Introduction
As global temperatures continue to climb, a growing concern is emerging: how heat affects mental health. The impact of rising temperatures reaches far beyond physical discomfort or environmental harm-it directly influences our emotional well-being. From sleep disruption and anxiety to worsening psychiatric conditions, heat is becoming a serious psychological stressor.
This blog explores the hidden mental health consequences of a warming planet and how a One Health approach can help us understand and address these challenges.
What are the hidden psychological effects of rising temperatures—and how can a One Health approach help us respond?
How Heat Affects Mental Health
1. Heat and Mood Dysregulation
High temperatures have a measurable effect on emotional stability and behavior. As the mercury rises, so do rates of aggression, irritability, and impulsive behavior. A large-scale study found that violent crime and suicide rates increase during prolonged heatwaves, suggesting that temperature can disrupt neurochemical balance and impulse control [1].
In urban areas, where heat island effects amplify ambient temperatures, these mood disruptions are even more pronounced. Poor ventilation, limited access to green spaces, and overcrowding further compound psychological stress.
2. Sleep Disruption
Sleep is foundational to mental health, yet it is one of the first physiological processes affected by heat.
Elevated nighttime temperatures can lead to restless sleep, frequent waking, and shortened REM cycles, which in turn trigger daytime anxiety, reduced concentration, and depressive symptoms [2].
Vulnerable populations such as the elderly, shift workers, and those without air conditioning experience the worst effects—often facing a cycle of poor sleep and deteriorating mental health.
3. Exacerbation of Psychiatric Disorders
Heat not only affects the general population but also significantly worsens conditions for people with existing psychiatric diagnoses:
- Schizophrenia patients experience increased hospital admissions during heat events.
- Bipolar disorder and major depressive disorder are aggravated by heat-induced stress and dehydration.
- Psychotropic medications, including antipsychotics and antidepressants, can impair the body’s ability to regulate temperature, making patients more susceptible to heat-related complications [3].
In regions with inadequate mental health infrastructure, these risks are particularly concerning.
4. Climate Anxiety and Ecological Grief
Beyond the physiological impacts of heat, rising temperatures are symbolic of the broader climate crisis—a source of chronic stress for many. Terms like eco-anxiety, climate distress, and solastalgia (grief related to environmental loss) are entering the clinical lexicon. Young people, in particular, report worry, helplessness, and anger about a warming planet and uncertain future [4].
Who Is Most at Risk?
Certain groups are more vulnerable to heat-related mental health impacts:
- Older adults, whose thermoregulatory systems are less efficient.
- Children and adolescents who are neurologically more sensitive to environmental stress.
- Outdoor laborers and homeless individuals, due to prolonged exposure and limited shelter.
- Low-income households, often lacking air conditioning or healthcare access.
These populations not only face physical vulnerability but also psychosocial challenges that hinder adaptation and recovery [3].
A One Health Perspective
The One Health approach promotes an integrated view of human, animal, and environmental well-being. When applied to climate-linked mental health, it encourages:
- Recognizing environmental stressors like heat as mental health risk factors.
- Investing in urban greening, passive cooling, and equitable infrastructure to reduce exposure.
- Expanding climate-informed mental health services, particularly for vulnerable groups.
- Fostering interdisciplinary collaboration across climate science, psychology, and public health [5].
This systems-thinking approach is crucial for crafting scalable, sustainable solutions.
Adaptation and Mitigation Strategies
1. Green Urban Design
Urban planners can mitigate heat through tree planting, green roofs, and cool pavements. These efforts reduce temperatures, improve air quality, and provide psychological benefits through connection with nature [2].
2. Public Health Preparedness
Heatwave response strategies must incorporate mental health support, including:
- Deploying mobile mental health units to cooling centers.
- Training frontline workers in psychological first aid.
- Developing early warning systems that include mental health guidance.
3. Equitable Access to Mental Health Services
Expanding telehealth, subsidizing care, and removing structural barriers ensure climate-affected communities receive support. Collaboration with schools, community centers, and NGOs enhances outreach and trust-building.
Conclusion
The impact of increasing temperatures on mental health is a growing concern that intersects with environmental justice, public health, and urban resilience. Rising heat contributes to emotional dysregulation, psychiatric exacerbation, and climate-related psychological distress.
A One Health approach offers a holistic path forward—integrating environmental stewardship with psychological well-being. As climate threats escalate, protecting mental health must be a key pillar of adaptation.
References
- Burke, M. et al., 2018. Higher temperatures increase suicide rates in the United States and Mexico. Nature Climate Change, 8, pp.723–729.
- Obradovich, N. et al., 2017. Nighttime temperature and human sleep loss in a changing climate. Science Advances, 3(5), e1601555.
- Liu, J. et al., 2023. The role of psychotropics on heat-related outcomes in mental health patients. Psychological Medicine, doi:10.1017/S0033291723001825.
- Cunsolo, A. & Ellis, N.R., 2020. Ecological grief as a mental health response to climate change-related loss. The Lancet Planetary Health, 4(7), pp.e261–e263.
- WHO, 2022. Why mental health is a priority for action on climate change. Available at: https://www.who.int/news/item/03-06-2022-why-mental-health-is-a-priority-for-action-on-climate-change
