Nutritional Deficiencies

Iron - updated: 17 November 2008

Iron intake and iron status among adults in the Netherlands

Eur J Clin Nutr. 1997 Nov;51 Suppl 3:S51-8

Brussaard JH, Brants HA, Bouman M, Löwik MR.

OBJECTIVE: To assess the adequacy of iron intake and status, the prevalence of marginal iron status, the physiological and lifestyle factors influencing iron status and the role of dietary factors affecting the bioavailability of iron among Dutch adults. DESIGN: Food consumption was measured with 3 d diet records. Iron status and prevalence of iron deficiency and iron accumulation were evaluated using different criteria. Physical, biochemical and lifestyle characteristics were determined and relationships with iron status were evaluated by bi- and multivariate regression analysis. SUBJECTS: A sample of 444 adults, aged 20-79 y stratified for sex and 10 y age classes, with an overrepresentation of people with a low habitual intake of vitamin B6. RESULTS: Average iron intake was higher than the recommended daily allowance for the Netherlands in all sex-age groups except women aged 20-49, in which group average iron intake was 23% below the recommendation. Early iron deficiency, as reflected in low ferritin levels, was not found among men aged 20-49, but was observed in 5% of women aged 50-79, 11% of men aged 50-79, and 16% of women aged 20-49. Iron deficiency anaemia as reflected in low haemoglobin levels was found in 0-5% of the age-sex groups. Among men and women, 16% and 13% of variance in haemoglobin level, respectively, could be explained by physiological and dietary factors. For ferritin, the proportions were 36% and 34%, respectively. Iron status was correlated negatively with the vegetable fraction of the diet, and positively with factors from the animal fraction (haem iron, animal protein, meat). Further, haemoglobin was positively correlated with body weight among men, and with both age and use of oral contraceptives among women. Both among men and women, blood donorship in the six months prior to the study was negatively associated with serum ferritin levels. CONCLUSIONS: Women aged 20-49 are the adult sex-age group with the greatest risk of developing (an early stage of) iron depletion. The most important dietary factors influencing the iron status are the type of iron (haem/non-haem) and factors affecting the bioavailability of iron.

Publication Types:

• Study

Minerals and trace elements in total diets in The Netherlands

Br J Nutr. 1989 Jan;61(1):7-15

van Dokkum W, de Vos RH, Muys T, Wesstra JA.

1. During a period of 2.5 years, every 3 months 221 different food items forming a 'market basket' were purchased, prepared and divided into twenty-three food-commodity groups. The 'market basket' was based on a study of the dietary intake of 18-year-old male, Dutch adolescents. In the (homogenized) food groups various minerals and trace elements were determined. 2. The mean daily amounts of cadmium (21 micrograms), mercury (0.7 micrograms), lead (32 micrograms), tin (0.65 mg), arsenic (38 micrograms) and bromine (8 mg) in the diet of adolescents, as calculated from the concentrations analysed in the food groups, were all (well) below the Food and Agriculture Organization/World Health Organization acceptable daily intake (ADI) value (Codex Alimentarius Commission, 1984). 3. The mean daily amounts of zinc (14 mg) and selenium (72 micrograms) seemed to be adequate compared with the Dutch recommendations, (Voedingsraad (Dutch Nutrition Council) 1986). The amounts of copper (mean value 1.5 mg/d) and iron (mean value 14 mg/d) in the total diet were marginal. Contents of calcium (1340 mg/d), magnesium (433 mg/d) and iodine (402 micrograms/d) were all well above the Dutch recommendations for male adolescents. Sodium intake, corresponding to 11 g sodium chloride/d, was higher than advised. 4. It is concluded that the amounts of As, Br and toxic heavy metals in Dutch total-diet samples of male adolescents are of little concern as regards health aspects. Among the essential trace elements, Fe and Cu contents seem to be marginal. Some concern regarding the salt content is indicated.

Publication Types:

• Study

Iron intake in relation to diet and iron status of young adult women

Ann Nutr Metab. 2007;51(2):172-81.

Pynaert I, Delanghe J, Temmerman M, De Henauw S.

AIMS: To determine the iron intake and food sources of iron in young adult women and to compare women with high versus low iron intake on diet and iron status. METHODS: Iron intake and food sources were assessed by a 2-day estimated food record. Iron status was determined by a fasting venous blood sample. Differences in diet and iron status between women with high versus low iron intake were examined by comparing women of the fourth respectively first quartile of total iron intake (mg/day). RESULTS: The median total, heme and non-heme iron intake was 10.6, 0.6 and 9.8 mg/day, respectively. The median iron intake was 93 and 131% of the estimated average requirement (EAR) of the UK (11.4 mg/day) and USA (8.1 mg/day), respectively. The most important iron intake contributors were cereals and cereal products (31%), meat and meat products (12%) and vegetables (10%). Women with a high iron intake showed a significantly higher energy-adjusted intake of alcoholic beverages and soups and a lower intake of non-alcoholic beverages than women with a low iron intake. Approximately 5% of the women had anemia, of which 3% had iron deficiency anemia (IDA). Almost 20% was iron-deficient non-anemic. In this regard, no significant differences were found between the iron intake quartiles. CONCLUSION: The median iron intake in this study population is considerably below the national recommended dietary allowance (20 mg/day). However, based on the approach of the Dietary Guidelines Advisory Committee, iron intake seems to pose no major health problem when using the EAR as a reference. The number of women with IDA was indeed not alarming (3%), although 20% was iron-deficient non-anemic. The question remains whether an increase in iron intake can improve iron status.

Publication Types:

• Study

Iron intake and dietary sources of iron in Flemish adolescents

Eur J Clin Nutr. 2005 Jul;59(7):826-34

Pynaert I, Matthys C, Bellemans M, De Maeyer M, De Henauw S, De Backer G.

OBJECTIVE: To investigate the dietary iron intake and food sources of iron in Flemish adolescents. DESIGN: Cross-sectional survey; dietary assessment method: a 7-day estimated food record. SETTING: Private and public secondary schools in Ghent, a city in the Dutch-speaking part of Belgium. SUBJECTS: A total of 341 adolescents (129 boys and 212 girls), 13-18 y, randomly selected by a multistage clustered sampling technique. RESULTS: The mean total iron intake (s.d.) for boys was 13.4 (+/- 2.91) mg/day and for girls 10.1 (+/- 2.79) mg/day. A proportion of 38.8% of the boys and 99.5% of the girls had a mean total iron intake below the Belgian Recommended Dietary Allowance and 3.1% of the boys and 71.2% of the girls below the British Estimated Average Requirement. When bioavailable iron intake is considered, 84.5% of the boys and only 16.5% of the girls met the age-specific requirement. The food groups with the highest mean proportional contribution to total iron intake in both males and females were bread, meat and meat products, cereals and potatoes. A comparison of adolescents from the highest tertile of iron intake (mg/day) with adolescents from the lowest tertile showed a significantly higher energy-adjusted intake of brown bread and a significantly lower intake of soft drinks in the former group in both boys and girls. A significantly higher energy-adjusted intake of breakfast cereals in adolescents of the highest tertile than those of the lowest tertile was seen in girls only. Analyses in consumers only did not change this overall picture. CONCLUSIONS: One can conclude that the mean iron intake of Flemish girls is considerably lower than the current recommendations. An increased iron intake in this subgroup of the population is therefore advisable

Publication Types:

• Study

Iron deficiency in Europe

Public Health Nutr. 2001 Apr;4(2B):537-45

Hercberg S, Preziosi P, Galan P.

In Europe, iron deficiency is considered to be one of the main nutritional deficiency disorders affecting large fractions of the population, particularly such physiological groups as children, menstruating women and pregnant women. Some factors such as type of contraception in women, blood donation or minor pathological blood loss (haemorrhoids, gynaecological bleeding...) considerably increase the difficulty of covering iron needs. Moreover, women, especially adolescents consuming low-energy diets, vegetarians and vegans are at high risk of iron deficiency. Although there is no evidence that an absence of iron stores has any adverse consequences, it does indicate that iron nutrition is borderline, since any further reduction in body iron is associated with a decrease in the level of functional compounds such as haemoglobin. The prevalence of iron-deficient anaemia has slightly decreased in infants and menstruating women. Some positive factors may have contributed to reducing the prevalence of iron-deficiency anaemia in some groups of population: the use of iron-fortified formulas and iron-fortified cereals; the use of oral contraceptives and increased enrichment of iron in several countries; and the use of iron supplements during pregnancy in some European countries. It is possible to prevent and control iron deficiency by counseling individuals and families about sound iron nutrition during infancy and beyond, and about iron supplementation during pregnancy, by screening persons on the basis of their risk for iron deficiency, and by treating and following up persons with presumptive iron deficiency. This may help to reduce manifestations of iron deficiency and thus improve public health. Evidence linking iron status with risk of cardiovascular disease or cancer is unconvincing and does not justify changes in food fortification or medical practice, particularly because the benefits of assuring adequate iron intake during growth and development are well established. But stronger evidence is needed before rejecting the hypothesis that greater iron stores increase the incidence of CVD or cancer. At present, currently available data do not support radical changes in dietary recommendations. They include all means for increasing the content of dietary factors enhancing iron absorption or reducing the content of factors inhibiting iron absorption. Increased knowledge and increased information about factors may be important tools in the prevention of iron deficiency in Europe.

Publication Types:

• Review

Publication Types:

• Review