<0.05), and ferritin responders (n=17) vs. non-responders (n=26) showed significantly greater improvements in planning speed, spatial working memory strategy, and attention (p<0.05). Lunch group had neither significant interactions with iron status nor consistent main effects on test performance. These findings support a relationship between iron status and cognition, but do not show a particular benefit of beef over non-beef protein consumption on either measure in young women.

Prevalence of anemia and associated factors in child bearing age women in riyadh, saudi arabia

Objective. To determine the prevalence and risk factors for anemia in child bearing age women in Riyadh, Saudi Arabia. Design. Cross-sectional survey was conducted using two-stage cluster sampling. 25 clusters (primary health care centers (PHCC)) were identified from all over Riyadh, and 45–50 households were randomly selected from each cluster. Eligible women were invited to PHCC for questionnaire filling, anthropometric measurements, and complete blood count. Blood hemoglobin was measured with Coulter Cellular Analysis System using light scatter method. Setting. PHCC. Subjects. 969 (68%) women out of 1429 women were included in the analysis. Results. Mean hemoglobin was 12.35 (±1.80) g/dL, 95% CI 12.24–12.46 with interquartile range of 1.9. Anemia (Hb <12 g/dL) was present in 40% (390) women. Mean (±SD) for MCH, MCV, MCHC, and RDW was 79.21 (±12.17) fL, 26.37 (±6.21) pg, 32.36 (±4.91) g/dL, and 14.84 (±4.65)%, respectively. Multivariate logistic regression revealed that having family history of iron deficiency anemia (OR 2.91, 95% CI 1.78–4.76) and infrequent intake of meat (OR 1.54, 95%CI 1.15–2.05) were associated with increased risk of anemia, whereas increasing body mass index (OR 0.95, 95% CI 0.92–0.97) was associated with reduced risk of anemia. Conclusion. Women should be educated about proper diet and reproductive issues in order to reduce the prevalence of anemia in Saudi Arabia.

Iron status and dietary iron intake of female blood donors

BACKGROUND

The aim was to assess iron status and dietary iron intake in a sample of premenopausal female regular and new blood donors.

STUDY DESIGN AND METHODS

Premenopausal women blood donors were invited to participate. Blood samples were analyzed for serum ferritin and hemoglobin. An iron checklist assessed dietary iron intake. Donors were classified as regular donors or new donors.

RESULTS

Twenty-one new donors (mean [SD] age, 28.6 [6.0] years; body mass index [BMI], 25.6 [4.5] kg/m(2) ) and 172 regular donors (mean age, 29.4 [5.5] years; BMI, 24.7 [3.8] kg/m(2) ) participated. Fifty percent of regular donors and 24% of new donors had depleted iron stores (serum ferritin <15 μg/L; difference p = 0.036). Dietary iron intake was higher in regular donors (mean [SE], 12.6 [0.7] mg/day) compared to new donors (9.9 [0.4] mg/day; p = 0.006). Eighty-five percent of regular donors and 79% of new donors met the estimated average requirement for iron.

CONCLUSIONS

Despite the fact that most of these donors had an adequate dietary iron intake, more than half of the blood donors had depleted iron stores. Increasing dietary iron intake through supplements and/or dietary means is expected to be necessary to maintain adequate iron status in this group.

A randomized, double-blind clinical study on the safety and tolerability of an iron multi-amino acid chelate preparation in premenopausal women

ABSTRACT Considerable risk of iron deficiency has been identified in premenopausal women because of the adverse effects associated with commercial iron preparations. This study examined the safety and tolerability of a novel iron multi-amino acid chelate (IMAAC) preparation in premenopausal women. A single-centre, randomized, double-blind, three-arm placebo-controlled (n = 60) study was conducted where subjects received one of three test materials: IMAAC (600 mg) or ferrous sulfate (600 mg) each containing 25 mg of elemental iron, or placebo as a single daily dose for 7 days. After testing, there were no significant differences found in any of the hematological outcomes between the different test groups. The safety analyses showed that a significantly (p = .044) higher number of patients reported adverse events when taking the ferrous sulfate supplement compared to IMAAC. A significantly lower number of adverse effects (p = .008) were reported by subjects on IMAAC. The current study demonstrated the superiority of the IMAAC preparation over ferrous sulfate with regards to tolerability and adverse effects.

