letter in reply

Oman Medical Journal [2023], Vol. 38, No. 5: e563 

The World Health Organization Body Mass Index Curves for Iranian Children

Munn-Sann Lye1, Mehran Zarghami2,3 and Fatemeh Abdollahi4*

1Formerly Department of Community of Health, Faculty of Medicine and Health Sciences, University Putra Malaysia, Serdang, Malaysia

2Department of Psychiatry, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran

3Psychiatry and Behavioral Sciences Research Center, Addiction Institute, Mazandaran University of Medical Sciences, Sari, Iran

4Department of Public Health, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran

article info

Dear Editor,

I am writing in response to a letter that was published in your valuable journal regarding our publication.1 Firstly, we would like to express our gratitude to Al-Mendalawi for his valuable time in reviewing our paper and providing insightful comments.2 The central concern raised was about the appropriateness of using the World Health Organization (WHO) body mass index (BMI) curves, specifically for Iranian children. The author noted that there are locally derived BMI curves for Iranian children with key centiles and national cut-offs based on a specific Iranian research study.3

Various growth charts have been developed using national or international samples in studies conducted by different organizations with diverse populations.4 The most significant and widely used growth charts include those devised by the WHO in 2006/2007, the Centers for Disease Control and Prevention in 2000, and the International Obesity Task Force in 2012.5,6

It is worth mentioning that numerous Iranian studies have employed the WHO BMI-z score or other international growth charts to assess children’s growth across different age groups.7 The WHO-BMI growth charts are officially endorsed by the Iranian Ministry of Health and Education and are utilized for evaluating child growth in Public Health Centers across the country.8

The author of the letter referenced a specific study conducted on a research basis3, and it is important to note that the database from this study has not yet received official endorsement from the Iranian Ministry of Health or Education. Furthermore, the BMI-z scores in this study were limited to children and adolescents aged 6-18 years, whereas our paper included analysis of infants at birth and one year of age. Additionally, their findings indicated that the BMI curves for children closely aligned with the WHO BMI curves, except for the fifth percentile, which was lower in Iranian children.3

In conclusion, while we acknowledge the importance of utilizing in-country standards, it is essential to highlight that Iranian Health Centers, along with numerous studies and publications both in Iran and globally, have consistently employed WHO BMI-z scores for age in assessing children’s growth.


  1. Al-Mendalawi MD. Impact of intimate partner violence on Iranian children’s growth and development: a descriptive-analytical study. Oman Med J 2023 Sep;38(5):e562.
  2. Lye M-S, Zarghami M, Charati JY, Abdollahi F. Impact of intimate partner violence on Iranian children’s growth and development: a descriptive-analytical study. Oman Med J 2023 Jan;38(1):e464.
  3. Mohammadi MR, Mostafavi S-A, Hooshyari Z, Khaleghi A, Ahmadi N, Kamali K, et al. National growth charts for BMI among Iranian children and adolescents in comparison with the WHO and CDC curves. Child Obes 2020 Jan;16(1):34-43.
  4. Oliveira MH, Pereira DD, Melo DS, Silva JC, Conde WL. Accuracy of international growth charts to assess nutritional status in children and adolescents: a systematic review. Rev Paul Pediatr 2022 Apr;40:e2021016.
  5. Ogden CL, Kuczmarski RJ, Flegal KM, Mei Z, Guo S, Wei R, et al. Centers for disease control and prevention 2000 growth charts for the United States: improvements to the 1977 National Center for Health Statistics version. Pediatrics 2002 Jan;109(1):45-60.
  6. World Health Organizaiton. WHO child growth standards: length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age: methods and development. 2006 [cited 2019 August 10]. Available from: https://www.who.int/publications/i/item/924154693X.
  7. Akbari H, Mohammadi M. The prevalence of obesity in Iranian children: a systematic review and meta-analysis. J Pediatr Rev 2022;10(2):93-102.
  8. Iranian Ministry of Health and Education DoP. Family and School Health - Children’s Health Department. Integrated Care of the Healthy Child. Ghom. Iran: Andisheh Mandegar; 2020.