Iron-deficiency anaemia and physical performance in adolescent girls from different ethnic backgrounds

Efficacy of iron supplementation on physical capacity in non-anaemic iron-deficient individuals: protocol for an individual patient data meta-analysis

BACKGROUND

A deficiency in iron stores is associated with various adverse health complications, which, if left untreated, can progress to states of anaemia, whereby there is significant detriment to an individual's work capacity and quality of life due to compromised erythropoiesis. The most common methods employed to treat an iron deficiency include oral iron supplementation and, in persistent and/or unresponsive cases, intravenous iron therapy. The efficacy of these treatments, particularly in states of iron deficiency without anaemia, is equivocal. Indeed, both randomised control trials and aggregate data meta-analyses have produced conflicting evidence. Therefore, this study aims to assess the efficacy of both oral and intravenous iron supplementation on physical capacity, quality of life, and fatigue scores in iron-deficient non-anaemic individuals using individual patient data (IPD) meta-analysis techniques.

METHODS

All potential studies, irrespective of design, will be sourced through systematic searches on the following databases: Cochrane Central Register of Controlled Trials, MEDLINE Ovid, Embase Ovid, Web of Science: Science Citation Index Expanded, Web of Science: Conference Proceedings Citation Index-Science, ClinicalTrials.gov, and World Health Organization (WHO) International Clinical Trials Registry Platform. Individual patient data from all available trials will be included and subsequently analysed in a two-stage approach. Predetermined subgroup and sensitivity analyses will be employed to further explain results.

DISCUSSION

The significance of this IPD meta-analysis is one of consolidating a clear consensus to better inform iron-deficient individuals of the physiological response associated with iron supplementation. The IPD approach, to the best of our knowledge, is novel for this research topic. As such, the findings will significantly contribute to the current body of evidence.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42020191739.

Effect of Anemia on Work Productivity in Both Labor- and Nonlabor-Intensive Occupations: A Systematic Narrative Synthesis

BACKGROUND

Anemia is highly prevalent particularly in low- and middle-income countries. Iron deficiency contributes to an estimated 50% of anemia cases. Iron interventions have become central to global anemia treatment and prevention; however, few iron interventions have been scaled up to the national level, despite their proven effectiveness. While both cross-sectional and interventional studies on the effect of anemia and iron supplementation on worker productivity have been conducted, there have been few systematic reviews conducted. As such, a synthesis of previously conducted primary research is warranted and may provide a more comprehensive overview of the strength of currently available evidence, potentially helping to inform national policy on matters relating to funding and legislation for population-level iron interventions.

OBJECTIVES

The objective of this study was to synthesize available evidence on the effect of both anemia and therapeutic iron interventions on productivity in working adults.

METHODS

All relevant English language studies were systematically obtained from both MEDLINE and EMBASE and assessed for evidence of differing productivity levels across groups stratified by iron intervention or anemia status. Potential mediating variables were reported, and the results were narratively summarized.

RESULTS

The available data from 12 included studies provide strong evidence that anemia negatively impacts occupational performance and that therapeutic iron interventions can yield substantial productivity gains.

CONCLUSIONS

Despite their limitations, these findings make an important contribution to the literature highlighting the impact of iron deficiency and population-wide iron interventions on work productivity and occupational performance.

Intravenous iron therapy for non-anaemic, iron-deficient adults

BACKGROUND

Iron deficiency is one of the most common nutritional deficiencies, and has a number of physiological manifestations. Early, or non-anaemic iron deficiency can result in fatigue and diminished exercise capacity. Oral iron preparations have a high incidence of intolerable side effects, and are ineffective in certain forms of iron deficiency. Consequently, intravenous iron preparations are increasingly used in the treatment of non-anaemic iron deficiency. The newer, more stable iron preparations in particular purport to have a lower incidence of side effects, and are now used across a range of different patient populations.

OBJECTIVES

To assess the effects of intravenous iron therapy in the treatment of adults with non-anaemic iron deficiency.

SEARCH METHODS

On 18 October 2019 we electronically searched CENTRAL, MEDLINE, Embase, two further databases and two trials registries 2019. We handsearched the references of full-text extracted studies, and contacted relevant study authors for additional data.

SELECTION CRITERIA

We included randomised controlled trials that compared any intravenous iron preparation to placebo in adults. We excluded other forms of comparison such as oral iron versus placebo, intramuscular iron versus placebo, or intravenous iron studies where other iron preparations were used as the comparator. We also excluded studies involving erythropoietin therapy or obstetric populations.