The association between the macronutrient content of maternal diet and the adequacy of micronutrients during pregnancy in the Women and Their Children’s Health (WATCH) study

Nutrition during pregnancy can induce alterations in offspring phenotype. Maternal ratio of protein to non-protein (P:NP) energy has been linked to variations in offspring body composition and adult risk of metabolic disease. This study describes the dietary patterns of pregnant women by tertiles of the P:NP ratio and compares diet to Australian recommendations. Data are from 179 Australian women enrolled in the Women and Their Children's Health Study. Diet was assessed using a validated 74-item food frequency questionnaire. Food group servings and nutrient intakes were compared to the Australian Guide to Healthy Eating and Australian Nutrient Reference Values. Higher maternal P:NP tertile was positively associated with calcium (P = 0.003), zinc (P = 0.001) and servings of dairy (P = 0.001) and meat (P = 0.001) food groups, and inversely associated with the energy dense, nutrient poor non-core (P = 0.003) food group. Micronutrient intakes were optimized with intermediate protein (18%E-20%E), intermediate fat (28%E-30%E) and intermediate carbohydrate (50%E-54%E) intakes, as indicated in tertile two. Results suggest a moderate protein intake may support pregnant women to consume the largest variety of nutrients across all food groups.

Iron status and self-perceived health, well-being, and fatigue in female university students living in New Zealand

OBJECTIVE

To determine the relationship between iron depletion and self-perceived health, well-being, and fatigue in a female university student population living in New Zealand.

METHODS

A total of 233 women aged 18-44 years studying at Massey University, Auckland, were included in this cross-sectional analysis. Serum ferritin (SF), hemoglobin (Hb), and C-reactive protein (CRP) were analyzed from a venipuncture blood sample. Participants completed the SF-36v2 General Health Survey (SF-36) and the Multidimensional Fatigue Symptom Inventory-Short Form (MFSI-SF) questionnaire, and anthropometric measurements (height and weight) and data on demographics, lifestyle, and medical history were obtained. Characteristics of iron-sufficient (SF ≥ 20 μg/L, Hb ≥ 120 g/L) and iron-depleted (SF < 20 μg/L, Hb ≥ 120 g/L) participants were compared, and multiple regression analyses were carried out to determine predictors of health, well-being, and fatigue using a p value of <0.01 to indicate statistical significance because multiple comparisons were being made.

RESULTS

There were no significant differences in self-perceived health and well-being determined using the SF-36 questionnaire between women who were iron sufficient and women who were iron depleted. Although MFSI-SF physical fatigue was significantly lower in those with iron depletion (p = 0.008), it was not predicted by current iron status in a multivariate model controlling for factors expected to be associated with iron status and fatigue (p = 0.037). However, smoking, a history of suboptimal iron status, and having a current medical condition were significant (negative) predictors of MFSI-SF physical fatigue, explaining 22.5% of the variance (p < 0.001). There were no significant differences in the other measures of fatigue determined using the MFSI-SF between women who were iron sufficient and those who were iron depleted.

CONCLUSIONS

Women with iron depletion did not differ significantly from women who were iron sufficient with regard to self-perceived health, well-being, or fatigue. Future studies investigating fatigue should control for previous diagnosis of suboptimal iron status, smoking, and presence of a medical condition.

Anemia, iron deficiency, and stress fractures in female combatants during 16 months

Yanovich, R, Merkel, D, Israeli, E, Evans, RK, Erlich, T, and Moran, DS. Anemia, iron deficiency, and stress fractures in female combatants during 16 months. J Strength Cond Res 25(12): 3412-3421, 2011-The purpose of this study is to evaluate the hematological profile of military recruits in different settings and training programs and to investigate the link between anemia and iron deficiency with stress fracture (SF) occurrence. We surveyed 3 groups of recruits for 16 months: 221 women (F) and 78 men (M) from 3 different platoons of a gender-integrated combat battalion and a control group (CF) of 121 female soldiers from a noncombat unit. Data were fully collected upon induction and at 4 and 16 months from 48F, 21M, and 31CF. Blood tests, anthropometry, physical aerobic fitness, and SF occurrence were evaluated. On induction day, 18.0 and 19.0% of F and CF were found to be anemic, and 61.4 and 50.9%, respectively, were found to have iron deficiency, whereas 7.7% of M were found to be anemic and 10.2% iron deficient. During the 4 months of army basic training (ABT), anemia and iron deficiency prevalence did not change significantly in any group. After 16-months, anemia prevalence decreased by 8% among F and CF and abated in M. Iron deficiency was prevalent in 50.0, 59.4, and 18.8% of F, CF, and M, respectively. Stress fractures were diagnosed in 14 F during ABT, and they had a significantly higher prevalence (p < 0.05) of anemia and iron deficiency anemia compared to F without SFs. The observed link between anemia and iron deficiency on recruitment day and SFs suggests the importance of screening female combat recruits for these deficiencies. To minimize the health impact of army service on female soldiers, preventative measures related to anemia and iron deficiency should be administered. Further research is needed for evaluating the influence of low iron in kosher meat as a possible explanation for the high prevalence of iron deficiency among young Israeli recruits.

