Infant formula consumption is positively correlated with wealth, within and between countries: a multi-country study

Background
In contrast with the ample literature on within- and between-country inequalities in breastfeeding practices, there are no multi-country analyses of socioeconomic disparities in breastmilk substitute (BMS) consumption in low- and middle-income countries (LMICs).

Objective
This study aimed to investigate between- and within-country socioeconomic inequalities in breastfeeding and BMS consumption in LMICs.

Methods
We examined data from the Demographic Health Surveys and Multiple Indicator Cluster Surveys conducted in 90 LMICs since 2010 to calculate Pearson correlation coefficients between infant feeding indicators and per capita gross domestic product (GDP). Within-country inequalities in exclusive breastfeeding, intake of formula or other types of nonhuman milk (cow/goat) were studied for infants aged 0–5 mo, and for continued breastfeeding at ages 12–15 mo through graphical presentation of coverage wealth quintiles.

Results
Between-country analyses showed that log GDP was inversely correlated with exclusive (r = −0.37, P < 0.001) and continued breastfeeding (r = −0.74, P < 0.0001), and was positively correlated with formula intake (r = 0.70, P < 0.0001). Continued breastfeeding was inversely correlated with formula (r = −0.79, P < 0.0001), and was less strongly correlated with the intake of other types of nonhuman milk (r = −0.40, P < 0.001). Within-country analyses showed that 69 out of 89 did not have significant disparities in exclusive breastfeeding. Continued breastfeeding was significantly higher in children belonging to the poorest 20% of households compared with the wealthiest 20% in 40 countries (by ∼30 percentage points on average), whereas formula feeding was more common in the wealthiest group in 59 countries.

Conclusions
BMS intake is positively associated with GDP and negatively associated with continued breastfeeding in LMICs. In most countries, BMS intake is positively associated with family wealth, and will likely become more widespread as countries develop. Urgent action is needed to protect, promote, and support breastfeeding in all income groups and to reduce the intake of BMS, in light of the hazards associated with their use.