In the present study, obese children showed a highly statistically significant higher weight, mean height, BMI, waist circumference, hip circumference, and waist to hip ratio when compared with control. Previous studies reported that BMI is a reliable and preferable measure of adiposity in children and adolescence 17,18. The waist to hip ratio may be affected by the bulk of the gluteal muscles, which may give a false impression. Therefore, waist circumference may be a better indicator of central adiposity and is associated with cardiovascular risk factors independent of BMI 19.
In the present study, the mean systolic and diastolic blood pressure was significantly higher in obese when compared with nonobese children. The relationship between obesity and hypertension was shown in previous studies and has been demonstrated in children as young as 5 years old and young adults 20,21. Obesity-related hypertension can be explained by increased peripheral resistance coupled with high cardiac output and increased sympathetic nervous system activity. Obesity increases the cardiovascular risk for hypertension and metabolic syndrome by three-fold 22.
In our study, parasitic infestations were common. As its frequency was comparable in both groups, it was unlikely to be a direct cause of ID state. On the contrary, previous studies reported that in developing countries, blood loss due to parasitic infection or malaria is a common cause of ID. This could be explained by the fact that blood loss, reduced appetite, impaired digestion, and malabsorption may be the causes of poor iron status in children suffering from intestinal parasitic infestations 23.
With regard to the physical activity among studied groups, obese children showed infrequent physical activity compared with the control group. Moreover, it is believed that much of the increase in obesity in the last 25 years has resulted from the decreased level of physical activity in everyday life 24. Lack of daily, quality physical activity in all schools is proved to be one of the causes of obesity. Furthermore, the 2008 Physical Activity Guidelines for Americans recommended at least 60 min of aerobic physical activity each day, which is not approached by our children 25.
In our study, there was no significant difference between obese and control group children in terms of the number of main meals and snacks intake; however, obese children showed significantly higher rate of intake of eating anything available, less consumption of fresh fruits, and vegetables than the control group. Obese children had higher rate of consumption of food rich in starch and junk food than the non-obese group. This came in accordance with the previous studies that reported that overfeeding with snack food with high calories is one of the reasons for the rapidly increasing prevalence of childhood obesity 26,27. Snacking between meals has risen steadily over the last two decades, with many snacks being high in fat, sugar, or both 27.
In the present study, with regard to the diet frequency pattern, there was no statistically significant differences between obese and control group children, in terms of eating animal proteins, enhancers, molasses, or in the intake of inhibitors of iron absorption as phytates (nuts and bran), polyphynon (coffee, tea, and cocoa), or milk (inhibit iron absorption). As the frequency of dietary iron intake together with iron enhancers and inhibitors were comparable in both the groups, ID could not be directly explained by dietary intake. Similar studies supported the finding that ID in obesity is not due to deficient dietary iron 5,28–31.
In our study, obese children showed statistically highly significant lower mean hematocrit, MCV, mean corpuscular hemoglobin, serum iron, and TS, and increased TIBC, when compared with control group. Obese children showed highly statistically significant higher rate of ID when compared with the control group children. Obese children are likely to have ID six times as the nonobese group (OR: 7.09, 95% CI: 3.16–15.92).
Obese and nonobese participants of the study were recruited from the same schools sharing the same culture, social class, and economic status, not representing Egypt or even Giza Governorate. The small sample size is another limitation.
For primary school children with elevated BMIs, screening for ID should be considered. Increasing the awareness of importance of physical activity and carrying out nutritional education programs is required.
There are no conflicts of interest.
1. Han JC, Lawlor DA, Kimm SY. Childhood obesity
. Lancet 2010; 375:1737–1748.
2. Baker RD, Greer FR. Diagnosis and prevention of iron deficiency
and iron-deficiency anemia in infants and young children (0–3 years of age). Pediatrics 2010; 126:1040–1050.
3. Moschonis G, Chrousos GP, Lionis C, Mougios V, Manios Y. Healthy Growth Study group. Association of total body and visceral fat mass with iron deficiency
in preadolescents: the Healthy Growth Study. Br J Nutr 2012; 108:710–719.