Iron modifies plasma FGF23 differently in autosomal dominant hypophosphatemic rickets and healthy humans

CONTEXT

In autosomal dominant hypophosphatemic rickets (ADHR), fibroblast growth factor 23 (FGF23) resists cleavage, causing increased plasma FGF23 levels. The clinical phenotype includes variable onset during childhood or adulthood and waxing/waning of hypophosphatemia. Delayed onset after puberty in females suggests iron status may be important.

OBJECTIVE

Studies were performed to test the hypothesis that plasma C-terminal and intact FGF23 concentrations are related to serum iron concentrations in ADHR.

DESIGN AND SETTING

Cross-sectional and longitudinal studies of ADHR and a cross-sectional study in healthy subjects were conducted at an academic medical center.

PARTICIPANTS

Participants included 37 subjects with ADHR mutations from four kindreds and 158 healthy adult controls.

MAIN OUTCOME MEASURE

The relationships of serum iron concentrations with plasma C-terminal and intact FGF23 concentrations were evaluated.

RESULTS

Serum phosphate and 1,25-dihydroxyvitamin D correlated negatively with C-terminal FGF23 and intact FGF23 in ADHR but not in controls. Serum iron was negatively correlated to both C-terminal FGF23 (r = -0.386; P < 0.05) and intact FGF23 (r = -0.602; P < 0.0001) in ADHR. However, control subjects also demonstrated a negative relationship of serum iron with C-terminal FGF23 (r = -0.276; P < 0.001) but no relationship with intact FGF23. Longitudinally in ADHR subjects, C-terminal FGF23 and intact FGF23 concentrations changed negatively with iron concentrations (P < 0.001 and P = 0.055, respectively), serum phosphate changed negatively with C-terminal FGF23 and intact FGF23 (P < 0.001), and there was a positive relationship between serum iron and phosphate (P < 0.001).

CONCLUSIONS

Low serum iron is associated with elevated FGF23 in ADHR. However, in controls, low serum iron was also associated with elevated C-terminal FGF23, but not intact FGF23, suggesting cleavage maintains homeostasis despite increased FGF23 expression.

Iron, meat and health

This article is a summary of the publication "Iron and Health" by the Scientific Advisory Committee on Nutrition (SACN) to the U.K. Government (2010), which reviews the dietary intake of iron and the impact of different dietary patterns on the nutritional and health status of the U.K. population. It concludes that several uncertainties make it difficult to determine dose-response relationships or to confidently characterize the risks associated with iron deficiency or excess. The publication makes several recommendations concerning iron intakes from food, including meat, and from supplements, as well as recommendations for further research.

Gold kiwifruit consumed with an iron-fortified breakfast cereal meal improves iron status in women with low iron stores: a 16-week randomised controlled trial