DATA COLLECTION AND ANALYSIS

Two review authors screened references for eligibility, extracted data and assessed risk of bias. We resolved differences in opinion through discussion and consensus, and where necessary, involved a third review author to adjudicate disputes. We contacted study authors to request additional data where appropriate. The primary outcome measures were haemoglobin concentration at the end of follow-up, and quality-of-life scores at end of follow-up. Secondary outcome measures were serum ferritin, peak oxygen consumption (as measured by cardiopulmonary exercise testing), adverse effects (graded as mild to moderate and severe) and bacterial infection. We pooled data for continuous outcomes, which we then reported as mean differences (MDs) with 95% confidence intervals (CIs). We reported quality-of-life metrics as standardised mean difference (SMD), and then converted them back into a more familiar measure, the Piper Fatigue Scale. We analysed dichotomous outcomes as risk ratios (RRs). Given an expected degree of heterogeneity, we used a random-effects model for all outcomes. We performed the analysis with the software package Review Manager 5.

MAIN RESULTS

This review includes 11 studies with 1074 participants. Outcome metrics for which data were available (haemoglobin concentration, quality-of-life scores, serum ferritin, peak oxygen consumption and mild to moderate adverse effects) were similar across the included studies. The incidence of severe adverse events across all studies was zero. None of the studies measured bacterial infection as a specific outcome metric. Substantial heterogeneity influenced the results of the meta-analysis, arising from differing patient populations, definitions of iron deficiency, iron preparations and dosing regimens, and time to end of follow-up. Consequently, many outcomes are reported with small group sizes and wide confidence intervals, with a subsequent downgrading in the quality of evidence. The level of bias in many included studies was high, further reducing confidence in the robustness of the results. We found that intravenous iron therapy may lead to a small increase in haemoglobin concentration of limited clinical significance compared to placebo (MD 3.04 g/L, 95% CI 0.65 to 5.42; I2 = 42%; 8 studies, 548 participants; low-quality evidence). Quality-of-life scores (Piper Fatigue Scale MD 0.73, 95% CI 0.29 to 1.18; I2 = 0%; studies = 3) and peak oxygen consumption (MD 2.77 mL/kg/min, 95% CI -0.89 to 6.43; I2 = 36%; 2 studies, 32 participants) were associated with very low-quality evidence, and we remain uncertain about the role of intravenous iron for these metrics. We were unable to present pooled estimates for the outcomes of serum ferritin at the end of follow-up or mild to moderate adverse effects due to extreme statistical heterogeneity. Ultimately, despite the results of the meta-analysis, the low- or very low-quality evidence for all outcomes precludes any meaningful interpretation of results beyond suggesting that further research is needed. We performed a Trial Sequential Analysis for all major outcomes, none of which could be said to have reached a necessary effect size.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to show benefit of intravenous iron preparations for the treatment of non-anaemic iron deficiency across a variety of patient populations, beyond stating that it may result in a small, clinically insignificant increase in haemoglobin concentration. However, the certainty for even this outcome remains limited. Robust data for the effectiveness of intravenous iron for non-anaemic iron deficiency is still lacking, and larger studies are required to assess the effect of this therapy on laboratory, patient-centric, and adverse-effect outcomes.

Prevention and Control of Anemia Amongst Children and Adolescents: Theory and Practice in India

Anemia is a major public health problem in India with prevalence of more than 50% amongst children and adolescents. The decline in the burden of anemia has been insignificant over the past 5 decades. The present review assesses the National Guidelines for Prevention and Control of Anemia in India, the current status of the program implementation and possible reasons for the continued high prevalence of anemia in the country.

Daily versus Weekly Iron Supplementation: Programmatic and Economic Implications for Indonesia

Available information on iron deficiency and anaemia among Indonesian population groups was analysed to identify the at-risk groups in Indonesia and to suggest more efficient intervention programmes to reduce its high prevalence. The results showed that the groups with the highest prevalence of anaemia were pregnant women (52.3%), working adult women (27.9%), pre-schoolers (27.1%), adolescent girls (21.1%), the elderly (10.9%), and primary-school children (6.8%). Pre-school children and adolescents need iron supplementation to provide enough iron for growth and cognitive functioning during childhood. Adolescent girls need iron supplementation to develop sufficient iron reserves before pregnancy and to improve working performance. Pregnant and lactating women also need iron supplementation. Strategies to control anaemia include improvement in dietary habits, food fortification, and supplementation. Unless feeding behaviour is changed or food fortification is adapted nationwide, oral iron supplementation remains the mainstay of the prevention and treatment of anaemia. Weekly supplementation has been shown to be an effective and economic method of supplementation. With the current approach of daily supplementation recommended by the World Health Organization, Indonesia would have to spend US$360 million annually, but weekly dosing would require only US$15 million to cover the same target population. Weekly dosing offers a practical and economic means of improving iron status in developing countries.

Intravenous iron therapy for non‐anaemic iron deficient adults

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To assess the effects of intravenous iron supplementation in the treatment of non‐anaemic iron deficiency in adult patients.

