Stefan Sieber is a social and life course epidemiologist. He obtained his PhD in Social Epidemiology at the University of Geneva, Switzerland in 2021, and a postdoctoral position at the University of Lausanne, Switzerland. He has a strong interest in health inequalities, with his main research interests including life-course epidemiology, contextual and comparative research between countries, and longitudinal data analyses.

How did you get involved in work related to climate change and health?

I have always been interested in sustainable development in general. During my PhD, I studied the social side of sustainability, investigating the social determinants of health. One of the main concerns in this line of research is how these social determinants ‘get under the skin’, i.e. how do the socioeconomic conditions in which people live affect their health. Given that socioeconomic status influences where and how we live, it is key in determining the environment to which we are exposed (e.g. air pollution, heat, built environment). The environmental determinants of health can serve as a mechanism to explain how social factors translate into health status. The opportunity to focus my research on how social and environmental factors interact to shape health has connected me with issues to do with climate change, a topic that has far-reaching implications for health and is deeply intertwined with societal issues.

What is your main discipline or field and what unique perspective does it bring to the issue of climate change and health? 

I come from the field of social and life course epidemiology, which examines the socioeconomic conditions of individuals throughout their lives and how these affect health. The focus on socioeconomic conditions sheds light on the social inequalities in health that can be observed to varying degrees in low and high income contexts around the world. These inequalities can also be observed in relation to the impact of climate change on health, with the most vulnerable people (the socioeconomically disadvantaged, children, the elderly, women) being disproportionately affected by the adverse effects of climate change. When assessing the links between climate change and health, it is therefore crucial to take into account the impact that climate change may have on specific population groups, providing a unique opportunity to address health inequalities through climate action.

Can you give an overview on what is being done in your work package or task, and why it is important?

In general, the aim of the work package I am involved in is to quantify the health co-benefits of climate policies in Europe. Many policies that tackle climate change through a reduction of greenhouse gas emissions, such as the European Green Deal, can result in benefits for health, for example by reducing air pollution. One of the tasks focuses on modelling policy scenarios describing potential emission pathways to the year 2050. We are investigating how air pollution associated with these emission pathways affects health and will quantify the air pollution attributable burden of ill health under these policy scenarios. Assessing these health impacts will allow us to emphasise the health co-benefits of climate change mitigation policies, providing additional arguments that can be a powerful incentive for more ambitious climate action.

What role do social inequalities play in the health effects of climate change? 

Inequalities in the health effects of climate change can be observed at different levels: For example between countries, with the historically lowest emitting countries suffering most from climate change related health impacts, but also within countries, with socioeconomically disadvantaged people being more severely impacted. Research shows that susceptibility to the health impacts of climate change reflects wider social structures and inequalities, and there is a growing body of evidence outlining how marginalised and vulnerable populations are at greatest risk of climate breakdown. For example, changes in temperature, precipitation, and extreme weather events may lead to increased food insecurity and malnutrition, particularly among vulnerable populations in low-income countries. Unintended negative impacts of climate change mitigation actions can exacerbate existing inequities and deepening injustices. Policies must ensure that marginalised and vulnerable populations are protected and that unintended consequences are taken into account. It is therefore our responsibility as researchers to shed light on the groups most affected by climate change, building evidence for strong policies that not only tackle climate change but also reduce health and other inequalities.

Why is it important to look at the health effects of climate change from a social epidemiology perspective? 

Social epidemiology enables us to document how existing socio-economic disparities intersect with climate change hazards, identifying vulnerable segments of the population that bear a disproportionate burden of the health impacts of climate change. This has the potential to inform climate change mitigation and adaptation policies, allowing for policies that can be tailored to address specific needs of vulnerable groups, ensuring that climate actions not only protect the environment but also promote health equity and social justice. Designing policies that address social disparities is crucial in order to reduce the risk of opposition and to foster widespread social support. If people perceive that they will be disproportionately affected by climate policies, the risk of opposition may increase, leading to significant delays or suspension of necessary climate mitigation and adaptation measures (as seen with the ‘yellow vest’ protests in France).  In assessing the impact of climate change mitigation scenarios on health, we will focus on vulnerable groups in the population (e.g. children, the socioeconomically disadvantaged) to better understand whether health co-benefits can be expected to be unevenly distributed across the population, shedding light on the potential need to put measures in place to redress increasing inequalities.