March 3, 2024

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NHK: Don’t catch cold after taking a hot bath in winter

NHK: Don’t catch cold after taking a hot bath in winter

NHK: Don’t catch cold after taking a hot bath in winter,  beware of “heat shock”.  NHK news: Mr. Norizumu shared that his family also had a “heat shock” incident. A few years ago in February, she heard a strange noise from her husband in the bathroom while watching TV, but there was no response to calling or knocking on the door. The bathroom door was blocked and could not be opened. She forcibly opened the door and found her husband lying on the ground, slowly regaining consciousness.

 NHK: Don't catch cold after taking a hot bath in winter


Norizumu’s husband is 40 years old and does not have high blood pressure. He likes bathing. The husband drank half a bottle of red wine before this bath, which may be the main cause of heat shock. Everyone may have “heat shock” after taking a bath, especially families with elderly people should be especially careful.

Maeda Shinji, a professor at the International Medical Welfare University in Japan, said that rapid temperature changes can cause a sudden increase or decrease in blood pressure, causing syncope or heart attack, which is called “heat shock.” During the winter bathing process, we enter the cold bathroom from the warm room and then into the warm hot water. During this process, blood pressure will fluctuate up and down, and there is a risk of heat shock.

NHK: Don't catch cold after taking a hot bath in winter

In 2019, about 4,900 elderly people in Japan died of “heat shock” after bathing, which is 1.5 times more than 10 years ago. As shown in the figure, the death peak is from November to April of each year, and the risk is highest in January.


In order to prevent “heat shock” in bathing, we need to take the following safety measures:

  • 1. Increase the temperature of the changing room and bathroom before taking a bath;
  • 2. When taking a bath, the water temperature should be controlled below 41 degrees, preferably not more than 10 minutes;
  • 3. Don’t suddenly stand up from the water after taking a bath;
  • 4. Do not take a bath immediately after eating, drinking or taking certain drugs;
  • 5. Talk to your family before taking a bath.

Affected by the epidemic, it is necessary to be more vigilant about “heat shock” this winter. In order to control the epidemic, we need to open windows frequently for ventilation, which may cause heat shock due to sudden cold.

In an interview with NHK, a nursing staff at a welfare facility in Hokkaido said that in order to prevent influenza, the facility must open windows for ventilation every winter. As long as you follow the correct steps, even in very cold Hokkaido, you can breathe safely.

  • 1. Don’t open one window completely. You can open multiple windows a bit to avoid cold wind entering the room at once.
  • 2. In order to keep the indoor temperature constant, you can turn on the air conditioner and send in warm air during the ventilation process.
  • 3. Use a humidifier to maintain indoor humidity to prevent drying while slowing down the rate of room temperature drop.
  • 4. We can ventilate when the elderly go to other rooms to eat, and the room temperature can slowly recover after returning to the house.

Infectious disease expert, Professor Yoshiaki Katsuta of Kansai Welfare University also stated that the purpose of ventilation is to let the air flow and dilute the air aerosol, not to lower the room temperature. If we get the purpose of ventilation wrong, open all the windows in order to lower the room temperature, the rapid temperature changes may cause heat shock. Therefore, we can put outside air into an empty room or corridor, close the windows, open the doors of other rooms, and use the “two-stage ventilation” method to effectively ventilate while slowing down temperature changes and avoid sudden heat shock.

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