Common causes of dyspnoea in athletes: a practical approach for diagnosis and management

Key points

Educational aims

Dyspnoea during exercise is a common chief complaint in athletes and active individuals. It is not uncommon for dyspnoeic athletes to be diagnosed with asthma, “exercise-induced asthma” or exercise-induced bronchoconstriction based on their symptoms, but this strategy regularly leads to misdiagnosis and improper patient management. Dyspnoea during exercise can ultimately be caused by numerous respiratory and nonrespiratory conditions, ranging from nonpathological to potentially fatal in severity. As, such it is important for healthcare providers to be familiar with the many factors that can cause dyspnoea during exercise in seemingly otherwise-healthy individuals and have a general understanding of the clinical approach to this patient population. This article reviews common conditions that ultimately cause athletes to report dyspnoea and associated symptoms, and provides insight for developing an efficient diagnostic plan.

Dyspnoea, fatigue and underperformance are often interrelated symptoms in athletes, and may have various causeshttp://ow.ly/4nsYnk

Differences in Risk Factors for Anemia Between Adolescent and Adult Women

BACKGROUND

Iron deficiency anemia (IDA) affects 2%-5% of reproductive-age women. Screening is based on risk factors, such as a low-iron diet and menstruation. However, published IDA risk factors fail to consider age-related risks specific to adolescent women, potentially limiting identification of high-risk adolescents for objective testing. The goal of the study was to examine IDA risk factors in a nationally representative sample of younger (12-21 years) and older (22-49 years) reproductive-age women.

MATERIALS AND METHODS

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) 2003-2010. IDA was defined using hemoglobin, ferritin, soluble transferrin receptor, standard NHANES laboratory measures. Sex-, age-, and race-specific hemoglobin values defined anemia. Iron deficiency was calculated using ferritin and soluble transferrin receptor in the body iron formula. Logistic regression assessed the association of potential risk factors (race, body mass index, poverty, iron intake, tobacco/nicotine exposure, physical activity, menses, and contraceptive use) with IDA in younger and older women.

RESULTS

The prevalence of IDA was 2.4% and 5.5% among younger and older women, respectively. Among younger women, contraceptive use was marginally protective from IDA (risk ratio 0.50, 95% confidence interval [CI] 0.25-1.00). Among older women, significant variables included Black race (risk ratio 2.31, 95% CI 1.33-4.02) and increased years menstruating (≥25 years vs. <25 years; risk ratio 1.93, 95% CI 0.99-3.76).

CONCLUSIONS

Risk factors for IDA among older reproductive-age women do not apply to adolescent women. To better inform the timing and frequency of screening recommendations, further research must identify adolescent-specific IDA risk factors.

Impact of iron-fortified foods on Hb concentration in children (<10 years): a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To combine evidence from randomized controlled trials to assess the effect of Fe-fortified foods on mean Hb concentration in children (<10 years).

DESIGN

We conducted a meta-analysis of randomized, controlled, Fe-fortified feeding trials that evaluated Hb concentration. The weighted mean difference was calculated for net changes in Hb by using random-effects models. Meta-regression and covariate analyses were performed to explore the influence of confounders on the net pooled effect.

SETTING

Trials were identified through a systematic search of PubMed, the Cochrane Library and secondary references.

SUBJECTS

Eighteen studies covering 5142 participants were identified. The duration of feeding of fortified foods ranged from 6 to 12 months in these studies.

RESULTS

Eighteen studies were included and evaluated in the meta-analysis. The overall pooled estimate of Hb concentration showed a significant increase in the fortification group compared with the control group (weighted mean difference = 5·09 g/l; 95% CI 3·23, 6·95 g/l; I 2 = 90%, τ 2 = 18·37, P < 0·0001). Meta-regression analysis indicated that duration of feeding was positively related to the effect size (regression coefficient = 0·368; 95% CI 0·005, 0·731; P < 0·05). The net pooled effect size after removing the confounders was 4·74 (95% CI 3·08, 6·40) g/l.

CONCLUSIONS

We observed an association between intake of Fe-fortified foods and Hb concentration in children aged <10 years. Fe-fortified foods could be an effective strategy for reducing Fe-deficiency anaemia in children.

Iron status and dietary iron intake of vegetarian children from Poland

BACKGROUND/AIM

In Poland, vegetarian diets are becoming more and more popular. The aim of this study was to examine the effect of iron intake on iron status in vegetarian children.

METHODS

Dietary iron intake, iron food sources, blood count, serum iron, ferritin level and total iron-binding capacity were estimated in two groups of children, namely vegetarians (n = 22) and omnivores (n = 18) of both sexes, aged from 2 to 18 years. Seven-day food records were used to assess their diet.

RESULTS

Dietary iron intake in vegetarians and omnivores was low (up to 65.0 and 60.1% of the recommended dietary allowance). A significantly higher intake of vitamin C was observed in vegetarians compared with omnivores (p = 0.019). The main sources of iron in vegetarians were cereal products, followed by vegetables and mushroom products, then fruit. The prevalence of iron deficiency (ID) was higher in the vegetarian group (p = 0.023). The serum ferritin level and mean corpuscular volume in the vegetarians were also lower than in the omnivores (p = 0.01 and p = 0.014, respectively).

