A reader submitted the following question:

“Is it true that gay men have bigger penises than straight men?”

While some research suggests that there might indeed be some truth to this idea, the findings warrant a hefty dose of caution. Here why:

The main study cited as support for the idea that gay men are more well endowed that heterosexual men was published in 1999 in the Archives of Sexual Behavior. What the authors of this study did was analyze data collected by the Kinsey Institute between the years 1938 and 1963.

Specifically, they looked at data from 5,122 men, of whom 935 were classified as homosexual and 4,187 were classified as heterosexual on the basis of their sexual behaviors.

Measurement data were available for both flaccid and erect penile length and girth, as well as men’s own estimated erect penile length. Participants had taken the measurements themselves and mailed them to the Institute.

Across all five dimensions, gay men had significantly larger penises. Most notably, the measured erect length for gay men was 6.46 inches, compared to 6.14 inches for straight men. Measured erect circumference was 4.95 inches for gay men, compared to 4.80 inches for straight men.

The authors of the study took their findings as evidence in favor of a biological explanation for homosexuality. Specifically, the thought is that perhaps there is a testosterone “surge” that occurs at some stage of development that accounts for the observed difference in penis size.

Although provocative, there are some important caveats to these findings. While this sample was large, it’s important to keep in mind that the data were collected more than a half-century ago and that the men who participated were not representative of the U.S. population.

In addition, all measures were obtained from men’s own self-reports. As a result, there was plenty of room for error and, potentially, exaggeration. Could it be that gay men exaggerated their penis sizes more than straight men? Alternatively, might it be possible that gay men were more aroused when they took their measurements, thereby leading to larger numbers? The data don't allow us to rule out these and other alternative explanations.

So, while there is some research to suggest that gay men have larger penises than straight men, it would be very helpful to replicate this finding using using more reliable methods and more representative samples before drawing firm conclusions.

Want to learn more about Sex and Psychology ? Click here for previous articles or follow the blog on Facebook (facebook.com/psychologyofsex), Twitter (@JustinLehmiller), or Reddit (reddit.com/r/psychologyofsex) to receive updates.

To learn more about this study, see: Bogaert, A. F., & Hershberger, S. (1999). The relation between sexual orientation and penile size. Archives of Sexual Behavior, 28(3), 213-221.

Image Credit: iStockphoto.com

You Might Also Like: