![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
*
Department of International Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322 and
UNICEF, Beijing, China 100600
4To whom correspondence should be addressed. Dept. of International Health, Emory Univ., 1518 Clifton Rd, N. E., Atlanta, GA 30322. E-mail: uramakr{at}sph.emory.edu
 |
ABSTRACT |
|---|
 TOP ABSTRACT Historical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
KEY WORDS: • iron deficiency • iron fortification • control and prevention interventions
|
Historical trends in iron deficiency |
|---|
|
TOPABSTRACTHistorical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
,2
). In contrast to many developing countries in which iron deficiency affects a large proportion of the population (30–70%), the prevalence of iron deficiency is <20% in the industrialized countries of Europe and North America (3
–5
). These lower rates are the result of the significant progress that has been made in last century. This paper examines the various factors that account for this decline with lessons that can be learned for strategies in developing countries.
Historical records show that iron deficiency and anemia were very common among women of reproductive age in many developed countries even during the late 18th and 19th centuries. Among the earliest documented references to iron deficiency are those from the 15th to 16th centuries when the term "chlorosis" was used to describe "green sickness" as a hysterical condition associated with weak blood and particularly affecting young women and adolescent girls (6
). Chlorosis was quite common in many developed countries and there were even concerns about the increase in incidence during the 19th century. At the same time, however, significant advances were made in hematology and this led to iron salts being recommended as a treatment for chlorosis. Without a doubt, these scientific advances combined with the improvements in environment and diets of women in the early 20th century most likely contributed to the disappearance of "chlorosis" in developed countries by the mid-20th century. A standard definition of anemia became available only in the 1960s (it was created by the WHO) after which estimates of the prevalence of this nutritional disorder were generated (7
). Although limited data exist on trends in the prevalence of anemia and iron deficiency using nationally representative data, there is evidence to support declines in the prevalence of iron deficiency and anemia among women and young children in many developed countries in North America and Western Europe. For example, the prevalence of anemia declined from 25% in 1963 to 1964 to 7% in 1974 to 1975 among women of reproductive age living in Goteberg, Sweden (8
). Estimates from nationally representative data based on the National Health and Nutrition Examination Surveys (NHANES)5
in the United States also show that iron deficiency declined from 21 to 13%, and from 10 to 6% among young children aged 1 to 2 y and 3 to 4 y, respectively, between 1974 to 1975 and 1989 to 1994 (9
). The reasons for these declines cannot be attributed solely to a single approach but rather to a range of factors that have occurred over time as a result of both economic development (direct and indirect) and the implementation of specific policies (for example, routine iron supplementation for pregnant women).
|
Determinants of iron status |
|---|
|
TOPABSTRACTHistorical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
. In terms of iron intake, fortified products and pharmaceutical supplements are important sources of iron, in addition to the usual diet in many developed countries; the actual amount of iron absorbed depends on iron requirements (e.g., increased during pregnancy) and the presence of inhibitors (e.g., phytates) and enhancers (e.g., ascorbic acid, animal foods) of iron absorption in the diet. On the other hand, iron is lost in sweat and during menstruation, both of which can vary significantly among individuals. Iron requirements are also increased during periods of rapid growth, such as during pregnancy, early childhood and adolescence, and significant amounts of iron can also be lost due to parasitic infections such as malaria, hookworm and schistosomiases (1
).
|
|
Iron intakes |
|---|
|
TOPABSTRACTHistorical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
). The current recommended daily allowance for iron is 18 and 27 mg/d for nonpregnant and pregnant women of reproductive age in the United States, respectively (11
). Food consumption data indicate high intakes of meat (168 g/d in 1994–1995) and citrus fruits (52 g/d) in American women, both of which can enhance iron absorption. It is noteworthy that the consumption of total grain, one of the commonly fortified foods, has increased dramatically from 177 g/d in 1977 to 1978 to 255 g/d in 1994 to 1995. In contrast, beef consumption has declined from 47 g/d in 1974 to 1975 to 19 g/d in 1994 to 1995 in American women (12
). Data from Europe also indicate adequate iron intakes from diverse sources (13
). |
Role of fortification |
|---|
|
TOPABSTRACTHistorical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
–16
). The effect of two World Wars, which created an urgent requirement to meet nutritional needs effectively, combined with advances in food technology, nutritional sciences and rapid expansion of the commercialization of food processing set the stage for enrichment and fortification in many industrialized countries. Enrichment of flour with essential nutrients, namely, vitamins and minerals such as iron to compensate for losses during processing, began as early as the 1930s in many developing countries (17
). During World War II, the U.S. Food and Drug Administration (FDA) set enrichment standards for all cereals (rice, cornmeal) as well as pasta and bread, whereas Canada permitted it only for wheat flour in 1952 [(18
), Johnson, J., IDRC, personal communication, 2001]. Elemental iron powder has been used as the fortificant especially for cereal-based products, with levels of enrichment ranging from 18 to 30 µg/g. The increased awareness of the problem of iron deficiency anemia in the 1960 to 1970s led to increases in the level of enrichment in cereals, an action supported by the United States milling industry. Similarly, many countries in Europe, especially in Scandinavia (Sweden, Denmark, Finland), also recommended increasing the amount of iron added to flour from 
30 to 60 µg/g in the 1960s (19
,20
).
The recommendations for enrichment and/or fortification differ among countries and have also evolved over time. For example, iron fortification has been mandatory for white flours, enriched pastas, enriched precooked rice and certain substitute foods in Canada since 1976,6
whereas it is voluntary at the national level and mandatory at the state level for nearly two thirds of the United States (16
). In contrast, fears of iron overload have led to the removal of fortification in Finland and Denmark (21
,22
). The key to success in fortification, however, does not rely solely on the regulatory framework but rather on successful private-public partnerships as shown in Figure 2
. For example, key private sector players in the U.S. experience include commercial food processors (millers, breakfast foods, infant food) and the pharmaceutical industry. Also involved are public health agencies such as the Centers for Disease Control and Prevention and the medical community, both private and public (universities, National Institutes for Health) and regulatory groups such as the FDA, USDA and the Department of Health and Human Services at the federal level and other state and regional bodies. Of note are the strong linkages that have existed between the research community and public health agencies, strong support for research and development in the private sector and interaction between legislators and private industry. Similar structures are in place in other industrialized countries such as Canada, United Kingdom and parts of Europe but are often lacking in developing countries due to limited resources and structural inadequacies.
|
) estimated from national food consumption data that fortified cereal contributed 10 to 20% of total iron intakes in Denmark, Finland and Sweden where iron fortification was mandated (13
). The contribution of different dietary sources of iron in selected countries in Europe is shown in Figure 3
. In their analysis of the reasons for the decline in iron deficiency among Swedish women, Hallberg and Hulthen identified increased intakes due to the consumption of fortified flour combined with reduced losses due to increased usage of oral contraceptives as the main factors (8
). As the demand and supply of processed food products have increased during the 1980s and 1990s, several vitamins and minerals such as iron have been added to an increasing array of food products especially ready-to-eat cereals. For example, a recent study shows the steady increase in the contribution of fortified foods to iron intakes of German children aged 2 to 13 y from 60% in 1987 to 78% in 1995 (23
). Nationally representative data from the United States show that in women of reproductive age, fortified ready-to-eat cereals contributed 40% of total iron intakes among consumers of these foods (24
).
|
,26
). The prevalence of anemia declined steadily from 7.8% in 1975 to 2.9% in 1984 among low income children enrolled in the WIC Program as shown in Figure 4
. Furthermore, data from Tennessee show that although socioeconomic status (SES) remained relatively stable during the same period, the prevalence of anemia declined significantly within each SES group, indicating the effect of improvements in iron nutrition. Similar reductions were also found among middle-class children during the same period based on data from pediatric clinics throughout the United States (27
).
