A new study looking at stress in medical students found that, counter-intuitively, the “stress hormone” known as cortisol appears higher during the laid-back summer months than other times of the year. Researchers at Poznan University of Medical Sciences in Poland looked at levels of cortisol – a hormone that is released into the bloodstream in response to stress – at different times of the year. The study subjects – medical students – tended to have higher cortisol levels in the summer. Dominika Kanikowska, lead author of the study, says they do see seasonality differences in animals, but more and more results show that seasonality is also connected with human beings.
It must be fear of being seen in a bathing suit.