The temperature in the bedroom has a direct impact on the functioning of the cardiovascular system. According to a study published in the journal BMC Medicine, heat at night puts an additional strain on the heart, especially in people over 65. The results are also reported by the Daily Mail.
Researchers at Griffith University have found that bedroom temperatures above 24°C can already prevent the body from fully regenerating during sleep. Normally, at night, the heart rate slows, blood pressure drops, and the body goes into rest mode. However, in hot conditions, the body is forced to work harder to cool itself, which increases the strain on the heart.
Temperatures above 28°C are considered particularly dangerous. According to the study, in such conditions the risk of critical stress on the cardiovascular system increases almost threefold. At a temperature of 24–26°C the risk of cardiac stress increases 1.4 times, and at 26–28°C it doubles.
Experts explain that heat causes blood vessels to dilate and the heart to beat faster, even at rest. This reduces heart rate variability, an important indicator of how well the body recovers during sleep. Prolonged exposure to high temperatures can contribute to high blood pressure, hardening of the arteries, and the formation of blood clots, which increases the risk of heart attack and stroke.
Dr Fergus O'Connor says hot nights are a heart-wrenching problem, regardless of daytime temperatures, and that the problem is becoming global. He says the number of warm nights is increasing as climate change continues, which could affect future heat stress mortality rates.
At the same time, there are currently no clear international recommendations on the optimal nighttime temperature for sleep. Doctors advise maintaining a comfortable microclimate in the bedroom, avoiding overheating, and ensuring sufficient ventilation, especially for people with cardiovascular diseases.