|
|
Iron losses |
|---|
|
TOPABSTRACTHistorical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
); and 2) improvements in women’s status that has lead to delayed childbearing and fewer pregnancies. Total fertility rates have declined from about 4 during the latter half of the 19th century to about 1.8 in 2000 in North America and parts of Europe (29
). Age at first pregnancy has also increased over time along with coverage of maternal health services (prenatal and postpartum care), which is now almost universal (>90%) in most developed countries. Both mean age at first pregnancy (16–19 y) and coverage of maternal health services are much lower (30–65%) in many developing countries in which iron deficiency is common (30
). These factors are important because health services in most developed countries continue to recommend routine iron supplementation during pregnancy, a practice that began in the 1960s. Moreover, compliance with supplementation is higher than in many developing countries in which problems of supply and lack of knowledge are common (31
, 32
). For example, nationally representative data from the United States show that prenatal supplement use ranged from 60 to 85% during the 1980s (33
). It is interesting to note that 18 to 30% of women also reported preconceptual use of iron-containing supplements. Data from NHANES III also show that, overall, 25% of women of reproductive age consume iron-containing supplements, although this varies by age, race-ethnicity and SES (24
). Other factors such as the reduction of low birth weight may also contribute to the reduction of iron deficiency in infancy because iron stores of the newborn may be related to that of the mother (34
). Undoubtedly, increased intakes and reduced losses of iron have helped improve iron stores in many industrialized countries. It is also important to note that although some of these changes have occurred rapidly, others have taken more time. Thus, improvements in iron status have occurred during various stages of the life cycle for recent generations living in developed countries, which in turn have contributed to the declines in the prevalence of iron deficiency. |
Challenges |
|---|
|
TOPABSTRACTHistorical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
). Similarly, surveillance data from the Pregnancy Nutritional Surveillance System indicate that during the 1990s, the prevalence of anemia has remained around 20% and may even have increased slightly among low income pregnant women in the United States, indicating the need for constant monitoring and development of new approaches (9
). Other studies have also shown high rates of anemia among children in Alaska and Native American populations in Canada, where nearly one fourth (24%) of infants aged 9 mo are iron deficient (35
,36
).
Although historical data lead us to infer that fortified foods have increased iron intakes over time, current patterns of intake of fortified foods and/or supplements do not necessarily explain the increased risk of iron deficiency in selected subgroups. For example, data from NHANES III indicate that only 13% of women of reproductive age consume iron fortified ready-to-eat cereals and, more importantly, that the risk of iron deficiency anemia is not associated with the consumption of these foods (24
). Similarly, dietary intakes (both in terms of actual intakes and bioavailability) do not explain the differences in the prevalence of iron deficiency in Hispanic women compared with non-Hispanic Whites (10
). These findings demonstrate the need for more information about patterns of consumption of iron-containing foods as well as a better understanding of factors that may influence iron losses so that interventions can be targeted appropriately. For example, survey data indicate that consumption of iron-containing supplements in the United States is low among groups at greatest risk of iron deficiency (24
), suggesting that increased provision of iron supplements could be an appropriate intervention in these groups.
Another major challenge is that intakes may decline in some developed countries as a result of recent policies, i.e., the removal of legislation that had required fortification of flour with iron and a shift from universal to selective supplementation during pregnancy, motivated by concerns about possible adverse effects of increased iron stores. For example, fortification of flour with iron was stopped in Denmark in 1987 to 1988 and other Scandinavian countries have followed suit (22
). Although recent data from Denmark have not shown any adverse effects,7
these actions may lead to an increased risk of iron deficiency among subgroups such as young children and women of reproductive age over time and therefore require constant monitoring and evaluation (22
). The resurgence of iodine deficiency disorders due to reduced production and distribution of iodized salt following the break-up of the former Soviet Union serves as another example of the need for ongoing monitoring of nutritional status (37
). Also, as the prevalence of iron deficiency declines, another concern for industrialized countries is the need for more effective and sensitive iron status screening methods. As prevalence declines, traditional indicators, such as hemoglobin, will no longer work as effectively. Finally, improved methods for identification of women with increased iron losses is another area of need because excess iron loss is becoming a more likely cause of deficiency than inadequate iron intake.
In conclusion, significant progress has been made and the experience gained is valuable in our efforts to combat iron deficiency in developing countries in which the problem of iron deficiency and challenges to prevent it are far greater. Although few challenges remain for industrialized countries, constant vigilance and innovative approaches to combat this problem for subgroups that are at increased risk for iron deficiency even in developed countries are indeed warranted.
|
FOOTNOTES |
|---|
2 This article was commissioned by the International Life Sciences Institute Center for Health Promotion (ILSI CHP). The use of trade names and commercial sources in this document is for purposes of identification only and does not imply endorsement. In addition, the views expressed herein are those of the individual authors and/or their organizations and do not necessarily reflect those of ILSI CHP.
3 Supported by National Institutes of Health grant HD-34531.
5 Abbreviations used: FDA, United States Food and Drug Administration; NHANES, National Health and Nutrition Examination Surveys; SES, socioeconomic status; WIC, Women, Infant and Children’s Program.
6 Mandatory addition of iron to other food products such as simulated meat products, enriched rice and enriched pasta began in 1975, 1986 and 1994, respectively, in Canada.
