The link between heat and mental health is stronger than most people assume. In 2018, a landmark study led by Stanford University researcher Marshall Burke and published in Nature Climate Change found that when monthly average temperatures rise by 1°C, suicide rates increase by 0.7% in US counties and 2.1% in Mexican municipalities. A 2023 systematic review in The Lancet Planetary Health confirmed the broader pattern: rising temperatures and heatwaves are associated with poorer mental health outcomes. With Gulf summers holding above 40°C for months, this research deserves attention.
How heat reaches the brain
Researchers describe several overlapping pathways through which hot weather can affect the mind. The first is sleep. Warm nights make it harder to fall asleep and stay asleep, and disrupted sleep is one of the best-established triggers for irritability, low mood and emotional fragility. The second is physiological: heat stress changes how the body regulates itself, including blood flow and levels of serotonin, a neurotransmitter closely involved in mood. The third is behavioural — extreme heat drives people indoors, limits physical activity and face-to-face social contact, and raises overall stress levels.
The Imperial College London team behind the 2023 review adds an important note: some psychiatric medications can interfere with the body’s ability to regulate temperature. That means people already living with a mental health condition may be disproportionately affected during heatwaves — not because of the diagnosis itself, but because of how their treatment interacts with heat.
What the research found: heat and mental health in numbers
The Burke study, published in Nature Climate Change in July 2018, used multiple decades of mortality and climate records from the United States and Mexico. The headline finding: each 1°C increase in monthly average temperature was associated with a 0.7% rise in suicide rates in US counties and a 2.1% rise in Mexican municipalities. The effect appeared in both hot and cool regions and had not weakened over time, which the authors took as evidence of limited historical adaptation — people do not simply get used to heat. Analysing more than 600 million social media updates, the team also found that depressive language becomes more common during warmer periods, suggesting that mood deteriorates alongside the rising mercury. Looking ahead, the authors projected that unmitigated climate change could add 9–40 thousand additional suicides across the two countries by 2050 — a change they describe as comparable to the estimated impact of economic recessions, suicide prevention programmes or gun restriction laws.
Five years later, a systematic review and meta-analysis by Thompson, Lawrance and colleagues at Imperial College London, published in The Lancet Planetary Health in July 2023, consolidated the global evidence. It found that higher ambient temperatures, greater temperature variability and heatwaves were associated with increased suicide, more hospital attendance and admission for mental health disorders, and poorer mental wellbeing in the community. A Lancet commentary on the review put the pooled figures at a 1.7% increase in suicide incidence for each 1°C rise in mean daily temperature and 1.5% for each 1°C rise in mean monthly temperature.
What this means in the Gulf
For readers in Saudi Arabia and the wider Gulf, the relevance is hard to miss. Summer stretches for months, daytime temperatures routinely exceed 40°C, and even nights often stay warm — precisely the conditions that disturb sleep, one of the main pathways linking heat to mood. Much of life moves indoors under air conditioning, which helps, but outdoor workers, athletes training in the heat, older adults and anyone without reliable cooling remain exposed. There is also a pattern worth noticing: the Burke team found that heat effects were not limited to already-hot regions, which suggests that even very hot climates do not confer protection through familiarity.
None of these landmark studies were conducted in the Gulf itself, so local effect sizes remain unknown. What the evidence does support is treating prolonged heat as a factor that can weigh on mood and sleep — alongside work stress, lifestyle and everything else — and planning around it rather than dismissing it. For more seasonal health coverage, see more reads.
What the science does not say yet
Honesty about limitations matters here. First, these studies are observational: they reveal associations between temperature and mental health outcomes, not definitive proof that heat alone causes each outcome. Second, the Lancet review itself flagged that the quality of available studies varied widely, and rated the certainty of the exact effect sizes as low — studies measured temperature and outcomes differently, and whole regions (the review highlighted South America) remain largely unstudied. Third, the 2050 projections depend on a high-emissions scenario (RCP8.5); real-world outcomes will depend on how fast emissions fall and how well cities adapt. Finally, heat is one factor among many: socioeconomic conditions, relationships and access to care matter enormously. A hot week is not a sentence to low mood — it is a reason to be a little kinder to yourself and more attentive to the people around you.
Practical takeaways
- Keep your bedroom cool and protect your sleep schedule: warm nights are one of the clearest pathways between heat and mood.
- Move outdoor exercise, errands and social plans to early morning or after sunset, and avoid peak heat around midday.
- Hydrate consistently through the day — dehydration adds fatigue and irritability on top of the heat itself.
- During heatwaves, check on family and friends living with a mental health condition, especially those taking psychiatric medication, as some medicines affect temperature regulation.
- If low mood, poor sleep or irritability persists through a long hot spell, treat it as a signal worth discussing with a doctor or licensed mental health professional.
Sources
- Burke et al., Higher temperatures increase suicide rates in the United States and Mexico — Nature Climate Change (2018)
- Thompson, Lawrance et al., Ambient temperature and mental health: a systematic review and meta-analysis — The Lancet Planetary Health (2023)
- Imperial College London — Rising temperatures may be associated with poorer mental health, review suggests
- Stanford FSI — Higher temperatures increase suicide rates in the United States and Mexico
The information in this article is for educational purposes only and does not substitute professional medical advice. If you are struggling with your mental health, consult a physician or licensed mental health professional.
