The Korea Meteorological Administration forecasted on the 16th that the maximum daytime temperature next week will soar to 35 degrees Celsius. The tropical night, with minimum nighttime temperatures exceeding 25 degrees, has already appeared. It is hard to sleep when it is hot as the mind and body become exhausted. Experts advise maintaining a comfortable indoor environment and avoiding cold showers, beer, and coffee.
The reason for sleeplessness during tropical nights is hormones. When it gets dark in the evening, the brain produces melatonin, a hormone that induces sleep. Melatonin secretion is particularly vigorous around 2 to 4 a.m. However, when the weather is hot, our bodies become alert, which reduces melatonin secretion. Consequently, we cannot sleep as deeply.
Drinking milk can be a solution if you cannot sleep. The calcium in milk helps with melatonin secretion. Conversely, coffee, green tea, and alcohol disrupt deep sleep. Caffeine induces alertness. Although alcohol allows one to fall asleep quickly, it does not sustain sleep for long, causing one to toss and turn or wake up in the middle of the night.
Dr. Cho Cheol-hyun, a professor of psychiatry at Korea University Anam Hospital, noted, 'Humidity, temperature, light, and surrounding noise affect sleep,' adding that 'one should maintain a comfortable state that is neither too hot nor too cold.'
To achieve deep sleep in the summer, it is advisable to maintain an indoor temperature of 24 to 26 degrees Celsius and humidity at 50%. If the air conditioning is set too low, one might catch a cold from the air conditioning. Opening the window and using a fan to circulate air is also a good method. Wearing loose-fitting clothes that allow for proper ventilation or using bedding made of cool materials can help as well.
To create optimal body temperature for sleep, it is good to do light exercise, such as walking or stretching, for about 30 minutes in the early evening. Light exercise raises body temperature, which then gradually decreases, creating an ideal state for falling asleep. Showers after exercising should be taken with lukewarm water. Dr. Cho emphasized, 'Washing in water that is too cold right before sleeping can actually put our bodies in a tense state.'
It is better to avoid late-night snacks in the summer as they can raise body temperature. Consuming late-night snacks can make it difficult to fall asleep as the body generates heat to focus on digestion. In particular, foods that are very sweet or high in carbohydrates raise blood sugar levels and stimulate insulin secretion, which disrupts sleep.