Ascorbic acid, and more recently, the carotenoids lutein and zeaxanthin have been shown to enhance Fe absorption. However, it is not clear whether Fe status improves when foods high in ascorbic acid and carotenoids are consumed with Fe-fortified meals. The present study aimed to investigate whether consuming highv.low ascorbic acid-, lutein- and zeaxanthin-rich fruit (gold kiwifruitv.banana) with Fe-fortified breakfast cereal and milk improved Fe status in women with low Fe stores. Healthy women aged 18–44 years (n89) with low Fe stores (serum ferritin ≤ 25 μg/l and Hb ≥ 115 g/l) were randomly stratified to receive Fe-fortified breakfast cereal (16 mg Fe as ferrous sulfate), milk and either two gold kiwifruit or one banana (164 mgv.not detectable ascorbic acid; 526v.22·90 μg lutein and zeaxanthin, respectively) at breakfast every day for 16 weeks. Biomarkers of Fe status and dietary intake were assessed at baseline and end in the final sample (n69). Median serum ferritin increased significantly in the kiwifruit group (n33) compared with the banana group (n36), with 10·0 (25th, 75th percentiles 3·0, 17·5)v.1·0 (25th, 75th percentiles − 2·8, 6·5) μg/l (P < 0·001). Median soluble transferrin receptor concentrations decreased significantly in the kiwifruit group compared with the banana group, with − 0·5 (25th, 75th percentiles − 0·7, − 0·1)v.0·0 (25th, 75th percentiles − 0·3, 0·4) mg/l (P = 0·001). Consumption of an Fe-fortified breakfast cereal with kiwifruit compared with banana improved Fe status. Addition of an ascorbic acid-, lutein- and zeaxanthin-rich fruit to a breakfast cereal fortified with ferrous sulfate is a feasible approach to improve Fe status in women with low Fe stores.

Hormonal contraceptive practices in young Australian women (≤ 25 years) and their possible impact on menstrual frequency and iron requirements

OBJECTIVES

To investigate the hormonal contraceptive practices of female university students aged ≤ 25 years, their menstrual bleeding frequency, and interest in contraceptive regimens that reduce menstrual frequency or duration.

STUDY DESIGN

A 20-item questionnaire was distributed to female students at Griffith University, Gold Coast campus. This included questions relating to: demographics, menstrual bleeding frequency, current contraceptive practices, and interest in future oral contraceptive regimens that reduce menstrual bleeding frequency and duration.

MAIN OUTCOME MEASURES

Determination of hormonal contraceptive practices and menstrual bleeding frequency undertaken by the sample population.

RESULTS

Eight hundred and fifty one participants completed the questionnaire, ~ 2/3rds of respondents are currently using a hormonal contraceptive (66% of all respondents), with the oral contraceptive pill (OCP) being most common. Most women (73%) reported monthly menstruation, although 16% indicated that they sometimes missed their monthly period, with bleeding every two months. Of all OCP users, approximately 2/3rds have skipped their monthly period at some time, the most common reasons being for convenience (89%). Approximately 70% of respondents were interested in OCP regimens that reduced frequency or duration of menstruation.

CONCLUSION

OCP use is popular amongst Australian university women, with many being interested in the concept of using the OCP to delay menstruation. Given this interest and the availability of hormonal contraceptives that reduce menstrual frequency and duration, assessing the impact of reduced menstrual blood loss on iron stores may be warranted.

Iron deficiency in women and its potential impact on military effectiveness

Iron deficiency is recognized as a significant health concern for women of childbearing age in the civilian population. In the military, most women are of childbearing age. Not only do they carry the normal risks for developing iron deficiency, but they also have the added threats of possible decreased choices of food high in iron content, increased physical activity, and weight loss. This can put these women at risk for decreased energy efficiency and impaired cognitive performance. This article describes the pathophysiology of iron deficiency and iron deficiency anemia, the consequences of each, and the need to routinely screen military women for iron depletion.

Influence of an iron intervention on the zinc status of young adult New Zealand women with mild iron deficiency

Interventions to combat mild Fe deficiency in women of childbearing age may affect Zn nutriture. We used dietary and laboratory indices to assess change in Zn status during a 4-month partially blinded placebo-controlled Fe intervention in women with low Fe stores (serum ferritin < 20 μg/l and Hb ≥ 120 g/l) from Dunedin, New Zealand. Subjects aged 18–40 years were randomly assigned to three groups: dietary advice (diet group; DG;n29), daily Fe supplement with meals (supplement group; SG;n23; 50 mg Fe as amino acid chelate) and placebo (placebo group; PG,n26). A validated semi-quantitative FFQ (SFFQ) was administered at baseline, and at 4, 8 and 15 weeks; fasting morning blood samples were assayed for serum Zn, alkaline phosphatase (ALP) and C-reactive protein at baseline, and at 4, 8, 12 and 16 weeks; hair Zn and taste detection thresholds by electrogustometry were measured at baseline and at 16 weeks. Intakes of flesh foods and vitamin C but not Zn or Fe increased, whereas phytate and phytate:Zn molar ratios decreased (allP ≤ 0·01) in the DG compared with the PG and SG, based on three SFFQ. Serum Zn increased in both the DG and PG (adjusted,P ≤ 0·002), so the between-group difference was not significant; the lack of a parallel rise in the SG was significant when compared with the PG (P = 0·02). ALP activity (but not hair Zn or taste acuity) followed a similar trend. In conclusion, Zn status was not improved compared with placebo by an Fe-based dietary intervention. However, a daily moderate-dose Fe supplement with meals appeared to lower Zn status in these young adult women.

