According to Time Magazine, a study was performed on 114 men ages 18 to 44, that revealed the higher the testosterone levels, the more capsaicin, or pepper, they preferred on their food. The University of Grenoble-Alps in France performed the study, which required the men to eat mashed potatoes with Tabasco hot sauce per their preference. Testosterone levels were checked through saliva tests before and after the testing.
Dr. Daniel Amen says the studies were performed, in part, due to the curry contests that men partake in curry houses in the UK. Male customers try to show their manliness by consuming large amounts of curry, according to the Daily Mail. Testosterone levels have been linked to whether a male is more alpha or dominant, compared to the quieter type of male. It has been proven that the higher levels of testosterone are consistent with the more daring activities, aggression, and extrovert behaviors in men.
The levels of testosterone also affected how the participant perceived the heat of the pepper. This study and others have shown that capsaicin interacts with brain hormones, including those associated with happiness. This same study showed an increase in testosterone in young rats consuming hot sauce prior to puberty which begs the question if that same effect takes place in humans. More studies will be done to prove or disprove that theory.