Aarhus University, Denmark, researchers suggest that recreational fear experiences, such as haunted house attractions, may reduce inflammation in individuals with low-grade inflammation.

Fear and acute stress reactions are fundamental survival mechanisms that activate the adrenergic system, prompting vital fight-or-flight responses. While chronic stress is associated with unhealthy low-grade inflammation, brief activation of this system has been seen to positively impact the immune system. The Aarhus team was curious about the potential effect of voluntary fear exposure on human inflammation levels.

In their study, “Unraveling the effect of recreational fear on inflammation: A prospective cohort field study,” published in the journal Brain, Behavior, and Immunityresearchers recruited 113 adult visitors to a high-intensity haunted house attraction in Vejle, Denmark.

Participants, with a mean age of 29.7 years, included 69 females and 44 males. Heart rates were monitored throughout the event, which lasted an average of nearly 51 minutes, and self-reported fear levels were recorded using a Likert scale ranging from 1 to 9.

Blood samples were collected just before, immediately after, and three days after the event to measure high-sensitive C-reactive protein (hs-CRP) levels and immune cell counts. Low-grade inflammation was defined as hs-CRP levels greater than 3 mg/L.

Twenty-two participants exhibited low-grade inflammation before the event. Of these, 18 participants (82%) showed a decrease in hs-CRP levels three days after the event, dropping mean levels from 5.7 mg/L to 3.7 mg/L. Total leukocytes and lymphocytes decreased across the entire cohort when comparing levels before and three days after the event, although mean levels remained within the normal range.

Decreases in inflammatory signal markers among those with initial low-grade inflammation suggest that the recreational fright experience may diminish immune responses. No significant proportional difference was found in the number of participants with low-grade inflammation when comparing levels at the event (19.5%) and three days after the event (16.8%).

These findings align with animal studies showing that acute stress can mobilize inflammatory cells and prepare the immune system for potential trauma or infection.

People often engage in activities that elicit fear for recreational purposes, from ghost stories and jump scare pranks to modern horror films and haunted attractions. This haunted house experiment suggests that such experiences may not only provide thrills but also potential health benefits by modulating immune responses.

Further research is needed to confirm the observed effects and explore the mechanisms underlying the relationship between recreational fear and immune function before clinical applications can be considered significant enough to incorporate acute fear into a health care setting.

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