Infidelity has long been a topic of interest to scientists who study sex and relationships. Over the years, they’ve uncovered a number of surprising things about who’s likely to cheat, why people do it, and the effects that it can have on us and on our relationships. Here’s a look at ten of the most interesting things scientists have discovered to date on the topic of cheating.

1.) Research has found that certain physical traits and characteristics are linked to infidelity. For instance, men with larger testicles and higher levels of testosterone are more likely to cheat [1]. Some scientists have suggested that there may be an evolutionary reason for this: having these traits could offer guys a competitive edge over other men when it comes to passing along their genes because higher testosterone stimulates more sexual desire, thereby reducing the odds of missing out on potential reproductive opportunities.

2.) Studies have found that when people in monogamous relationships cheat, most of them don’t use condoms during the act. Cheating is therefore a very high-risk behavior for contracting and spreading STIs.

3.) Despite the arrival of Ashley Madison and other websites designed to facilitate infidelity, the prevalence of cheating isn’t any higher today than it was 20 years ago. In other words, it doesn’t seem to be the case that these new technologies have encouraged more people to cheat—rather, they’ve just given would-be cheaters an easier way to do the deed.

4.) The frequency with which heterosexual women have orgasms with their partners does not predict women’s likelihood of cheating; however, the frequency with which women fake orgasms does. That is, the more a woman fakes orgasms with her partner, the more likely she is to cheat on him.

5.) People don’t agree at all on what “cheating” actually means. Not everyone thinks that sexual contact with someone outside of their relationship constitutes cheating; in contrast, others think that just talking to another person or having dinner with them can be a form of cheating. Research finds that men and women define cheating in different ways and, further, that what we think of as cheating also depends upon our attachment style. Learn more here.

6.) Research has found that men and women are more likely to have affairs just before beginning a new decade of life. In other words, when we’re at an age that ends in a nine, we seem more inclined to cheat. Learn more about why in this article.

7.) There is some truth to the old saying “once a cheater, always a cheater,” because research has found that a majority of people who admit to infidelity say they’ve done it more than once. However, this isn’t true across the board. Whether a cheater is likely to cheat again depends upon their reasons for cheating in the first place.

8.) It’s common to have fantasies about cheating on your partner. In fact, studies have found that almost all men (98%) and the vast majority of women (80%) report fantasizing about someone other than their current partner at least occasionally.

9.) When affairs are discovered, it doesn’t always mean the end of a relationship or marriage. In fact, studies have found that some relationships actually emerge stronger from such revelations than they were before. Check out this article to learn more.

10.) The risk of having a heart attack during sex is very low; however, research has found that when heart attacks do occur during sex, they’re more likely to happen to men when they’re cheating compared to when they’re having sex with a spouse [1]. Why? Some scientists have argued that cheating induces psychological distress (e.g., by creating feelings of guilt, anxiety, or stress) that, in turn, can have a negative effect on cardiovascular function.

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[1] Fisher, A. D., Bandini, E., Rastrelli, G., Corona, G., Monami, M., Mannucci, E., & Maggi, M. (2012). Sexual and cardiovascular correlates of male unfaithfulness. The Journal of Sexual Medicine, 9(6), 1508-1518.

Image Source: 123RF.com/asife

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