CONCLUSIONS

Children who follow a vegetarian diet may suffer from ID in spite of having a high vitamin C intake. This indicates the need to introduce dietary education and iron status monitoring.

Iron deficiency anemia in women across the life span

Anemia is a global health issue with disproportionately high prevalence in women. In addition to being an independent risk factor for decreased quality of life and increased morbidity and mortality, anemia in women has been linked to unfavorable outcomes of pregnancy and other issues for children born to anemic women. Iron deficiency is the leading cause of anemia in many populations. Guidelines recommend proactive screening for anemia, particularly in the preoperative setting. Once anemia is diagnosed, treatment should be based on etiology (most commonly, iron deficiency followed, in order of prevalence, by inflammation or chronic disease). Iron supplementation (oral and intravenous) offers safe and effective treatment for anemia associated with iron deficiency. Anemia of chronic disease may be more challenging to treat, and attention must be given to the underlying disease, along with use of hematinic agents. Given its enormous impact on the health and well-being of women and the availability of simple and effective treatment options, anemia should never be left unmanaged.

Prevalence and management of anemia in children, adolescents, and adults with inflammatory bowel disease

BACKGROUND

Children and adolescents with inflammatory bowel disease (IBD) are more likely to have Crohn's disease (CD) than ulcerative colitis (UC) and their disease tends to be more extensive and severe than in adults. We hypothesized that the prevalence of anemia would therefore be greater in children and adolescents than in adults attending IBD outpatient clinics.

METHODS

Using the WHO age-adjusted definitions of anemia we assessed the prevalence, severity, type, and response to treatment of anemia in patients attending pediatric, adolescent, and adult IBD clinics at our hospital.

RESULTS

The prevalence of anemia was 70% (41/59) in children, 42% (24/54) in adolescents, and 40% (49/124) in adults (P < 0.01). Overall, children (88% [36/41]) and adolescents (83% [20/24]) were more often iron-deficient than adults (55% [27/49]) (P < 0.01). Multivariate logistic regression showed that both active disease (odds ratio [OR], 4.7 95% confidence interval [CI], 2.5, 8.8) and attending the pediatric clinic (OR 3.7; 95% CI, 1.6, 8.4) but not the adolescent clinic predicted iron deficiency anemia. Fewer iron-deficient children (13% [5/36]) than adolescents (30% [6/20]) or adults (48% [13/27]) had been given oral iron (P < 0.05); none had received intravenous iron compared with 30% (6/20) adolescents and 41% (11/27) adults (P < 0.0001).

CONCLUSIONS

Anemia is even more common in children than in older IBD patients. Oral iron was given to half of adolescents and adults but, despite similar tolerance and efficacy, only a quarter of children with iron-deficient anemia. Reasons for the apparent underutilization of iron therapy include a perceived lack of benefit and concerns about side effects, including worsening of IBD activity.

Eating behaviour, body image, and self-esteem of adolescent girls in Malaysia

This cross-sectional study was undertaken with 489 secondary school girls, ages 15-17 years, to examine disordered eating behaviours of adolescent girls in Malaysia and to estimate associations with body weight, body-size discrepancy, and self-esteem. Dietary restraint, binge eating, body image, and self-esteem were assessed using the Restrained Eating scale of the Dutch Eating Behaviour Questionnaire, the Binge Scale Questionnaire, the Contour Drawing Rating Scale, and the Rosenberg Self-Esteem Scale, respectively. Pearson correlations estimated associations between variables. There were 3.1% underweight, 9.8% at risk of being overweight, and 8.6% overweight girls. A total of 87.3% were dissatisfied with their own body size. Dietary restraint and binge eating were reported by 36.0% and 35.4%, respectively. Body Mass Index (r = .34, p < .01) and body-size dissatisfaction (r = .24, p < .01) were significantly associated with dietary restraint and binge eating, but self-esteem (r = -.20, p < .001) was significantly associated only with binge eating.

Athletic induced iron deficiency: new insights into the role of inflammation, cytokines and hormones

Iron is utilised by the body for oxygen transport and energy production, and is therefore essential to athletic performance. Commonly, athletes are diagnosed as iron deficient, however, contrasting evidence exists as to the severity of deficiency and the effect on performance. Iron losses can result from a host of mechanisms during exercise such as hemolysis, hematuria, sweating and gastrointestinal bleeding. Additionally, recent research investigating the anemia of inflammation during states of chronic disease has allowed us to draw some comparisons between unhealthy populations and athletes. The acute-phase response is a well-recognised reaction to both exercise and disease. Elevated cytokine levels from such a response have been shown to increase the liver production of the hormone Hepcidin. Hepcidin up-regulation has a negative impact on the iron transport and absorption channels within the body, and may explain a potential new mechanism behind iron deficiency in athletes. This review will attempt to explore the current literature that exits in this new area of iron metabolism and exercise.

