In the event of acute danger, our survival instinct can take over through so-called escape or combat response.
It prepares the brain and muscles for action, but also kicks off the immune system.
This reaction can also be activated, for example, by watching a horror movie.
- An interesting study showed that those who finished their morning shower with cold water for 30 seconds reduced their sick leave by 30 percent, says Glen Davison, researcher in sports and immunology, in the World of Science - Boost your immune system.
When host Ronx Ikharias was confronted with his fear of spiders, the number of immune cells increased by 20 percent in just twenty minutes.
In the clip above, you can see the terrifying encounter with the bird spider Charlotte.
The whole world of science - Boost your immune system, you can watch Monday 14 June 20:00 on SVT2, or already now on SVT Play.