Horror movies are blood-curdling in more ways than one, a recent study featured in the Christmas edition of the British Medical Journal has revealed.
Dutch experts at Leiden University Medical Center conducted this research on a group of 24 students, alumni or members of staff from their facility. All of the participants were aged 30 or younger, and were considered to be in good health.
They were divided into 2 groups and had to watch 2 subsequent films, each lasting around an hour and a half: Insidious (a supernatural horror movie released in 2010) and A Year in Champagne ( a 2014 documentary about the popular sparkling wine).
Fourteen of them initially had to watch the horror flick, and then, about a week afterwards, at the same hour of the day, they had to continue with the pleasantly inoffensive educational movie.
The other 10 participants were given the same viewing recommendations, but were asked to start with the educational film instead, and finish with the terrifying one.
As the experiment unfolded, scientists measured each participant’s level of Factor VIII (anti-hemophilic factor), a protein whose production is dependent on the F8 gene and which plays an essential role in blood coagulation.
The blood tests were conducted approximately a quarter of an hour before and after each of the films was viewed, so as to identify possible modifications triggered by feelings of trepidation.
Participants also completed surveys assessing their level of fear from 0 to 10, with 10 being the equivalent of extreme panic and dread.
Overall, scientists discovered that subjects had rated Insidious as being significantly more spine-chilling than the documentary, its average rating being around 5.4 points higher.
It was also determined that when participants were viewing the horror flick, the levels of their Factor VIII protein climbed by as much as 11 IU/dl, which resulted in a higher risk of suffering venous thrombosis (blood clots inside the veins), as well as coronary heart disease and stroke.
The concentration of the anti-hemophilic factor was elevated among 57% of those who began by watching Insidious. In contrast, a surge in the levels of this protein was encountered among just 14% of those first viewed the documentary.
As the participants continued their cinematic experience, 86% of those who went on to watch A Year in Champagne displayed significant drops in the amount of Factor VIII. On the other hand, just around 43% of those who finished with the horror movie experienced a reduction in the blood coagulant factor.
Study author Dr Banne Nemeth believes that these findings are particularly significant, especially given the fact that every time the concentration of the anti-hemophilic factor rises by 10 IU/dL, this results in a 17% higher risk of developing potentially life-threatening blood clots.
Since watching terror-inducing films can result in a surge in this protein by as much as 11.1 IU/dL, this means that horror films aficionados literally experience blood-curdling sensations, which could eventually have detrimental consequences on their health.
Researchers do point out that the concentration of other proteins responsible for the formation of venous thrombosis remained unaltered during the study, but this may not have been the case for older participants or for those with underlying medical conditions.
As a result, they propose that this mechanism should be more thoroughly analyzed, so as to identify all the factors that contribute to the development of blood clots.
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