As the UK braces for another weekend of high temperatures, with forecasts of up to 29°C in parts of England and Wales, health experts are warning that heatwaves can significantly impact mental wellbeing. Dr Ravi Gill, a health psychologist, explains that prolonged heat disrupts neurotransmitter systems, impairs sleep, and raises stress hormones like cortisol, leading to increased anger and anxiety.
Physiological changes during a heatwave can strain emotional resilience, making minor irritants feel overwhelming. Dr Gill notes that heatwaves can escalate social tensions, turning minor triggers into conflicts. People with pre-existing mental health conditions are particularly vulnerable, as some medications reduce the body's ability to regulate temperature.
High nighttime temperatures further compound the problem by disrupting sleep, particularly REM sleep, which is vital for emotional processing. Poor sleep lowers activity in the prefrontal cortex, responsible for impulse control, and heightens amygdala reactivity, linked to fear and anger. This makes individuals more emotionally volatile and less resilient to everyday frustrations.
Heatwaves also impair cognitive functions such as memory, focus, and decision-making. Reduced cerebral blood flow, neurotransmitter disruption, and electrolyte imbalance all contribute to mental sluggishness. Even mild dehydration can slow neural processing and impair memory and attention.
To counter these effects, Dr Gill advises drinking water regularly, not just when thirsty, and including electrolyte sources. Staying cool, maintaining a consistent sleep schedule, and practising relaxation techniques can also help manage mood and reduce anxiety during hot weather.