4. Lanzkowsky PLanzkowsky P. Iron deficiency
anemia. Manual of pediatric hematology and oncology 2010:5th ed..USA:Elsevier Academic Press;31–46.
5. Cepeda Lopez AC, Osendarp SJM, Melse Boonstra A, Aeberli I, Gonzalez Salazar F, Feskens E, et al.. Sharply higher rates of iron deficiency
in obese Mexican women and children are predicted by obesity
-related inflammation rather than by differences in dietary iron intake. Am J Clin Nutr 2011; 93:975–983.
6. Pinhas-Hamiel O, Newfield RS, Koren I, Agmon A, Lilos P, Phillip M. Greater prevalence of iron deficiency
in overweight and obese children and adolescents. Int J Obes 2003; 27:416–418.
7. Kuczmarski RJ, Ogden CL, Grummer-Strawn LM, Flegal KM, Guo SS, Wei R, et al.. CDC growth charts: United States. Adv Data 2000; 8:1–27.
8. Willett WC, Sampson L, Stampfer MJ, Rosner B, Bain C, Witschi J, et al.. Reproducibility and validity of a semiquantitative food frequency questionnaire. Am J Epidemiol 1985; 122:51–65.
10. Bain BJ, Lewis SM, Bates ILewis SM, Bain BJ, Bates I. Basic haematological techniques. Dacie and Lewis practical haematology 2006:10th ed..London:Churchill Livingstone Elsevier;25–57.
11. Fairbanks VF, Klee GGBurtis CA, Ashwood ER. Biochemical aspects of hematology. Tietz textbook of clinical chemistry 1999:3rd ed..Philadelphia:WB Saunders Company;1642–1710.
12. Beutler ELichtman M, Kipps T, Seligsohn U, Kaushansky K, Prchal J. Disorders of iron metabolism. Williams hematology 2010:8th ed..New York:McGraw-Hill Professional;141–160.
13. Colenbrander HJ, Vink CLJ. Some aspects of the determination of serum iron
and total iron-binding capacity with teepol. Clin Chim Acta 1970; 28:175–184.
14. Dallman PRNathan DG, Orkin SH. Iron deficiency
and related nutritional anemias. Nathan and Oski’s hematology of infancy and childhood 1987.Philadelphia:WB Saunders;274–314.
15. Lewis SMLewis SM, Brain BJ, Bates I. Reference ranges and normal values. Chapter 2. Dacie and Lewis practical haematology 2006:10th ed..London:Churchill Livingstone Elsevier;11–24.
17. Pietrobelli A, Faith MS, Allison DB, Gallagher D, Chiumello G, Heymsfield SB. Body mass index as a measure of adiposity among children and adolescents: a validation study. J Pediatr 1998; 132:204–210.
18. Salem MA, El Sayed MH, Awad AH. Anthropometric assessment of infants of diabetic mothers. Egypt J Pediatr 1995; 123–4383–392.
19. Zhu S, Wang Z, Heshka S, Heo M, Faith MS, Heymsfield SB. Waist circumference and obesity
-associated risk factors among whites in the third National Health and Nutrition Examination Survey: clinical action thresholds. Am J Clin Nutr 2002; 76:743–749.
20. Sorof JM, Lai D, Turner J, Poffenbarger T, Portman RJ. Overweight, ethnicity and the prevalence of hypertension in school-aged children
. Pediatrics 2004; 1133 I475–482.
21. Moafi A, Rahgozar S, Ghias M, Ahar EV, Borumand A, Sabbaghi A, et al.. A study on body mass index, blood pressure, and red blood cell indices in new entering students of the University of Isfahan. Int J Prev Med 2011; 2:280–285.
22. Chiolero A, Madeleine G, Gabriel A, Burnier M, Paccaud F, Bovet P. Prevalence of elevated blood pressure and association with overweight in children of a rapidly developing country. J Hum Hypertens 2007; 21:120–127.
