Indeed, heat can impact your brain and mood. Let's explore the reasons behind it.

 

"If you find yourself experiencing some brain fog lately, you might not be far off in attributing it to the heat.

In a study conducted a few summers ago in Boston, researchers examined young adults residing in college dorms during a heatwave. Some had the luxury of central air conditioning and slept in comfortably cool rooms at around 71 degrees Fahrenheit. However, others had to endure rooms without air-conditioning, where temperatures rose to approximately 80 degrees.

Over nearly two weeks, each morning, the students took various tests conducted on their cell phones. The individuals who slept in the hotter dorm rooms performed noticeably worse on the tests.

The assessments involved a math test requiring basic addition and subtraction, as well as the Stroop test, which involves mixing colors and words. Jose Guillermo Cedeño Laurent, an assistant professor at the Rutgers School of Public Health and the study's author, explains, "For example, if I display the word 'red' in the color blue, participants have to respond 'blue'."

Experiencing a slowdown in attention or reaction time is easy, and heat seems to be the culprit behind it. According to Jose Guillermo Cedeño Laurent, the study's author, the impact of heat on cognitive performance was striking, with response times and accuracy reduced by approximately 10%.

One possible explanation for this effect could be disrupted sleep due to heat, as it can be challenging to get a good night's rest in higher temperatures, leading to impaired focus and reaction time. However, there is also evidence suggesting that the heat itself may directly interfere with cognition.

In a similar study published in 2021, researchers observed a decline in cognitive performance when air temperatures reached 79 degrees. The study indicated that as the temperature increased, the activity in the parasympathetic nervous system, responsible for helping us remain calm and relaxed, decreased. Additionally, oxygen saturation levels in the blood were lower at higher temperatures, which the researchers believed could lead to reduced cognitive performance.

Other studies have also shown the impact of heat on office workers and standardized test scores, as mentioned by Caleb Dresser, an emergency medicine physician and the director of health care solutions at the Harvard Chan Center for Climate, Health, and Global Environment.

Research has shown that the impact of heat on our cognitive abilities and mood can be subtle but significant. For instance, one study indicated that workplace productivity peaks at around 72 degrees Fahrenheit and starts to decline in the mid-70s. Similarly, high school students performing standardized tests on hot days tend to achieve lower scores.

Caleb Dresser, an emergency medicine physician, highlights that various studies suggest heat can affect our cognitive functions, leading to reduced clarity, quick thinking, and efficiency. Additionally, heat may contribute to mood swings and irritability, partly due to elevated cortisol levels and stress responses.

While acclimating to heat is possible over several days of exposure, extreme and more frequent heatwaves have raised concerns about the ways heat can exacerbate mood and anxiety-related problems. A study published in JAMA Psychiatry in 2022 revealed a correlation between extremely hot days and an increase in hospital ER visits for mental health conditions.

According to Dresser, many physicians who have worked in hot conditions can attest to this concern. While mental health is a consideration at all times, it becomes an even more significant concern during exceptionally hot weather.

The impact of heat on mental health risks involves multiple factors, extending beyond changes in stress hormones and disturbances in sleep patterns. Caleb Dresser notes that vulnerable populations, including those experiencing mental health issues and individuals who are unhoused or have intermittent access to housing, are particularly susceptible.

Living outside during a heatwave can significantly amplify the risks. Dresser emphasizes that there may be complex social issues at play in these situations.

Gaining a comprehensive understanding of all these contributing factors could guide the development of strategies to prevent or manage the challenges posed by heat-related mental health risks. "As we adapt to a warming world with increasingly hotter summers, it is crucial to remain vigilant in recognizing dangerous conditions and taking necessary steps to ensure safety," Dresser advises.

One of the key strategies is to ensure proper hydration. While it may seem obvious, dehydration is quite common during the summer, and people often underestimate the amount of fluid they need to replace, especially when sweating excessively or spending time outdoors.

The college dorm study participants experienced the benefits of staying well-hydrated. Throughout the study, researchers sent text messages to all participants to inquire about their fluid intake. It was revealed that those who slept in the hot dorm rooms and consumed less than six glasses of liquid per day performed poorly on the tests. Previous research has also demonstrated that even mild dehydration can impair cognitive performance.

This serves as a reminder that a simple yet essential step like drinking plenty of water can safeguard not only our physical health but also our mental well-being.