A laboratory study explored the association between variations in testosterone and cortisol hormones level in men and women and their self-reported sexual desire. Results showed that general sexual desires and dyadic sexual desire in women was associated with changes in hormone levels, but this was only the case with the solitary sexual desire in men. The study was published in Adaptive Human Behavior and Physiology.
Testosterone is a sex hormone that plays an important role in the body. Mainly produced in the testes, it stimulates the development of male secondary sexual characteristics, but is also found to regulate sex drive, bone mass, fat distribution, muscle mass, strength, and a number of other physiological characteristics.
Studies have also shown that testosterone levels are associated with status-seeking and various complex psychological behaviors including reproductive behavior and sexual desire. However, the associations between these behaviors and testosterone levels are often not very strong. Due to this, researchers proposed that another hormone – cortisol interacts with testosterone in regulating these behaviors. This hypothesis is known as “the dual-hormone hypothesis”. It posits that cortisol moderates, changes, the effects of testosterone on human behavior and psychological processes including status-seeking.
Study author Kevin A. Rosenfeld and his colleagues wanted to test whether variations in sexual desire of men and women can be explained by the interaction between testosterone and cortisol i.e. by the dual-hormone hypothesis.
The researchers recruited 831 study participants (646 women) using various methods. Many of the participants were students. Of these, 223 (175 women) also participated in the second data collection session. “Most participants attended the initial session in exchange for course credit rather than monetary compensation (US $20), potentially contributing to a minority agreeing to participate in a second session, for which only monetary compensation was offered,” the study authors explained.
Participants were asked to provide their demographic information and recent use of contraception through a questionnaire. They completed assessments of interest in uncommitted sex (the Revised Sociosexual Orientation Inventory, SOI-R) and sexual desire (the Sexual Desire Inventory, SDI-2). Researchers took saliva samples from participants once before and once after they responded to the surveys and used these saliva samples to determine levels of testosterone and cortisol.
Results showed that an interaction between testosterone and cortisol levels within a person predicted the sexual desire in women. This effect was weaker in women who used hormonal contraceptives. In the main analysis these associations were found only in women and were absent in men.
However, additional analysis showed that these interactions between hormones also predicted to a degree certain aspects of sexual desire – dyadic sexual desire in women and solitary sexual desire in men. Dyadic sexual desire represents a wish to engage in sexual activity with another person, while solitary sexual desire represents a wish to engage in sexual activity with oneself, such as in the case of masturbation.
Surprisingly, the finding about the association between the testosterone-cortisol interaction in men was in the opposite direction from that found in some, but not all of, the previous research.
“Some of our results contrast with usual dual-hormone hypothesis predictions of negative interactions between testosterone and cortisol.”, authors conclude. “Although the dual-hormone hypothesis recognizes that several behavioral traits may be inversely moderated by testosterone and cortisol, resulting in the negative interaction effects found in some early work, cortisol’s mechanisms are complex and context-dependent, possibly contributing to seemingly contradictory findings.”
The study sheds light on the association between testosterone-cortisol interaction and certain aspects of human behavior. However, it also has some limitations that need to be taken into account. Notably, researchers did not control how long participants have been awake before participating in the study meaning that natural daily variations in hormone levels could have affected the results.
The researchers also did not control for the relationship status of participants and there are also indications of insufficient stability of the hormone level quantification method used in the study.
The study, “Associations Between Sexual Desire and Within-Individual Testosterone and Cortisol in Men and Women”, was authored by Kevin A. Rosenfeld, Heather Self, Talia Shirazi, Rodrigo Cardenes, Justin Carré, Triana Ortiz, Khytam Dawood, and David A. Puts.