Is it just me, or does this heat make you want to commit violent crimes?

I know that’s a strange way to start a blog, but I can explain! You see, research has proven that there’s a correlation between increased temperatures and incidence of violent crimes. Some people take the phrase “sun’s out, guns out” too literally. What’s fascinating is that this is only one of the ways which weather can influence your behaviour! If recent research is correct, climatic variables such as temperature, sunshine, and rainfall may exert an important influence on mental health. Today I would like to explore this potential impact with you, dear reader. Who knows, maybe it will distract you long enough to keep you out of jail…  

Firstly, it’s important to note that mental health is complex, and mental health conditions are likely influenced by many factors… which is exactly why we need research on this topic! The more we know about mental health and its risk factors, the better we can address it.

Seasonal Depression is the most well-known example of the link between climate and mental health, and is a condition wherein decreases in sunshine exposure during the winter months can cause a vitamin D deficiency, affecting serotonin and dopamine production in the brain, leading to depressive episodes. Seasonal depression is more prevalent in the Northern Hemisphere, where cold, grey winters may cause melatonin dysfunction, which can disrupt an individual’s sleep cycle. Sunlight exposure – which precipitates the production of vitamin D in the body – is thought to have a mostly positive effect on mental health, acting as a natural antidepressant. This has led to the development of light therapy, which has been used to treat depression, bipolar disorder, and schizophrenia by counteracting the vitamin deficiency that potentially underlies all these conditions.

However, it’s not all sunshine and rainbows (I found no research suggesting that rainbows impact mental health in any way, sadly). Some research suggests that the amount of sunlight that a pregnant person is exposed to may impact the likelihood that their child will develop a mental health condition later in life… which is fascinating! It’s believed that the impact of sunlight on both an individual’s circadian rhythm – in this case, the foetus’s circadian rhythm – and vitamin D levels may leave individuals more vulnerable to developing schizophrenia or bipolar disorder later in life! More research is needed on this topic, but it’s worth  keeping an eye on! 

Temperature, like sunlight, may also affect mental health through circadian dysfunction. Unlike sunlight, however, increased temperature is believed to have a predominantly negative effect on mental health. As was already mentioned, hotter temperatures lead to increases in violent crimes, as high temperatures cause discomfort and irritation, and encourage outdoor activities which lead to interaction with other people… which has also been known to cause discomfort and irritation for some. Beyond that, higher temperatures are believed to worsen symptoms of schizophrenia, bipolar disorder, and generalised anxiety disorder. Research suggests that increased temperatures negatively impact quality and quantity of sleep, and cause dysfunctions in the production of dopamine and serotonin – greatly worsening one’s moods. Conversely, there is some research which posits that high temperature exert a positive impact on depression, while lower temperatures worsen depressive symptoms!   

For my MSc I have been studying healthcare practitioners’ perceptions of the potential relationship between climate and mental health. Most of the existing research on this topic focuses on correlating hospital admissions to climatic conditions, and none of it has considered the experiences and perceptions of healthcare practitioners – experts whose knowledge and experience in the field, treating patients, may provide them with a unique, informed perspective on this potential relationship. Are healthcare practitioners even aware that this relationship may exist? Have they noticed a climatic influence on their patients’ conditions? If so, how do they react and attempt to manage this influence? All of these questions may give us better insight into the relationship between climate and mental health – a relationship, the importance of which, we are only beginning to understand…

Thanks for reading, I wish you lots of sunny days!

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