News & Views
Policy Focus: Understanding the health impacts of climate change
Harriet Gay, Policy and Public Affairs Manager, The Physiological Society
“Policies based on the physiological understanding of how the human body responds to external stressors such as heat stress, air pollution exposure and hydration status for example can protect people earlier and more effectively, as well as show why climate action to reduce emissions is essential.”
Harriet Gay
Climate change presents a fundamental threat to human health, increasing the frequency and severity of risks such as rising temperatures, air pollution, and disruption to food systems. These impacts translate directly into physiological stress on the human body and are already contributing to ill health, loss of function and, in some settings, premature mortality, particularly among vulnerable groups.
Connecting physiological evidence to wider climate change resilience policy
There are persistent warnings of a worsening health crisis as a consequence of climate change, many of which were raised as part of the Society’s Global Climate and Health Summit last year. However, the policy response remains too fragmented, too reactive, and too disconnected from the evidence of how climate stress affects the human body. Evidence from physiology research shows that health harm as a result of climate change occurs earlier, more unevenly and for more people than many current policy frameworks assume, and often before failures in the wider system are visible.
Policies based on the physiological understanding of how the human body responds to external stressors such as heat stress, air pollution exposure and hydration status for example can protect people earlier and more effectively, as well as show why climate action to reduce emissions is essential.
As we saw in the discussions raised at the Society’s joint event with the Council for Science and Technology (CST) and the Foundation for Science and Technology (FST), resilience to climate change risks in policymaking is often considered in relation to the processes within specific sectors and systems that humans rely upon – such as infrastructure (energy systems and transport networks), primary industries (agriculture and food systems) or emergency services preparedness and disaster management.
The need for resilience and adaptability of these systems is driven by the purpose to support future stability, productivity, wellbeing, health, and safety. Therefore, alongside sector-specific resilient strategies, there needs to be a focus on the people themselves that these strategies are looking to protect.
In this sense, physiological resilience, being the capacity of people to maintain health, function and make decisions under environmental stress and recover afterwards, is a core component of climat resilience. It determines whether people can live, work and function as environmental conditions change.
Physiological thresholds and limits provide a way to understand where and how climate impacts become dangerous for people. Together, they define the boundaries of human tolerance. Physiological boundaries also make clear that there are conditions under which no amount of behavioural change or local adaptation can prevent harm. Without explicitly accounting for these physiological thresholds and boundaries, approaches and strategies risk being too vague, insufficient, or poorly targeted, particularly for those most at risk, for example due to pre-existing disease and/or comorbidities. For more information about this, please read our ‘Physiological thresholds and limits: foundations of climate resilience’ policy brief.
Strengthening evidence in cross-disciplinary collaboration
For the right evidence to be effectively integrated and considered in wider climate change resilience policies, there needs to be ongoing and growing engagement between experts and key stakeholders within government and across sectors. By demonstrating how physiology can support a human-centred approach to resilience, the Physiological Society continues to advocate for more physiological expertise to be included in key decision-making. For example, this year, the Society’s President Mike Tipton joined the UK Government’s Scientific Advisory Group in Emergencies (SAGE) expert list, which provides science advice to the Cabinet Office Briefing Room (COBR) during a crisis.
Next steps for the Society
The 2025 Global Climate and Health Summit, led by the Society, spotlighted a variety of regions, sectors, settings and population groups, including those with increased clinical vulnerabilities, where physiological thresholds and limits are being tested and human health is at risk.
A recurring theme throughout the two-day Summit was the impact of climate change on workers and workplaces. Speakers and delegates highlighted that standards and metrics intended to protect safety are often inconsistent, insufficiently embedded in policy, poorly enforced, or based on a ‘one-size-fits-all’ approach. This emphasised the need for stronger systemic risk management within workplaces as well as clearer standards, such as maximum working temperatures, that are informed by physiological evidence. Noting that physiological evidence is an important part of the wider picture, as it accounts for the limits and responses of the human body.
The Government’s Plan to Make Work Pay included a commitment to ‘modernising health and safety guidance with reference to extreme temperatures, preventative action and steps to ensure safety at work’. Combined with the key outcomes of discussions at the Summit, the Society is focused on delivery a policy project in 2026 directly looking at the intersection between climate change risks in the workplace and physiology. Targeting a specific focus area, such as workplaces, allows for direct and strategic messaging for policy action as well as a breadth of examples across population groups, including those with increased clinical vulnerabilities, industries and regions impacted by current challenges.
The project and report, aimed at policymakers and regulators, will highlight:
- The key physiological vulnerabilities and variables within the workplace that are caused or exacerbated by climate change
- How physiology research can better inform critical decision-making processes for health and safety related to climate risks, through considering physiological thresholds and limits.
- Where current regulations do not adequately reflect physiological insight
- Identify vulnerable groups currently being overlooked
- Research gaps
This project will engage expertise across the Society’s membership, alongside stakeholders from key organisations, and parliamentary and government decision-makers, with the aim of strengthening both the frequency and depth with which physiological considerations are integrated into climate risk planning, standards, strategies and policies. It will highlight the complex and non-uniform ways in which climate change affects human physiology, recognising that these impacts vary across populations, contexts, and exposures and therefore cannot be addressed through one-size-fits-all approaches.
Further integration of physiological research into key decision-making, both within government and across other organisations and sectors, would raise the profile of heat as a threat to the UK’s wider resilience as well as lays the foundation for follow-up work which protects the health, wellbeing and productivity of the workforce both now and in the future.
If you would like to be involved with this work and future work, please join the Climate and Physiological Resilience Network or contact our policy team: policy@physoc.org