Burden of anemia and its socioeconomic determinants among adolescent girls in India

BACKGROUND

Anemia is still one of India's major public health problems, especially among adolescent girls.

OBJECTIVE

To investigate the severity and distribution of anemia among Indian adolescent girls aged 10 to 19 years and its association with socioeconomic and sociodemographic factors.

METHODS

The study used data from the District Level Household Survey, round 11, 2002-04, conducted under the Reproductive and Child Health Project. Data were collected on hemoglobin along with socioeconomic and sociodemographic factors of the households. The survey covered rural and urban areas of 35 states or union territories. Data from 177,670 adolescent girls were analyzed.

RESULTS

The highest prevalence of anemia (99.9%) was observed in Jharkhand in eastern India. The prevalence in the northeastern states was relatively low. The highest prevalence rates were observed among older girls (15 to 19 years), illiterate girls living in rural areas, girls in illiterate households, girls from households with a low standard of living, non-Christian girls, girls from Scheduled Tribes, girls living in west India, and married girls. The highest percentages of girls with normal hemoglobin were reported among Christian Scheduled Tribes (39.4%) and among girls in northeastern India (40.1%). Analysis by binary ordered logistic regression showed that anemia status did not depend on urban or rural residence or on age.

CONCLUSIONS

Enhancement of the economic status of families, especially poor families, is a prerequisite to the amelioration of anemia among adolescent girls. The level of education of the girls is also a major factor.

Iron intake does not significantly correlate with iron deficiency among young Japanese women: a cross-sectional study

Objectives

We evaluated the association of nutrient intake with Fe deficiency with regard to lifestyle factors and health condition in young Japanese women. Uniquely among developed countries, dietary habits render Japanese populations vulnerable to Fe deficiency, owing to their relatively low intake of Fe and high intake of Fe absorption inhibitors, such as green tea and soyabeans.

Design

A cross-sectional study.

Setting and subjects

The subjects were 1019 female Japanese dietetic students aged 18–25 years. Dietary habits during the preceding month were assessed using a previously validated, self-administered, diet history questionnaire. Blood analysis was performed to assess body Fe status. Subjects were categorized with Fe deficiency when their serum ferritin levels were <12 ng/ml. Twenty-nine dietary variables, i.e. intakes of energy, sixteen nutrients including Fe and twelve food groups, were analysed using multivariate logistic regression models adjusted for possible confounders.

Results

Of the subjects, 24·5 % were categorized with Fe deficiency. However, no dietary factors assessed were significantly associated with Fe deficiency. The risk of Fe deficiency was significantly lower in women with infrequent or no menstrual cycles than in those with regular cycles (OR = 0·58; 95 % CI 0·34, 1·00) and significantly higher in women with heavy menstrual flow than in women with average flow, albeit that these were self-reported (OR = 1·83; 95 % CI 1·35, 2·48).

Conclusions

These results suggest that dietary habits, including Fe intake, do not significantly correlate with Fe deficiency among young Japanese women.

Iron deficiency and the role of nutrition among female military recruits

The impact of iron deficiency is considerable when enhanced physical fitness is required. Female military recruits represent a unique population faced with intense physical and cognitive demands.

PURPOSE

To examine the prevalence of iron deficiency and the impact of dietary habits among female recruits in the Israel Defense Forces.

METHODS

Three hundred and forty-eight recruits completed the study (188 female combatants, 58 male combatants, and 92 noncombat females). Dietary intake was assessed using a Food Frequency Questionnaire. Blood samples were collected for complete blood cell count, iron indices, and vitamin B12. The common definitions for anemia and iron store deficiency were used as follows: hemoglobin <12 g x dL for females and <14 g x dL for males; serum ferritin <12 mg x dL.

