The effect of wealth-related inequality on undernutrition in children under five

By Dr. Liji Thomas, MDFeb 13 2024Reviewed by Danielle Ellis, B.Sc.

Despite advances in medical care, children under five continue to die in large numbers because of undernutrition, directly or indirectly, in low-income countries (LIC). The role played in such deaths by disparities in access to healthcare, lack of nutrition education and awareness, and lack of affordable available foods, all driven by socioeconomic inequality, remains unexplored.

A new study in Scientific Reports examined the effect of wealth-related inequality on undernutrition in children under five in low, lower-middle, and upper-middle-income countries. 

Background

While under-5 mortality has consistently been going down worldwide for decades, large pockets exist, especially in five sub-Saharan countries, where it is not only stable but is on the rise. The primary underlying cause is likely to be malnutrition, which is worse among underprivileged communities and individuals.

The outcomes of such undernutrition include insufficient height for age (stunting), being light for age (underweight), being too thin for height (wasting), or specific vitamin and mineral deficiency diseases. Many programs focusing on this area of child health are ongoing. Yet between one in four and one in five children remain stunted, half that number are underweight, and almost one in 15 is wasted.

The prevalence of undernutrition among children shows wide variation. For instance, children in Timor, a LIC, have 50-55% prevalence of stunting, vs. 1.5-2% in Australia and other high-income countries (HIC). Similarly, in South Sudan, 22% of children show wasting, with 27-39% of children in Burundi and Sudan being underweight but <0.5% in Australia and other HIC for both measures.

Earlier research demonstrates that beyond country-specific economic status, household income is a strong determinant of child undernutrition, as would be logically assumed. The poorer the family, the less likely the children are to be properly nourished. However, the educational status of the mother, urban or rural location, and number of siblings also play a role, as do medical consultations for child illness and vaccination readiness.

The recognition that undernutrition remains rife among the poorest countries of the world, as well as that in many countries, the children of the poor fare badly in the matter of nutrition, motivated the current study. The aim is to find out how far this is true of HIC as well as countries that are less well off.

The researchers used data from survey programs conducted for demographic and health purposes between 2017 and 2022. They used measures like stunting, wasting, and underweight to evaluate undernutrition, but concentration index (CI) to identify the existence of inequality in the distribution of this outcome.

What did the study show?

The study looked at 24 countries, with over 300,000 measurements used in each of three categories: height for age, weight for age, and weight for height. The scientists found that a third of the children were stunted, one in seven was wasted, and well over a quarter were underweight. Thus, over a third of children were undernourished.

The highest proportion was from India, where almost half the measurements showed undernutrition despite its being an Upper-Middle-Income (UMI) country by the World Bank classification (2020). Ethiopia, a LIC, and Bangladesh, a Low-Middle-Income (LMI) country, followed at nearly 40% and 35%, respectively. The lowest was in Turkiye (UMIC) and Gambia (LIC), at 10% or below.

Half the countries reflected the expected fall in child nutrition with household income. In Turkiye, for instance, most undernourished children came from poor households, and there was a 22% higher chance of wasting among urban poor children vs rural poor. Exceptions to this trend were observed in Libya and Gambia, with a relatively more uniform distribution of undernutrition by economic status.

In most cases, urban children showed this differential trend more clearly than rural children. Rwandan city children who were poor were almost a fifth more likely to be stunted and 26% more likely to be underweight than poor rural children, for example. This was not the case in Albania, where no difference was perceived.

In the Maldives, the inequality in the prevalence of undernutrition was 64% when poor urban children were compared with poor rural. There was no significant male-female disparity in most countries, though earlier reports consistently indicate that female children in LMIC are at increased risk for undernutrition.

Maternal educational status was the only other factor that correlated with differences in the prevalence of undernourished children.

What are the implications?

These findings indicate that one in three of the children whose measurements were included here were undernourished across all countries, irrespective of wealth status. This agrees with earlier studies showing that undernutrition is more common among children from LIC.

The effects of inadequate nutrition in childhood are serious and may even result in death. However, they also have long-term intergenerational impacts, both socioeconomic and physical, including lower intelligence and, thus, a tendency to sink still lower in the social scale.

Within each country, too, it became apparent that poorer households fared poorly when it came to feeding their children adequately compared to richer households, with Burundi and Cameroon reporting the highest inequity. This is explained by better access to food and health services among wealthier households. Interestingly, the prevalence of stunting is only 4% in Cameroon, indicating that such measures fail to capture the severity of socioeconomic disparity in food access among children.

There is thus a “double burden of high prevalence and deep inequality mainly affecting children of disadvantaged communities.” The challenge is to target those most vulnerable to poor nutrition in any country and to reduce the disparity in this regard between rich and poor families with children.