Less sunshine may worsen anxiety and depression symptoms, new research suggests

Reduced sunshine and warmer weather may lead to more people seeking urgent mental health care, according to a new study published in Frontiers in Psychiatry.

Researchers found that even normal day-to-day weather changes can affect when people seek help for mental health conditions such as anxiety, depression, sleep problems, and alcohol-related disorders.

The findings are based on an analysis of mental health-related healthcare visits across England between 2014 and 2022. The researchers say understanding how weather affects demand for mental health services could help hospitals and healthcare providers prepare for busier periods.

Mental health disorders are among the leading causes of illness worldwide. Conditions such as depression, anxiety, and psychosis affect millions of people every year and place a heavy burden on individuals, families, and healthcare systems.

Although previous research has shown that extreme weather events, such as heatwaves, can affect mental health, less is known about how everyday weather influences people’s need for care.

To better understand this, researchers examined more than 4.6 million mental health-related contacts made through three healthcare services in England: NHS 111, hospital emergency departments, and out-of-hours general practice services. They compared these records with daily weather data, including temperature, sunshine, and rainfall.

The study found that sunshine had the clearest link with mental health service use. On days with fewer hours of sunshine, more people sought urgent mental health care. The increase was seen across all three healthcare services, suggesting that lower sunlight may make it harder for some people to cope with existing mental health conditions.

Reduced sunshine was also linked to more healthcare visits for anxiety and depression. Researchers say sunlight helps regulate the body’s internal clock and mood, so a lack of sunshine may worsen symptoms in some people.

Temperature also had an effect, although it was less consistent. As temperatures became warmer, calls to NHS 111 and visits to emergency departments increased until the temperature reached about 18 degrees Celsius. After that, the number of visits remained steady or began to fall. Overall, mental health-related healthcare visits changed by about 17 to 20 per cent between cooler and warmer days.

The study found that older adults were more likely to visit emergency departments during both cold and warm weather, showing they may be more sensitive to changes in temperature than younger people.

Warmer weather was also linked to more healthcare visits for alcohol-related problems, drug overdoses, and sleep disorders. However, researchers found little evidence that temperature had a major effect on healthcare visits for self-harm or depression. Colder weather was linked to fewer visits for anxiety in some healthcare settings.

Unlike sunshine and temperature, rainfall did not appear to have a clear effect on mental health service use. Whether there was heavy rain or dry weather made little difference to the number of people seeking urgent mental health care.

The researchers also found that the results were similar across different parts of England and remained the same even after removing data collected during the COVID-19 pandemic. This suggests the findings were not influenced by the pandemic.

The researchers emphasised that the study does not mean that weather causes mental illness. Instead, it suggests that weather changes may affect when people decide to seek help. For example, reduced sunshine or warmer temperatures may make symptoms feel worse or more difficult to manage, leading more people to contact healthcare services.

The findings could help healthcare providers plan. By using weather forecasts alongside health data, hospitals and mental health services may be able to predict when demand is likely to increase and ensure staff and resources are available to support patients.