Boys are more likely to be undernourished than girls: a systematic review and meta-analysis of sex differences in undernutrition

Susan Thurstans; Charles Opondo; Andrew Seal; Jonathan Wells; Tanya Khara; Carmel Dolan; André Briend; Mark Myatt; Michel Garenne; Rebecca Sear; Marko Kerac

doi:10.1136/bmjgh-2020-004030

Boys are more likely to be undernourished than girls: a systematic review and meta-analysis of sex differences in undernutrition

BMJ Glob Health. 2020 Dec;5(12):e004030. doi: 10.1136/bmjgh-2020-004030.

Authors

Susan Thurstans¹, Charles Opondo^{2

3}, Andrew Seal⁴, Jonathan Wells⁵, Tanya Khara⁶, Carmel Dolan⁶, André Briend^{7

8}, Mark Myatt⁹, Michel Garenne^{10

11

12

13}, Rebecca Sear¹⁴, Marko Kerac^{14

15}

Affiliations

¹ Department of Population Health, London School of Hygiene and Tropical Medicine, London, UK susan.thurstans@lshtm.ac.uk.
² Department of Medical Statistics, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
³ National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK.
⁴ Institute for Global Health, University College London, London, UK.
⁵ Great Ormond Street Institute of Child Health, University College London, London, UK.
⁶ Emergency Nutrition Network, Kidlington, Oxfordshire, UK.
⁷ Department of Nutrition, Exercise and Sports, University of Copenhagen, Kobenhavn, Denmark.
⁸ School of Medicine, Center for Child Health Research.
⁹ Brixton Health, Llwyngwril, Gwynedd, UK.
¹⁰ Institut de Recherche pour le Développement, UMI Résiliences, Bondy, France.
¹¹ Institut Pasteur, Epidémiologie des Maladies Emergentes, Paris, France.
¹² FERDI, Université d'Auvergne, Clermont-Ferrand, France.
¹³ MRC/Wits Rural Public Health and Health Transitions Research Unit, School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
¹⁴ Department of Population Health, London School of Hygiene and Tropical Medicine, London, UK.
¹⁵ Centre for MARCH (Maternal, Adolescent & Reproductive Child Health), London School of Hygiene and Tropical Medicine, London, UK.

Abstract

Background: Excess male morbidity and mortality is well recognised in neonatal medicine and infant health. In contrast, within global nutrition, it is commonly assumed that girls are more at risk of experiencing undernutrition. We aimed to explore evidence for any male/female differences in child undernutrition using anthropometric case definitions and the reasons for differences observed.

Methods: We searched: Medline, Embase, Global health, Popline and Cochrane databases with no time limits applied. Eligible studies focused on children aged 0-59 months affected by undernutrition where sex was reported. In the meta-analysis, undernutrition-specific estimates were examined separately for wasting, stunting and underweight using a random-effects model.

Results: 74 studies were identified: 44/74 studies were included in the meta-analysis. In 20 which examined wasting, boys had higher odds of being wasted than girls (pooled OR 1.26, 95% CI 1.13 to 1.40). 38 examined stunting: boys had higher odds of stunting than girls (pooled OR 1.29 95% CI 1.22 to 1.37). 23 explored underweight: boys had higher odds of being underweight than girls (pooled OR 1.14, 95% CI 1.02 to 1.26). There was some limited evidence that the female advantage, indicated by a lower risk of stunting and underweight, was weaker in South Asia than other parts of the world. 43/74 (58%) studies discussed possible reasons for boy/girl differences; 10/74 (14%) cited studies with similar findings with no further discussion; 21/74 (28%) had no sex difference discussion. 6/43 studies (14%) postulated biological causes, 21/43 (49%) social causes and 16/43 (37%) to a combination.

Conclusion: Our review indicates that undernutrition in children under 5 is more likely to affect boys than girls, though the magnitude of these differences varies and is more pronounced in some contexts than others. Future research should further explore reasons for these differences and implications for nutrition policy and practice.

Keywords: child health; nutrition; public health; systematic review.

Publication types

Meta-Analysis
Research Support, Non-U.S. Gov't
Systematic Review

MeSH terms

Child
Child Nutrition Disorders*
Female
Growth Disorders
Humans
Infant
Infant, Newborn
Male
Malnutrition* / epidemiology
Sex Characteristics
Wasting Syndrome*