The silent toll of extreme heat on child growth in Bangladesh

The Climate-Stunting Connection

Bangladesh has made remarkable progress in reducing childhood stunting, bringing rates down from 42 percent in 2012 to 28 percent in 2019. However, progress has slowed, and a new, less understood threat is emerging – climate change. Could the warming planet be erasing years of success?

A recent study, Extreme heat exposure in the first 1000 days: Implications for childhood stunting in Bangladesh, has established link between extreme heat exposure in the first 1,000 days of life—from pregnancy to a child’s second birthday—and childhood stunting.

Extreme heat, defined as temperatures exceeding typical variations compared to the preceding 20 years, has a profound impact on child growth. Even a 1percent increase in extreme heat days raises the odds of stunting by 56 percent, with exposure after birth having an even stronger effect than in utero exposure – 67 percent compared to 28 percent.

This is the first study from Bangladesh to provide direct evidence that rising temperatures could be undermining decades of progress in child health and nutrition. This is the first study from Bangladesh to provide direct evidence that rising temperatures could be undermining decades of progress in child health and nutrition.

How Heat Affects Child Growth

Extreme heat isn’t just uncomfortable—it disrupts biological processes essential for development. Babies born to mothers exposed to high temperatures during pregnancy face reduced oxygen and nutrient supply, leading to low birth weight and preterm birth, both of which increase the risk of stunting. Infants and young children who struggle to regulate their body temperature suffer from higher energy needs and reduced appetite, making them more vulnerable to undernutrition. At the same time, extreme heat increases diarrhea-related diseases, which prevent proper nutrient absorption and worsen the effects of undernutrition.

Bangladesh is already one of the most climate-vulnerable countries in the world, with rising temperatures and more frequent heat waves threatening long-term child health. If trends continue, the number of extreme heat days could increase by 33 percent by 2050, making the challenge even greater.

A Global Wake-Up Call

The impact of heat on child growth is not unique to Bangladesh. In West Africa, researchers found that a 2°C rise in average temperature was linked to a 7.4 percent increase in stunting prevalence.

Climate change is no longer just an environmental crisis—it is a direct threat to child health, wellbeing, and human potential.

What Needs to Be Done?

Addressing climate-driven stunting requires urgent action across multiple sectors. Health programs need to integrate heat resilience strategies, including training healthcare workers to manage heat-related risks for pregnant women and infants. Expanding access to safe drinking water, and hydration programs in high-risk areas can help mitigate the worst effects of extreme heat.

Breastfeeding support initiatives should be prioritized, as maternal dehydration and heat stress can reduce breast milk production. Food security programs need to be strengthened to ensure nutritious diets for mothers and young children during heat waves. Investing in climate-smart agriculture will be critical to maintaining food supplies in the face of rising temperatures.

At the same time, social protection measures like cash transfers and food assistance can help families cope with economic losses caused by climate shocks. Moreover, development of early warning systems for extreme heat should be prioritized, allowing communities to prepare for extreme temperature spikes before they happen.

The Bottom Line

Bangladesh has overcome major public health challenges before, but climate change presents a new frontier. If action is not taken now, millions of children could suffer from poor growth, reduced cognitive abilities, and lifelong economic disadvantages. Bangladesh has overcome major public health challenges before, but climate change presents a new frontier. If action is not taken now, millions of children could suffer from poor growth, reduced cognitive abilities, and lifelong economic disadvantages.

The time to act is not in the future—it’s now. Governments, policymakers, and civil society must prioritize climate resilience in maternal and child health strategies to ensure that Bangladesh’s children do not pay the price of a warming world.

By addressing this challenge today, we can protect future generations and safeguard the progress Bangladesh has worked hard to achieve.

Source: blogs.worldbank