7 Although mean serum ferritin values declined slightly, they remain high (>100 µg/L) among adult men and postmenopausal women and adequate (32 µg/L) among premenopausal women in 1994–1995.
|
LITERATURE CITED |
|---|
|
TOPABSTRACTHistorical trends in iron...Determinants of iron statusIron intakesRole of fortificationIron lossesChallengesLITERATURE CITED |
|---|
1. Allen, L. & Casterline-Sabel, J. (2001) Prevalence and causes of nutritional anemias. Ramakrishnan, U. eds. Nutritional Anemias 2001:7-22 CRC Press Boca Raton, FL. .
2. Ramakrishnan, U. (2001) Functional consequences of nutritional anemia during pregnancy and early childhood. Ramakrishnan, U. eds. Nutritional Anemias 2001:43-68 CRC Press Boca Raton, FL. .
3. World Health Organization (2000) WHO Global Database on Anemia and Iron Deficiency 2000www.who.int/nut/db-mdis.
4.
Looker, A. C., Dallman, P. R., Carroll, M. D., Gunter, E. W. & Johnson, C. L. (1997) Prevalence of iron deficiency in the United States. J. Am. Med. Assoc. 277:973-976.
5. Hallberg, L. (1995) Results of surveys to assess iron status in Europe. Nutr. Rev. 53:314-322.[Medline]
6. Guggenheim, K. Y. (1995) Chlorosis: the rise and disappearance of a nutritional disease. J. Nutr. 125:1822-1825.
7. Underwood, B. (2001) Nutritional anemias worldwide: a historical overview. Ramakrishnan, U. eds. Nutritional Anemias 2001:1-6 CRC Press Boca Raton, FL. .
8. Hallberg, L., Bengtsson, C., Garby, L., Lennartsson, J., Rossander, L. & Tibblin, E. (1979) An analysis of factors leading to a reduction in iron deficiency in Swedish women. Bull. WHO 57:947-954.[Medline]
9. U.S. Department of Health and Human Services (2000) Healthy People 2010, 2nd ed. Understanding and Improving Health and Objectives for Improving Health vols. 1 and 2 2000 DHHS Washington, DC. .
10. Ramakrishnan, U., Frith-Terhune, A., Cogswell, M. & Kettel-Khan, L. (2000) Dietary determinants of low iron stores among Mexican American and non-Hispanic white females: Third National Health and Nutrition Examination Survey, 1988–94 (NHANES III). FASEB J. 14:345.6(abs.).
11. Institute of Medicine (2001) Dietary Reference Intakes. Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, Zinc 2001 National Academy of Sciences Washington, DC. .
12. Enns, C. W., Goldman, J. D. & Cook, A. (1997) Trends in foods and nutrient intakes by adults: NFCS 1977–78, CSFII 1989–91, and CSFII 1994–95. Fam. Econ. Nutr. Rev. 10:2-15.
13. Hallberg, L. & Rossander-Hulthén, L. (1989) Prevalence of iron deficiency in European countries and attempts to analyze possible causes of differences. Bibl. Nutr. Dieta 44:94-105.
14. UNICEF (1998) Preventing Iron Deficiency in Women and Children: Background and Consensus on Key Technical Issues and Resources for Advocacy, Planning and Implementing National Programmes 1998 UNICEF/UNU/WHO/MI Technical Workshop. UNICEF New York, NY. .
15. Rees, J. M., Monsen, E. R. & Merrill, J. E. (1985) Iron fortification of infant foods. A decade of change. Clin. Pediatr. 24:707-710.
16. Walter, T., Olivares, M., Pizarro, F. & Hertrampf, E. () Fortification. Ramakrishnan, U. eds. Nutritional Anemias :153-184 CRC Press Boca Raton, FL. .
17. Ranum, P. & Johnson, Q. (2001) Manual for Flour Fortification with Iron: Technical and Operational Guidelines for the Fortification of Flour with Iron 2001 International Nutrition Foundation. Project SUSTAIN Washington DC. .
18. Park, Y. K., Miller, D. F., Yetley, E. A., Vanderveen, J. E. & Forbes, A. L. (2001) History and current status of cereal-grain products fortification in the United States. (in press) .
19. Hurrell, R. F. (1993) Prospects for improving the iron fortification of foods. Forman, S. J. Zlotnik, S. eds. Nutritional Anemias 1993 Raven Press New York. .
20. Richardson, D. P. (1990) Food fortification. Proc. Nutr. Soc. 49:39-50.[Medline]
21.
