Making planetary health a truly interdisciplinary field

The term planetary health, and what falls within that field, provokes strong and interesting debate. Where consensus can be found is in the notion that planetary health is cross-disciplinary – involving academics from different disciplines working collaboratively on a common problem – complex and interconnected. It needs input from many academic disciplines, and many academics, each of whom needs to look outside of their own immediate area of research to wider issues that intersect, require trade-offs and involve compromises. This will enable the field to move towards being truly interdisciplinary. Only then will the right action be identified and taken.

For this reason, the planetary health programme at the Oxford Martin School recently convened the first of what is hoped to be a series of seminars open to all members of the university – regardless of faculty, discipline or field – who are intrigued by the concept of planetary health and keen to discover what their research may have to offer.

At the inaugural meeting, invited researchers from University of Oxford’s Climate Econometrics, the Environmental Change Institute, Primary Care Health Sciences, the Smith School of Enterprise and the Environment, the Future of Humanity Institute and Faculty of History joined the Oxford Martin School-based staff of The Rockefeller Foundation Economic Council on Planetary Health Secretariat to hear about the project’s progress so far, plans for the future and opportunities for collaboration.

Discussions highlighted the importance of working across different levels of magnitude – with the macro-level needing to be informed by an accumulation and magnification of (more) micro-level studies whose synthesis will inform the bigger picture. A presently incomplete picture, with diverse data sets, must not be allowed to impede progress towards a better future. Sectors, as well as geographic locations, need to be considered on a global level. The shipping sector, for instance, may be a better target for focus than the US or China, in efforts to limit ocean pollution; multinationals can have a huge impact on consumer behaviour and behavioural change. A focus on the mining sector may help to understand what is driving the desire for the mined minerals and how this may be tackled. Planetary health needs to identify root causes, not just diagnose and treat symptoms.

The discussions also raised questions about how the cause and symptoms should be identified: we are good at defining planetary ill-health, but less clear on what the practical vision of a healthy planet might be. If countries are to be asked to remain inside their planetary boundaries, planetary health must address what their transport systems, agricultural lands, energy grids and cities look like when they do.

How well do we understand the limits of the human body, and the extent to which our current lifestyles push these in negative as well as positive directions (as obesity and the rise in non-communicable diseases suggest they do)? What are the measures of good health beyond just the World Health Organization’s “absence of disease or infirmity”? What are the social determinants of this and do we sufficiently understand how a better environmental can drive good health as much we understand how the current one drives ill-health?

On the one hand, it is common sense to say air pollution is unhealthy, just as we know smoking is unhealthy, but without scientific evidence of levels of harm and a corresponding understanding of how healthy we might be without exposure to such risk factors, policy-makers will be loath to limit revenue and GDP-generating activities. Such quantified understanding will be particularly important if we are to “lock in” good practice to new technologies, urban developments and progress within the timeframes needed to keep our planet within manageable levels of environmental change.

We may overshoot planetary boundaries while we do so, but how far can we overshoot and still be able to (ever) recover? If there has to be trade-offs between population numbers, (average) length of life and current lifestyles – if the planet cannot support 12 billion people all living on average to 100 with an ecological footprint equivalent to the average North American – we must decide what we sacrifice and how: energy consumption, plastic use, a second child, the last 10 years of the current lifespan, or all four for some, none for others as inequality takes on new dimensions. Should we, and if so, how, incentivise people to make their own lives as healthy as possible, and tax into submission those who “choose” not to?

The key to all this is a better understanding of the casual chains that drive behaviours leading to degraded environments and their impacts on human health. The challenge is that these are not simple causal chains, but interconnected causal pathways that weave through complex systems. Each researcher might position their work along a single path, or at a single node of the network, but a planetary health researcher needs to see the entire system, and understand how every other causal chain affects theirs. This is no easy task, requiring academics to step outside of their own discipline into fields, methodologies and approaches with which they are less familiar as they inch towards an understanding of areas they have not considered before.

The solution may be as much about network analysis as it is about the epidemiology of malaria or the physics of diesel combustion, but more likely it is about all three (and dozens more). The answers to planetary health’s questions may lie at the end of research projects that are only now beginning, requiring today’s academics to work on current best estimates rather than certainties.

There is, nonetheless consensus around the idea that “if you’re not sick, you’re healthy” is as old-fashioned an idea for the planet as it is for the body. Better and more accurate early diagnosis of problems is needed so that they can be addressed swiftly and upstream, when doing so is easier. Prevention is better than cure, risk management is better approached through adaptation and mitigation than recovery. The researchers present saw this going beyond sustainability to something more wide-ranging, while also advising caution that the field may be looking too holistically before the specifics have been pinned down; incomplete understanding may shift problems elsewhere rather than solve them entirely. But planetary health research has to start somewhere. There may not be hard boundaries yet, but this should not be a barrier to practical suggestions on how to limit harm we can certainly see, if not yet fully quantify.

The debates are clearly far from over and offer plenty of scope for future discussions. If solutions are to be found, they will be composite approaches from different academic disciplines working together, creating an innovating and forward-looking interdisciplinary space from which equally innovative solutions can emerge. More researchers are welcome to join in as we take this forward.

By Jennifer Cole, Public Health Policy Advisor, Secretariat of the Rockefeller Economic Council on Planetary Health, University of Oxford; Connor Rochford, Blavatnik School of Government, University of Oxford; and Esther Schroeder, Worcester College, University of Oxford.

The opinions in this blog are those of authors alone, and do not represent the view of the entire Rockefeller Foundation Economic Council on Planetary Health.