Heat and Mental Health: New Study Explores Vulnerability and Heat Protection
Study Shows Declining Well-Being on Hot Days – Current Follow-Up Study Explores New Approaches to Effective Heat Protection.
A research project at the University Clinic for Psychosomatic Medicine and Psychotherapy in Magdeburg (Director: Prof. Dr. Florian Junne), in collaboration with the University Clinic for General Internal Medicine, Psychosomatics, and Psychotherapy in Heidelberg, is conducting the first systematic investigation into how high temperatures affect mental and physical well-being and what factors motivate people to adopt effective heat-protection behaviors.
When temperatures rise, it’s not just the body that suffers—the mind also comes under strain. Researchers at the University Clinic for Psychosomatic Medicine and Psychotherapy in Magdeburg have investigated how heat affects mental and physical well-being in everyday life and what factors motivate people to protect themselves from heat-related health risks. The results show: Temperatures as low as 25 degrees already lead to reduced mental and physical well-being. People who are simultaneously dealing with both mental and physical health issues are particularly at risk.
Feelings of anxiety and depression increase in the heat
In the first of two sub-studies, Ecological Momentary Assessment (EMA) was used to investigate how heat directly affects mental and physical stress. EMA is a method for real-time, real-life surveys conducted via smartphone. In the summer of 2025, 183 participants from the general population as well as from the psychosomatic outpatient clinics at the University Hospitals of Magdeburg and Heidelberg were surveyed four times a day on days when temperatures exceeded 25 °C. The results show: On hot days, the likelihood of reporting anxiety or depressive symptoms increases. This effect is particularly pronounced among individuals who have pre-existing mental and physical health conditions. Thus, the project provides the first real-life data for Germany demonstrating the link between high outdoor temperatures and mental health in a naturalistic setting.
Photo: Assistant Professor Dr. Hannah Wallis is researching how physical and psychological stressors and environmental factors interact—ranging from societal changes to extreme weather events. Photographer: Sarah Kossmann/Magdeburg University Medical Center
Risk Perception and Self-Efficacy Are Crucial for Protective Behavior
Another part of the study also addressed the question of why some people take specific preventive measures during heat waves while others do not. In a representative cross-sectional survey of 1,803 adults in Germany, psychological determinants of heat-protective behavior were analyzed. The findings show that risk perception and self-efficacy are closely linked to actual protective behavior. Emotion plays a particular role here—specifically, whether participants associated heat with negative feelings.
Current follow-up study examines the influence of targeted risk communication
Building on these findings, the research team has been conducting a follow-up study since the summer of 2026 to investigate whether the perception of heat-related risks changes over the course of the day and whether targeted information can motivate people to take protective measures in a timely manner.
To this end, 539 participants are currently being surveyed several times a day via a smartphone app on 14 days during the summer (when temperatures reach 25 °C or higher) regarding their heat-related risk perception, their perceived ability to protect themselves, and their actual protective behaviors. In addition, they receive heat protection information as part of an experimental design. This allows researchers to examine for the first time whether and how the type of communication influences protective behavior in the short term.
Given that more than 60,000 people in Europe already die each year from heat-related causes, these questions are highly relevant. Estimates for Germany predict an increase to between 12,000 and 42,000 annual heat-related deaths by the end of the century. Behavior-based prevention, which focuses on the right moment and the right approach, could make a significant contribution to reducing these numbers.
“Our data show that heat can directly impair mental well-being, especially among people with pre-existing conditions. At the same time, we know that psychological factors such as risk perception and self-efficacy drive protective behaviors,” explains study leader Jun.-Prof. Dr. Hannah Wallis of the University Clinic for Psychosomatic Medicine and Psychotherapy in Magdeburg. “With our ongoing study, we’re taking the next step: We want to understand when and how risk perception arises in everyday life and leads to protective behaviors, in order to enable the development of effective preventive measures for heat waves.”
The SWEATR research project—Mental Health in Hot Weather: Stress, Risk Perception, and Protective Behaviors—is part of a collaborative project with the Institute for Social Medicine and Health Systems Research on “Implementation Research Saxony-Anhalt (ISA)” and is funded by the European Regional Development Fund (ERDF).
Scientific Contact:
Jun.-Prof. Dr. Hannah Wallis, W1 Junior Professor of Physical Stress Disorders at the University Clinic for Psychosomatic Medicine and Psychotherapy in Magdeburg, hannah.wallis@med.ovgu.de