Impact of menstrual blood loss and diet on iron deficiency among women in the UK

Women of childbearing age are at risk of Fe deficiency if insufficient dietary Fe is available to replace menstrual and other Fe losses. Haem Fe represents 10–15 % of dietary Fe intake in meat-rich diets but may contribute 40 % of the total absorbed Fe. The aim of the present study was to determine the relative effects of type of diet and menstrual Fe loss on Fe status in women. Ninety healthy premenopausal women were recruited according to their habitual diet: red meat, poultry/fish or lacto-ovo-vegetarian. Intake of Fe was determined by analysing 7 d duplicate diets, and menstrual Fe loss was measured using the alkaline haematin method. A substantial proportion of women (60 % red meat, 40 % lacto-ovo-vegetarian, 20 % poultry/fish) had low Fe stores (serum ferritin <10 μg/l), but the median serum ferritin concentration was significantly lower in the red meat group (6·8 μg/l (interquartile range 3·3, 16·25)) than in the poultry/fish group (17·5 μg/l (interquartile range 11·3, 22·4) (P<0·01). The mean and standard deviation of dietary Fe intake were significantly different between the groups (P=0·025); the red meat group had a significantly lower intake (10·9 (sd 4·3) mg/d) than the lacto-ovo-vegetarians (14·5 (sd 5·5) mg/d), whereas that of the poultry/fish group (12·8 (sd 5·1) mg/d) was not significantly different from the other groups. There was no relationship between total Fe intake and Fe status, but menstrual Fe loss (P=0·001) and dietary group (P=0·040) were significant predictors of Fe status: poultry/fish diets were associated with higher Fe stores than lacto-ovo-vegetarian diets. Identifying individuals with high menstrual losses should be a key component of strategies to prevent Fe deficiency.

Risk factors for low iron intake and poor iron status in a national sample of British young people aged 4-18 years

OBJECTIVE

To examine the prevalence and dietary, sociodemographic and lifestyle risk factors of low iron intake and poor iron status in British young people.

DESIGN

National Diet and Nutrition Survey of young people aged 4-18 years.

SETTING

Great Britain, 1997.

SUBJECTS

In total, 1699 young people provided 7-day weighed dietary records, of which 11% were excluded because the participant reported being unwell with eating habits affected. Blood was obtained from 1193 participants, with iron status indicated by haemoglobin, serum ferritin and transferrin saturation.

RESULTS

Iron intakes were generally adequate in most young people aged 4-18 years. However, low iron intakes (below the Lower Reference Nutrient Intake) occurred in 44% of adolescent girls (11-18 years), being less prevalent with high consumption of breakfast cereals. Low haemoglobin concentration (<115 g l-1, 4-12 years; <120 or <130 g l-1, 13+ years for girls and boys, respectively) was observed in 9% of children aged 4-6 years, pubertal boys (11-14 years) and older girls (15-18 years). Adolescent girls who were non-Caucasians or vegetarians had significantly poorer iron status than Caucasians or meat eaters, independent of other risk factors. The three iron status indices were correlated significantly with haem, but not non-haem, iron intake.

CONCLUSIONS

Adolescent girls showed the highest prevalence of low iron intake and poor iron status, with the latter independently associated with non-Caucasian ethnicity and vegetarianism. Risk of poor iron status may be reduced by consuming (particularly lean red) meat or enhancers of non-haem iron absorption (e.g. fruit or fruit juice) in vegetarians.

The association between red and processed meat consumption and iron intakes and status among British adults

OBJECTIVE

To examine the association between consumption of red and processed meat (RPM) and iron intakes and status in adults.

DESIGN

Further analysis of the Dietary and Nutritional Survey of British Adults, a cross-sectional study of 2197 adults aged 16-64 years carried out in 1986/7.

SUBJECTS AND METHODS

Adults (836 men and 838 women) with serum ferritin measurements, who were not taking iron supplements, were classified into four groups according to RPM consumption (from 7-day weighed records). Iron absorbed was estimated from equations based on haem and non-haem iron and the influence of iron stores.

RESULTS

Women who ate least meat (<90 g day-1) had three times the risk of a low iron intake (below the Lower Reference Nutrient Intake) compared with high consumers of RPM (>140 g day-1). Men who ate no RPM also had a higher risk of low iron intake. Using an estimate of minimal values for iron losses, there was a twofold difference in the potential risk of negative iron balance between women non-RPM consumers and high RPM consumers. Status measurements indicated that, among women, anaemia was least prevalent (6%) among high consumers compared with 12-14% among average RPM consumers. Inverse trends were also observed for serum ferritin in both sexes.

CONCLUSIONS

Low consumption of RPM has implications for iron intakes and iron status in men and women, since the risk of negative iron balance and its consequences are increased. Dietary messages must consider these implications and provide appropriate advice.