RESULTS

The prevalence of iron deficiency and iron deficiency anemia was 29.8% and 12.8%, respectively, among female combatants. Similar data were found among noncombat females (27.2% and 17.4%, respectively) as compared with 5.2% and 0% among males. No significant difference in iron or total calorie intake was detected between subjects with iron deficiency (with or without anemia) when compared with subjects with normal iron status in the same study group. Plant sources constituted 85% of dietary iron source for females, in comparison to 73% for males. The contribution of red meat to the daily iron intake was 2% for females and 20% for males.

CONCLUSIONS

A high prevalence of iron deficiency was found among female recruits. Coupled with the iron loss during menstruation, inadequate iron intake may have a permissive role for iron deficiency in female recruits and is an important issue facing females in the military.

Blood loss is a stronger predictor of iron status in men than C282Y heterozygosity or diet

OBJECTIVE

To determine the relative importance of HFE gene, diet, lifestyle, and blood loss characteristics for predicting iron status in a sample of men aged 40 years or over.

DESIGN

Iron status (serum ferritin, transferrin saturation, soluble transferrin receptor) was measured in 44 C282Y heterozygote and 85 age- and BMI-matched wildtype men aged 40 years or over. Dietary intake of iron (total, heme and non-heme), and components known to influence iron bioavailability, was determined using a validated Meal-Based Intake Assessment Tool. Information on lifestyle and blood loss was obtained by questionnaire. Height and weight were measured to determine Quetelet's body mass index. Linear mixed models were used to determine the extent to which these variables predicted iron status.

RESULTS

C282Y heterozygosity was associated with 17% higher transferrin saturation (95% CI: 6%, 29%) but no difference in serum ferritin or soluble transferrin receptor concentrations. Blood donation was negatively associated with transferrin saturation (-13% (- 3%, -22%)) and serum ferritin (-58% (-44%, -68%)), and had a marginally significant positive association with soluble transferrin receptor concentration. Self-reported fecal blood loss was negatively associated with serum ferritin concentration (-35% (-54%, -7%)). Alcohol was the only dietary variable associated with iron status and was associated with all three of the iron status indices. Serum ferritin concentration was positively associated with body mass index (10% per unit increase (6%, 15%)).

CONCLUSIONS

Blood loss was a stronger predictor of iron status than either C282Y heterozygosity or diet in this population of men aged 40 years and over.

Evaluation of iron deficiency in young women in relation to oral contraceptive use

BACKGROUND

The purpose of this study was to identify the optimal measures for diagnosing iron deficiency (ID) in oral contraceptive (OC) users and nonusers, and to estimate ID frequency in relation to OC use.

STUDY DESIGN

Conventional biomarkers of iron status - serum ferritin, iron, transferrin (Tf) and transferrin saturation (TfS) - were compared with serum soluble Tf receptor (sTfR) and the sTfR/log ferritin ratio (sTfR-F index). Two hundred two healthy menstruating white Italian women (aged 24+/-4.8 years) were analyzed. Serum ferritin concentrations <12 microg/L were considered as ID.

RESULTS

ID was detected in 29.7% (60/202) of the study women. Fifty-nine women were OC users (59/202, 29.2%). OC use did not significantly affect ID prevalence (p=.24). However, OC use markedly increased Tf in OC users, who had an odds ratio (OR) of 9.3 (CI 3.8-22.7, p<.001) for elevated Tf >330 mg/dL. No other iron status measure was affected by OC. Of the markers for ID adjunctive to ferritin, an elevated sTfR-F index >or =1.5 showed the best performance. Specifically in OC users, the elevated sTfR-F index had better sensitivity (81.0% vs. 33.3%), specificity (94.7% vs. 92.1%), efficiency (89.8% vs. 71.2%), positive predictive value (89.5% vs. 70.0%) and negative predictive value (90.0% vs. 71.1%) than a TfS <15%. Additionally, the sTfR-F index allowed the identification of low iron stores in 4.5% (9/202) of women with ferritin > or =12 microg/L.

CONCLUSION

Among healthy OC users and non-OC users, the sTfR-F index had the highest performance for diagnosing ID compared with other serum markers adjunctive to ferritin measurements, whereas sTfR by itself had a low sensitivity. We showed that neither the sTfR nor sTfR-F index was affected by third-generation OC use. The sTfR measurement is useful in the diagnosis of ID, especially in women using OC, where Tf and TfS tests may be misleading.