Hot weather can mess with your mind.
According to a study published in 2022 in JAMA Psychiatry, mental health emergencies are exacerbated in hot weather; emergency rooms see a higher number of visits for anxiety, mood disorders, stress and substance use when it’s hotter out than normal. Additionally, research shows that violent crime increases in the summer.
“As a general rule, I think all of us clinicians especially agree that there is a really interesting demonstrable relationship between heat and a whole cluster of interpersonally antisocial behaviour,” said Kim Gorgens, a clinical professor in the Graduate School of Professional Psychology at the University of Denver. “So, irritability, hostility, aggression, being discourteous — not necessarily criminal behaviour, although there’s an association there, too, but a much bigger bucket.”
Why is this? And what can you do to prioritise your mental health during a summer chock-full of heat waves? Here’s what experts say:
It could come down to stress.
“Extreme heat, when it’s prolonged ... it’s an environmental stressor that people don’t have control over,” said Michael Groat, the director of psychology at Silver Hill Hospital, a mental health care facility in Connecticut.
And the feeling of loss of control over a situation isn’t good for your mental health. “Having a sense of control is [important] for recovery from depression, it’s also, just generally speaking, helpful when dealing with stress,” Groat noted.
On top of that, the heat can be chronic and inescapable, especially if you spend a lot of time in places with no (or weak) air conditioning. According to Groat, ongoing stressors can create a sense of fatigue and even make people irritable.
“And if you look at some of the symptoms of extreme stress over time, they closely overlap [with] the symptoms of depression ... difficulties with concentration, fatigue, feeling like one is losing motivation. It can also lower your mood,” he added.
So, that prolonged strain you’re feeling during a heat wave, particularly if you have an underlying mental health condition, can put you over the edge.
Anxiety surrounding climate change can’t be discounted.
We’d be remiss not to point out climate change and how that can impact stress levels, too.
“We see a lot of people who equate and link these more extreme weather [events] as indicative of permanent changes to the climate,” Groat said. “Those permanent changes to the climate elicit, for a lot of people, fear and anxiety about, ‘OK, what does this say about our future?’ ‘What does it say about other extreme weather that we might be facing?’”
If you think this sounds like very real existential dread, you’re not wrong. “We’re hearing a lot more of those kind of existential anxieties that are coming up,” Groat said.
People may find themselves asking questions about how this will impact their children or grandchildren, or what this means for our oceans and forests. And it’s hard not to let questions like that stress you out.
Heat-induced sleep disturbances don’t help your mood, either.
Getting a good night of sleep when it’s hot out is no easy feat. Waking up sweaty in the middle of the night, general discomfort or having trouble falling asleep are things most people can likely relate to.
This, Groat said, also contributes to some of the stress that occurs because of high temperatures.
“And one thing that we know from a lot of research looking at various kinds of mental health disorders — anxiety, depression, bipolar illness, schizophrenia — is that sleep disturbance like insomnia, waking up, these kinds of things have a direct impact on mood and sense of well-being,” Groat said.
At-risk populations suffer most during a heat wave.
Unfortunately, as with many situations, at-risk populations are most impacted by extreme heat.
“People who are mentally ill are among the highest risk for really poor health outcomes during peak crises ... they’re some of the first to die, they’re highest risk for heat stroke,” Gorgens said.
And this also applies to people with certain physical health comorbidities. For these populations, extreme heat is especially dangerous, she said.
The inequities in society come into play here. For example, someone who is having a mental health crisis in a space with no air conditioning is more likely to leave a stuffy room for fresh air. (On a mild day, this likely wouldn’t happen outdoors.) This could contribute to increased rates of mental health emergencies — these emergencies are simply more visible on a hot day compared to a temperate day.
What’s more, research shows that people in unjust situations are more likely to experience feelings of aggression and difficult thoughts, Gorgens said. “There’s a really important correlational relationship between increased heat and antisocial behaviour. And it is disproportionately impacting marginalised communities. And it’s not getting better anytime soon without some really deliberate advocacy and intervention,” Gorgens said.
During heat waves, consider reaching out to elderly folks, neighbours with limited mobility and people in your life with mental health struggles, Gorgens added. This could mean calling up a friend just to talk during a heat wave, offering your guest room to your niece who doesn’t have air conditioning or bringing over cold water bottles to your friend from church. There are many ways to support those who need it.
It’s worth noting that some research shows higher incidents of kindness, too.
Grogens said there is a sidebar of research that also shows that acts of kindness and altruism increase during heat waves. But while this data exists and is important to point out, Gorgens said there is more robust research and real-life data pointing the other way.
“I don’t think anybody who is working in emergency rooms, who’s doing humanitarian refugee [work], who is a co-responder in an ambulance would have any perspective other than heat creates a crisis,” Gorgens said.
It’s important to take care of yourself (in addition to others) during heat waves.
According to Groat, it’s important to be self-aware when you’re dealing with an ongoing stressor like a heat wave. He said you can do a quick body scan to determine how the heat may be impacting you: Are you feeling sweaty? Anxious? Stressed? Take time to understand how you’re feeling.
Additionally, think about what you can do to take back some control in this situation. “One of the foundational principles of recovery from depression, or really any mental illness, is the involvement of our own sense of agency,” Groat said.
So if the hot weather is keeping you from your regular outdoor run, try going for a swim instead or on a power walk through your local mall. This can help you feel less helpless — there are things you can do to combat this weather and still stick to a version of your routine.
He noted that exercise is a good stress reliever too, which is a benefit during a time when you may be feeling heightened levels of stress. Stress reduction could also look like getting together with friends, journaling or switching on your favourite show.
“The more we can do to relieve stress, the less likely we are to be showing the stress-related symptoms that are connected to heat,” Groat said.