Dietary restraint in relation to nutrient intake, physical activity and iron status in adolescent females

AIM

To investigate the prevalence of dietary restraint in a female adolescent population, and to examine the nutritional consequences of dietary restraint and its implications for iron status.

METHODS

A total of 64 adolescent females, aged 14-15 years, were recruited from two all-girl schools in central London. Nutrient intake, body weight, physical activity and iron status were measured. Findings were compared between three groups of subjects classified by dietary restraint.

RESULTS

Adolescents with a higher BMI percentile were more likely to be highly restrained. Scores on the dietary restraint psychometric measures were comparable with other UK studies in this age group. Energy intake was inversely related to dietary restraint (mean energy intake (SE) for each restraint group were: low 8.99 MJ (0.48), medium 7.98 MJ (0.22) and high 7.35 MJ (0.39) P < 0.05); however, a corresponding relationship between dietary restraint and reduced micronutrient intakes was not found. Highly restrained eaters obtained more of their energy intake from bread, fruit and cheese and less from meat, meat products and confectionery. Levels of physical activity were not significantly different between the dietary restraint groups. There was a poor relationship between reported energy intake and estimated energy expenditure. Haematological parameters of iron status were similar across the restraint groups.

CONCLUSIONS

Dietary restraint was exercised by the consumption of a "healthy eating diet". Dieting was not related to a lower iron status; however, the low dietary iron intake and poor iron status of the whole sample is of concern.

Affluent adolescent girls of Delhi: eating and weight concerns

Despite a dramatic increase in research on eating-related pathologies, gaps remain in our understanding of the factors responsible for the development and maintenance of dysfunctional attitudes and behaviour related to weight and eating among adolescents. A study was therefore conducted to compare eating and weight concerns among underweight, normal-weight and obese affluent adolescent girls in New Delhi. The sample comprised fifty underweight, fifty normal-weight and thirty obese girls, 16-18 years of age. Information was collected about their body image perception, weight concerns and eating attitudes by a well-structured questionnaire. Dietary intake was determined by 24 h recall and a food-frequency questionnaire. Body size was adjudged by measurements of weight, height, waist, hip and mid upper arm circumferences, and the BMI and waist : hip ratio were determined. Of the subjects, 99.2 % had a gynoid pattern of fat distribution. Concerns about excess weight were prevalent among the adolescent girls, even among those who were normal-weight and underweight. The level of satisfaction with body size decreased with increase in weight. Dieting behaviour was reported in a higher number of obese (76.6 %) compared with normal-weight (38 %) and underweight (14 %) girls. Of the obese girls, 43.3 % were found to be at a significantly (P=0.00109) greater risk of developing anorexia in the future. Characteristic dietary features of adolescence, such as missing meals, snacking and eating out, were observed. While the diets of most of the subjects were adequate in Ca, thiamin, riboflavin and vitamin C, they were found to be deficient in energy, protein, Fe, niacin, vitamin A and fibre. Thus, it is important to recognize that weight concerns and dissatisfaction with body size may pose a threat to a healthy nutritional state, and may develop into precursors of a later eating disturbance.

To transfuse or not to transfuse: iatrogenic compromise of women's reproductive careers

A 21-year-old Indo-Asian woman, who had arrived in the UK 5 months before presentation, consulted her general practitioner because of tiredness and shortness of breath on climbing stairs. There were no significant factors in her history, except that she did not eat red meat. Initial investigation revealed a severe anaemia with a haemoglobin (Hb) concentration of 4.6 g/dl, mean cell volume (MCV) of 49.4 fl, mean cell haemoglobin (MCH) of 11.5 pg, white cell count of 7.4 × 109/litre and a platelet count of 583 × 109/litre. She was promptly referred as an emergency to a general medical ward in a teaching hospital for further management. On admission, physical examination revealed pallor and a tachycardia of 110 beats/minute, but there ware no other significant findings. Her electrocardiogram was normal and there was no evidence of cardiac failure on chest X-ray. She was transfused three units of packed red cells. Subsequently she underwent further investigations, including Hb electrophoresis, vitamin B12 and folate levels, ferritin and transferrin levels, serum urea and electrolytes, liver function tests, blood film for malarial parasites, endomysial and gliadine antibodies, and comprehensive gastrointestinal tract work-up. All investigations were negative with the exception of a positive anti-gliadine immunoglobulin G. The diagnosis of iron deficiency anaemia of unknown cause was made. The patient was given dietary advice and was discharged back under her GP's care 6 months later, having maintained a normal Hb.

