The triple planetary crisis, a convergence of anthropogenic climate change, biodiversity loss, and pollution, is driving global health inequities by adversely and unequally affecting human and ecosystem health. The scale of the crisis is growing fast while measures to protect the planet and populations are yet scarce. Seven of the eight safe and just planetary boundaries have already been breached, with 86% of the global population being affected by at least two breaches. However, the health impacts of the planetary health crisis are unequally distributed among world regions, populations, and individuals, an issue scientists suggest must be addressed by targeting individual behaviours as well as structural drivers of inequality.
High-income countries are disproportionately responsible for driving planetary health crises, while low-income countries bear the greatest vulnerabilities and health impacts. Even within high-income countries, health impacts are unequally distributed, with the greatest effect on low-income households and older populations.
The comment published in Nature Human Behaviour suggests that understanding sources, pathways, and patterns of systemic inequality under the conditions of the triple planetary crisis is crucial for transformative change in addition to fundamental shifts in socio-economic and environmental governance systems. Further research and policy development in the field should support these transformations. At present, many policies are developed in isolation without considering the interconnectedness of planetary challenges and health. There are also data gaps and limited research on how the triple planetary crisis affects populations and regions differently.
Health inequities from a systems perspective
Health equity means every individual has a fair and just opportunity to reach their highest potential level of health regardless of social, economic, or demographic factors. In the triple planetary crisis, health inequalities are mainly affected by three factors.
Exposure: how much people encounter hazards and cascading ecosystem effects based on geography, occupation, or living conditions.
Vulnerability: how much hazards affect them, depending on factors such as age, financial conditions, illness, housing and living conditions, access to health care, etc
Coping capacity: system-level protective factors to prevent or manage harm, including resources, adaptation measures, information, preparedness, and community and individual capacity to use resources.
Planetary health crises can worsen and reinforce the already existing inequalities, leading to what academics call an inequality reinforcement trajectory. These trajectories lead vulnerable populations to an eco-syndemic situation- where environmental changes, health issues, and social conditions worsen the population’s health.
Individual behaviours and systemic conditions
Individual behavioural changes are central to adapting to the triple planetary crisis and health outcomes. However, individual behaviours are always influenced by physical, social, and economic conditions. High- income countries and individuals are better positioned to change behaviours as there are more opportunities that help and fewer contextual barriers to transition. Also considering the inequity between those who are highly responsible for planetary crises and those who are most affected by it, scientists suggest high-income settings need an ambitious behaviour change to support climate action. This includes more plant-based diets, sustainable transport choices, reducing plastic use, and shifting towards environmentally friendly infrastructure.
The way forward
Climate and environmental changes are unequally affecting the populations around the world. In this scenario, how can health equity be achieved amidst the triple planetary crisis?
Scientists have clear recommendations for researchers and policymakers to advance current knowledge and facilitate health equity action.
Important areas for research
| Actions | Methods/ Examples |
| Closing geographical and monitoring data gaps | Closing data gaps in exposure and vulnerability assessment by combining satellite data, routine health data and community mapping data in regions where official data are sparse |
| Assessing compound and cascading risks in an eco-syndemic perspective | For example how co-occurring hazards such as flood, heat and pollution interact with pre-existing disease burdens and how they cluster spatially in deprived areas. |
| Improving effectiveness of climate action to protect vulnerable populations from long term risks of climate and environmental changes | For example differentiating between health risk groups and environmentally unequal populations while studying greening in urban design on heat related mortality and morbidity |
| Ways to shift to sustainable consumption | For example, studying whether household counselling helps people to transition to sustainable plant-based foods. Examining the effects on nutrition, health, and the environment, as well as the different reasons and challenges that influence dietary changes among low- and high-income groups. |
| Equity effects of climate and environmental policies | Evaluating interventions such as low-emission zones, greening programmes and heat action plans to assess whether they inadvertently increase health inequities |
| The role of awareness, empowerment, and planetary literacy among individuals and communities in catalysing change and vice versa, ways in which ecosystem interventions empower communities | For example studying the role of community-based participation in supporting and protecting nature based solutions |
| Economic value, health co-benefits and trade-offs of mitigation and adaptation policies | Studies measuring the health and productivity benefits of heat-resilience or health and economic value of forests and wetlands conservation or restoration. |
Important areas for policy
| Actions | Methods/ Examples |
| Redesigning urban and living environments through a health equity lens. | Urban planning that enables inclusive mobility, actions like community gardening that will consider the needs of deprived urban residents. |
| Promoting equitable access to essential resources | Ensure fair access to housing, energy, healthcare, recreation and sustainable transport. Policy makers can consider a right based approach rather than a market-based mechanism. |
| Directing climate and health finance towards most affected populations | Prioritise vulnerable populations and regions in climate adaptation and loss-and-damage finance. Better action in regions that are least responsible for, but most affected by, climate change |
| Empowering communities as producers of knowledge, not just recipients | Involve communities in mapping risks and collecting geodata, which can guide health outreach investments, and in designing programmes that are meant for behavioural shifts. |
| Building equitable environment and health surveillance infrastructure | Integrating environmental data, health records and community monitoring to make inequities visible. Investing in data capacity of low- and middle-income countries. |
| Embedding distributional health impact assessment in climate policy instruments. | For example climate and environmental policies could go through a spatial audit before being implemented to analyse which neighbourhoods may gain or lose. |
Influencing individual behaviours, structural reforms and public policy are all needed for a transformative change. An integrated approach embracing both individuals and contexts in which they operate is the way forward for addressing health inequities driven by the triple planetary crisis.
Reference: Toprakkiran, N., Treskova, M., Tosun, J. et al. Rising health inequities require looking beyond health systems. Nat Hum Behav 10, 1618–1621 (2026). https://doi.org/10.1038/s41562-026-02565-7
