A Dutch study of 3,000 people who added 30 to 90 seconds of cold water to their showers found one result: they missed fewer days of work. But they got sick just as often. Cold showers didn't prevent illness, just made people more willing to work while sick.
Chapters
One large, truly large study of cold water exposure that I, that I was able to find, I think there were about 3,000 people. It was done in the Netherlands, and they had, they had them do normal shower every day and then finish with 30, 60, or 90 seconds of just ice cold. And then they looked for, after a month, they looked for differences. The only difference they found was that the, the people doing the cold showers missed fewer days of work, so they went to work more. Now the interesting thing about that is they were actually sick the same number of days. They just went to work. They were, they were motivated. Yeah, like, yeah, I'm sick, but I just did this terrible cold shower, so I can do anything today.