Salonen, J. Y., Nyyssonen, K., Korpela, H., Tuomilehto, J., Seppanen, R. & Salonen, R. (1992) High stored iron levels are associated with excess risk of myocardial infarction in eastern Finnish men. Circulation 86:803-811.
22. Osler, M., Milman, N. & Heitmann, B. L. (1999) Consequences of removing iron fortification of flour on iron status among Danish adults: some longitudinal observations between 1987 and 1994. Prev. Med. 29:32-36.[Medline]
23. Sichert-Hellert, W., Kersting, M., Alexy, U. & Manz, F. (2000) Ten-year trends in vitamin and mineral intake from fortified food in German children and adolescents. Eur. J. Clin. Nutr. 54:81-86.[Medline]
24. Ramakrishnan, U., Hickey, M., Kettel Khan, L. & Cogswell, M. (2001) Patterns of use of iron fortified foods among women of reproductive age in the United States. FASEB J. 15:#748.8(abs.).
25.
Yip, R., Binkin, N. J., Fleshood, L. & Trowbridge, F. L. (1987) Declining prevalence of anemia among low-income children in the United States. J. Am. Med. Assoc. 258:1619-1623.
26.
Centers for Disease Control (1986) Declining anemia prevalence among children enrolled in public nutrition and health program selected states. J. Am. Med. Assoc. 256:2165.
27.
Yip, R., Walsh, K. M., Goldfarb, M. G. & Binkin, N. J. (1987) Declining prevalence of anemia in childhood in a middle-class setting: a pediatric success story?. Pediatrics 80:330-331.
28. Martin, L. K. (1972) Hookworm in Georgia. II. Survey of intestinal helminth infections in members of rural households of southeastern Georgia. Am. J. Trop. Med. Hyg. 21:930-943.
29. Chesnais, J. C. (1992) The demographic transition: stages, patterns, and economic implications: a longitudinal study of sixty-seven countries covering the period 1720–1984. The Fertility Decline 1992:88-137 Oxford University Press New York, NY. .
30. UNICEF (2001) The State of the World’s Children 2001 2001 UNICEF House New York, NY. .
31. Centers for Disease Control and Prevention (1998) Recommendations to prevent and control iron deficiency in the United States. Morb. Mortal. Wkly Rep. 47:1-36.[Medline]
32. Yip, R. (1994) Iron deficiency: contemporary scientific issues and international programmatic approaches. J. Nutr. 124:1479S-1490S.
33.
Yu, S. M., Keppel, K. G., Singh, G. K. & Kessel, W. (1996) Preconceptional and prenatal multivitamin-mineral supplement use in the 1988 National Maternal and Infant Health Survey. Am. J. Public Health 86:240-242.
34.
Allen, L. H. (2000) Anemia and iron deficiency: effects on pregnancy outcome. Am. J. Clin. Nutr. 71(suppl. 5):1280S-1284S.
35. Petersen, K. M., Parkinson, A. J., Nobmann, E. D., Bulkow, L., Yip, R. & Mokdad, A. (1996) Iron deficiency anemia among Alaska natives may be due to fecal loss rather than inadequate intake. J. Nutr. 126:2774-2783.
36. Innis, S. M., Nelson, C. M., Wadsworth, L. D., MacLaren, I. A. & Lwanga, D. (1997) Incidence of iron-deficiency anaemia and depleted iron stores among nine-month-old infants in Vancouver, Canada. Can. J. Public Health 88:80-84.[Medline]
37. Shchepliagina, L. A. (2000) Problems of iodine deficiency prevention under present-day conditions. Gig. Sanit. 5:49-52.
This article has been cited by other articles:
|
|
 |
|
  J. M. Brotanek, J. Gosz, M. Weitzman, and G. Flores Secular Trends in the Prevalence of Iron Deficiency Among US Toddlers, 1976-2002 Arch Pediatr Adolesc Med, April 1, 2008; 162(4): 374 - 381. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. Etcheverry, K. M. Hawthorne, L. K. Liang, S. A. Abrams, and I. J. Griffin Effect of Beef and Soy Proteins on the Absorption of Non-Heme Iron and Inorganic Zinc in Children. J. Am. Coll. Nutr., February 1, 2006; 25(1): 34 - 40. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 U. Ramakrishnan Nutrition and low birth weight: from research to practice Am. J. Clinical Nutrition, January 1, 2004; 79(1): 17 - 21. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
