Can taking a cold shower cause a sudden stroke? No, that's not true: The Neurological Institute of Thailand told Lead Stories that taking showers with cold or warm water does not cause an immediate change in blood pressure, and does not lead to a risk of having a stroke.
The claim appeared in a video (archived here) on TikTok on November 30, 2023. The caption (translated from Thai to English by Lead Stories staff) read "Taking a shower the wrong way can cause sudden paralysis." It began (as translated):
Cold water causes high blood pressure and narrows blood vessels.
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Sat Feb 17 19:43:31 2024 UTC)
In the video, the person says (as translated) "Taking a shower with cold water in the winter will increase the body temperature and make the blood vessels shrink rapidly, causing high blood pressure and a stroke. This can make people fall in the toilet and become paralyzed."
Another video (archived here) on TikTok made a similar claim, mentioning that we should wet our feet before pouring water on the body or head, so that the body's temperature does not change too rapidly, causing an immediate change in blood pressure and a stroke.
A representative of the Neurological Institute of Thailand (NIT) explained to Lead Stories in a telephone conversation on February 2, 2024, that high blood pressure and a sudden rise in blood pressure are not the same. A stroke might happen to a high blood pressure patient, but it is not related to a sudden rise in blood pressure. To date, no research confirms that the water temperature of a shower can cause blood pressure to rise or that the sudden rise of blood pressure can cause a stroke, the representative said.
Starting with pouring water on specific parts of the body, such as the feet, does not matter as this does not change the body temperature or have any influence over blood pressure, they said. A cold shower does not cause the narrowing of blood vessels, inducing fainting or strokes, they said.