Childhood nutrition and poverty

One in three children in Britain lives in poverty (households whose income was less than 50% average earnings). Low income is associated with poor nutrition at all stages of life, from lower rates of breast-feeding to higher intakes of saturated fatty acids and lower intakes of antioxidant nutrients. Moreover, there is increasing evidence that poor nutrition in childhood is associated with both short-term and long-term adverse consequences such as poorer immune status, higher caries rates and poorer cognitive function and learning ability. These problems arise primarily because parents do not have enough money to spend on food, not because money is being spent unwisely. Policy options to improve the dietary health of poor children include: giving more money to the parents by increasing Income Support (social security) payments, providing food stamps or vouchers, and using food budget standards to inform the levels of income needed to purchase an adequate diet; feeding children directly at school (not only at lunchtime but also at breakfast or homework clubs), by providing free fruit at school, and by increasing entitlement to free food amongst children living in households with low incomes; improving access to a healthy and affordable diet by first identifying 'food deserts' and then considering with retailers and local planners how best to provide food in an economical and sustainable way. The value of using food budget standards is illustrated with data relating expenditure on food to growth in children from 'at-risk' families (on low income, overcrowded, headed by a lone parent or with four or more children under 16 years of age) living in a poor area in London. Lower levels of expenditure are strongly associated with poorer growth and health, independent of factors such as birth weight, mother's height, or risk score. The present paper provides evidence that supports the need to review Government legislation in light of nutrition-related inequalities in the health of children.

Is a vegetarian diet adequate for children

The number of people who avoid eating meat is growing, especially among young people. Benefits to health from a vegetarian diet have been reported in adults but it is not clear to what extent these benefits are due to diet or to other aspects of lifestyles. In children concern has been expressed concerning the adequacy of vegetarian diets especially with regard to growth. The risks/benefits seem to be related to the degree of restriction of he diet; anaemia is probably both the main and the most serious risk but this also applies to omnivores. Vegan diets are more likely to be associated with malnutrition, especially if the diets are the result of authoritarian dogma. Overall, lacto-ovo-vegetarian children consume diets closer to recommendations than omnivores and their pre-pubertal growth is at least as good. The simplest strategy when becoming vegetarian may involve reliance on vegetarian convenience foods which are not necessarily superior in nutritional composition. The vegetarian sector of the food industry could do more to produce foods closer to recommendations. Vegetarian diets can be, but are not necessarily, adequate for children, providing vigilance is maintained, particularly to ensure variety. Identical comments apply to omnivorous diets. Three threats to the diet of children are too much reliance on convenience foods, lack of variety and lack of exercise.

Teenage vegetarianism: prevalence, social and cognitive contexts

The aim of this study was to measure the prevalence of teenage vegetarianism and associated food habits and beliefs. Two thousand senior secondary school students (mean age 16 years), from 52 schools in South Australia, participated in a two part survey. The findings show that teenage vegetarianism is primarily a female phenomenon, ranging in prevalence, according to definition, from 8 to 37% of women and 1 to 12% of men. Support for vegetarian practices was high especially from mothers (63%) and classmates (46%). Generally, "teenage vegetarians" consumed fewer red meats than non-vegetarians but ate more chicken. They cited health, animal welfare and environmental reasons in support of their habits. The importance of operational definitions of vegetarianism is emphasized and the findings are discussed in relation to likely motivational influences.

Attitudes towards meat-eating in vegetarian and non-vegetarian teenage girls in England--an ethnographic approach

This study compared vegetarian and non-vegetarian teenage English girls' attitudes towards meat. A convenience sample of 15 vegetarian (mean age 17.2 years) and 15 non-vegetarian (mean age 17.3 years) girls was recruited from a teenage health clinic. Attitudes towards meat were assessed in a single, tape-recorded, semi-structured interview. Eight themes of the cultural meaning of meat were identified; five were common to both groups: Animal (66% of vegetarians, 33% of non-vegetarians); Taste/Texture/Smell (66%, 60%); Flesh and Blood (86%, 26%); Colour (33%, 20%); Miscellaneous (60%, 46%). The theme Eating Well was unique to the non-vegetarian group (40%). The themes Life/Death and Health-related were unique to the vegetarian group (66 and 20%, respectively). The vegetarians generally abhorred killing animals for food, meat's sensory characteristics and ingesting blood. A meat-free diet was not particularly associated with health in either group. The non-vegetarians tended to characterize meat positively, both liking meat's sensory characteristics and associating meat with luxury and special occasions. We speculate on possible reasons for the current popularity of vegetarianism in teenage girls.

The remedying of iron deficiency: what priority should it have?

Fe deficiency is considered to be the commonest of nutritional deficiencies worldwide. Adverse effects are stated to include lower growth rate and impaired cognitive scores in children and poor pregnancy outcome and lower working capacity in adults. In the present review, Fe intake, stores of the element, the magnitude of deficiencies and the benefits from interventions, as reflected in the results of clinical trials, are discussed. Because of inadequacies of knowledge in numerous respects, more information is needed regarding the extent to which clinical trials relate to public health realities, before introducing regional or national supplementation programmes. While Fe supplements are needed in certain groups, and in particular regions, increased dietary intakes could be supplied by food fortification, as well as by individual improvements in intake.