23. Ngui R, Lim YAL, Kin LC, Chuen CS, Jaffar S. Association between anaemia, iron deficiency
anaemia, neglected parasitic infections and socioeconomic factors in rural children of West Malaysia. PLoS Negl Trop Dis 2012; 6: e1550 Article no. e1550. DOI: 10.1371/journal.pntd.0001550.
24. Centers for Disease Control and Prevention. State indicator report on physical activity, 2010 2010.Atlanta, GA:US Department of Health and Human ServicesAvailable at: http://www.cdc.gov/physicalactivity/
25. US Department of Health and Human Services. 2008 Physical Activity Guidelines for Americans 2008.Hyattsville, MD:US Department of Health and Human ServicesAvailable at: http://www.health.gov/paguidelines
26. Anderson PM, Butcher KF. Childhood obesity
: trends and potential causes. Future Child 2006; 16:19–45.
27. Johnson L, Mander AP, Jones LR, Emmett PM, Jebb SA. Energy-dense, low-fiber, high-fat dietary pattern is associated with increased fatness in childhood. Am J Clin Nutr 2008; 87:846–854.
28. Reedy J, Krebs-Smith SM. Dietary sources of energy, solid fats and added sugars among children and adolescents in the United States. J Am Diet Assoc 2010; 110:1477–1484.
29. Menzie CM, Yanoff LB, Denkinger BI, McHugh T, Sebring NG, Calis KA, Yanovski JA. Obesity
-related hypoferremia is not explained by differences in reported intake of heme and nonheme iron or intake of dietary factors that can affect iron absorption. J Am Diet Assoc 2008; 108:145–148.
30. Aeberli I, Hurrell RF, Zimmermann MB. Overweight children have higher circulating hepcidin concentrations and lower iron status but have dietary iron intakes and bioavailability comparable with normal weight children. Int J Obes 2009; 33:1111–1117.
31. Tussing Humphreys LM, Liang H, Nemeth E, Freels S, Braunschweig CA. Excess adiposity, inflammation and iron-deficiency in female adolescents. J Am Diet Assoc 2009; 109:297–302.
32. Manios Y, Moschonis G, Chrousos GP, Lionis C, Mougios V, Kantilafti M, et al.. The double burden of obesity
and iron deficiency
on children and adolescents in Greece: the Healthy Growth Study. J Hum Nutr Diet 2013; 26:470–478.
33. McClung JP, Karl JP. Iron deficiency
: the contribution of inflammation and diminished iron absorption. Nutr Rev 2009; 67:100–104.
34. Baumgartner J, Smuts CM, Aeberli I, Malan L, Tjalsma H, Zimmermann MB. Overweight impairs efficacy of iron supplementation in iron-deficient South African children: a randomized controlled intervention. Int J Obes 2013; 37:24–30.
35. Del Giudice EM, Santoro N, Amato A, Brienza C, Calabrò P, Wiegerinck ET, et al.. Hepcidin in obese children as a potential mediator of the association between obesity
and iron deficiency
. J Clin Endocrinol Metab 2009; 94:5102–5107.
36. Hamza RT, Hamed AI, Kharshoum RR. Iron homeostasis and serum hepcidin-25 levels in obese children and adolescents: relation to body mass index. Horm Res Paediatr 2013; 80:11–17.
37. Amato A, Santoro N, Calabrò P, Grandone A, Swinkels DW, Perrone L, et al.. Effect of body mass index reduction on serum hepcidin levels and iron status in obese children. Int J Obes 2010; 34:1772–1774.
38. Nead KG, Halterman JS, Kaczorowski JM, Auinger P, Weitzman M. Overweight children and adolescents: a risk group for iron deficiency
. Pediatrics 2004; 114:104–108.
39. Lesperance L, Wu AC, Bernstein H. Putting a dent in iron deficiency
. Contemp Pediatr 2002; 19:60–79.
40. Wisse BE. The inflammatory syndrome: the role of adipose tissue cytokines in metabolic disorders linked to obesity
. J Am Soc Nephrol 2004; 15:2792–2800.