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

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 76 studies were identified: 46/76 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 1.13-1.40). 39 examined stunting: boys had higher odds of stunting than girls (pooled OR 1.31 95% CI 1.24-1.39). 25 explored underweight: boys had higher odds of being underweight than girls (pooled OR 1.19, 95% CI 1.07-1.32). There was some limited evidence that the female advantage indicating lower risk of stunting and underweight was weaker in South Asia than other parts of the world. 44/76 (58%) of studies discussed possible reasons for boy/girl differences; 11/76 (14%) cited studies with similar findings with no further discussion; 21/76 (28%) had no sex difference discussion. 6/44 studies (14%) postulated biological causes, 21/44 (48%) social causes and 17/44 (38%) 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.

Severe malnutrition or famine exposure in childhood and cardiometabolic non-communicable disease later in life: a systematic review

“… 89 Another explanation might be healthy survivor effect in boys as a recent review found that they are biologically more vulnerable to malnutrition and potentially only the healthiest survived. 90 …”

Differences in maternal and early child nutritional status by offspring sex in lowland Nepal

“…p-values were ≥ .05 for all other coefficients plotted. A table of regression results including sample sizes (n) is provided in Table S6 Sex differences in undernutrition have been widely reported in low and middle-income countries (Andersen et al, 2013;Martorell & Zongrone, 2012;Schoenbuchner et al, 2019;Thurstans et al, 2020;Victora et al, 2008;Wamani et al, 2007;Young et al, 2018). Examination of the 2016 (Ministry of Health Nepal, New ERA, & ICF, 2017) Nepal DHS survey shows that, as in our study, stunting prevalence was generally higher in boys than girls.…”

“…Using this approach, numerous recent studies have shown higher rates of boys being categorized as wasted (low weight-for-height) or stunted (low height-for-age) (Goncalves et al, 2019;Schoenbuchner et al, 2019;Thurstans et al, 2020), though differences of lower magnitude have been reported in India (Mukhopadhyay, 2016). A recent review of 76 studies in children aged 0 to 59 months found that stunting, wasting, and underweight were more common in boys than in girls; these differences tended to be lower in South Asian populations, which might indicate cultural preferences favoring sons (Thurstans et al, 2020). However, we found no studies that have tracked how sex differences manifest in mothers and children over time-from pregnancy, birth, and early childhood.…”

The Nutritional Status of Individuals Adopted Internationally as Children: A Systematic Review

“…This is an important area of international adoption research considering the growing evidence that suggests that CAI are at higher risk of developing precocious puberty [ 69 ]. Teilmann et al followed CAI during 39,978 person-years at risk and reported 45 girls and six boys developed precocious puberty; girls adopted internationally had a 10 to 20 times greater risk of developing precocious puberty compared to girls who had a Danish background [ 69 ]. The earlier pubertal maturation has been hypothesized to be caused by the stressful psychosocial factors which adoptees experience during infancy.…”