Effect of parental mental health status on adolescents' dietary behaviors

PURPOSE

The purpose of this study was to explore whether adolescents of substance-abusing and depressed parents were more likely to have poor dietary behaviors than those in the health comparison families.

METHODS

The sample consisted of 841 adolescents in families of substance-abusing parents, depressed parents, and parents without a diagnosable psychiatric disorder. All adolescents were given a food frequency questionnaire.

RESULTS

Adolescents whose parents had substance abuse disorder had lower intakes of fruits and higher intakes of high fat foods, and also ate more frequently at fast-food restaurants and purchased more snacks. Adolescents whose parents were depressed had lower intakes of all food groups. Mother's mental health status impacted more on adolescents' dietary behaviors than did the father's mental health status.

CONCLUSION

This research suggests that at-risk behaviors among youth of psychiatrically impaired parents may extend to food behaviors.

The dietary intake of a group of vegetarian children aged 7-11 years compared with matched omnivores

There is a lack of information concerning the diet of vegetarian children. The present study compared the dietary intake of fifty vegetarian children, aged 7-11 years, with fifty matched omnivores. Three 3 d food records were completed by each child at intervals of 6 months. The day after completing the record each child was interviewed to clarify food items and assess portion sizes. Food records were analysed using Microdiet (University of Salford). Finger-prick cholesterol and haemoglobin measurements were taken from a subsample of the group. Only one child's family was a member of the Vegetarian Society and almost one-third of vegetarian children had omnivorous parents (seventeen of fifty subjects). The energy intake (MJ) of the vegetarians was significantly lower than that of the omnivores, 7.6 (SD 1.05) and 8.0 (SD 1.36) respectively; there were no significant differences in Fe or fat intakes. For the vegetarians polyunsaturated:saturated fat ratio (P:S 0.7 (SD 0.04)) and NSP intake (13.8 (SD 0.7) g/d) were significantly higher than those of the omnivores (P:S 0.5 (SD 0.02), NSP 10.3 (SD 0.4) g/d). There was no significant difference in cholesterol measurements (mmol/l) between the two groups: vegetarian 3.5 (SD 0.12), omnivores 3.7 (SD 0.15). The haemoglobin level (g/l) of the vegetarians (11.8 (SD 0.2)) was significantly below that of the omnivores (12.4 (SD 0.2)); 47.5% of the vegetarian children fell below the third percentile of the Dallman reference curves (Dallman & Siimes, 1979). The intake of the vegetarians more closely resembled current recommendations (Department of Health, 1991), although they need to be as aware as omnivores of the need to reduce fat intake. The haemoglobin levels of vegetarian children suggest that they need dietary advice to ensure optimal absorption of Fe.

Prenatal screening for haemoglobin disorders

The technology has been available to detect carriers of haemoglobin disorders since the late 1960s. Prenatal diagnosis has been available since 1978. First trimester diagnosis by chorionic villus sampling and DNA analysis was introduced in 1982, and subsequent simplifications in DNA technology have made screening, counselling and prenatal diagnosis cost-effective at the community level, in countries at all levels of development. Audit of prenatal diagnosis for haemoglobin disorders in countries which have the resources and infrastructure necessary for genetic population screening (such as the UK and other European countries), has shown that the number of prenatal diagnoses actually performed fall far short of expectation. The demonstration that this reflects failures in delivering information, screening and counselling to the populations at risk, rather than rejection of prenatal diagnosis, shows the importance of placing more emphasis on the organisational and social requirements for genetic population screening. In some countries current attitudes towards abortion exclude provision of prenatal diagnosis within the health service, but in many such cases it has been set up in the private sector. It is also being introduced through combined private and charitable efforts in an increasing number of developing countries, including some with extremely limited health resources: such centres are likely to act as nuclei for emergence of genetics services in these communities. A particularly notable recent achievement is the introduction of prenatal diagnosis in Nigeria, where 1-2% of all children born suffer from sickling disorders.

Micronutrients and exercise: anti-oxidants and minerals

Exercise has been shown to increase indirect measures of lipid peroxidation. However, exercise and training appear to augment the body's anti-oxidant defence system. Whether this augmented defence system can keep up with the increase in lipid peroxidation with exercise is not known. Iron depletion is experienced by many athletes, especially female endurance athletes and adolescents, but iron deficiency anaemia is rare. Iron depletion could affect the ability to train and recover from strenuous exercise, but this has not been examined. There is a concern that female athletes, especially adolescents, are not ingesting sufficient calcium, and this may affect the development of peak bone mass and increase the risk of bone fractures. Further research is needed on mineral and trace mineral intake and loss in athletes. It appears that most athletes have adequate status of chromium, zinc, phosphate and magnesium. Athletes who are restricting energy intake to achieve a low body mass (for example, endurance runners), may not have adequate vitamin or mineral status. More data are needed on vitamin/mineral status of athletes from underdeveloped countries. The general recommendation for athletes is that foods rich in anti-oxidants and minerals should be ingested rather than supplements.