Seven Things Science Has Taught Us About Infidelity

There is a massive body of scientific research on cheating and infidelity focused on how common it is, who does it, and why it occurs. A recent review paper on the subject, in press at the journal Current Opinion in Psychology, offers a glimpse into some of the more interesting findings that have emerged over the years. See below for a brief taste, but check out the full paper for more, along with a set of helpful suggestions for improving future research on this topic.

1.) In any one-year period, it is estimated that 2-4% of spouses engage in sexual infidelity.

2.) Cumulatively, researchers estimate that infidelity occurs in 20-25% of marriages at some point.

3.) Infidelity—just like sexual behavior in general—changes with the seasons. Specifically, infidelity peaks in the summer. Why? Perhaps because people travel more in the summer and, to the extent that they travel separately from their partners, the distance might provide more opportunities to cheat discreetly.

4.) Infidelity rates skyrocketed between 1991-2006, especially among men aged 65+. Why? Scientists speculate that this may have been tied to the introduction of Viagra and other ED drugs, which really took off during this same time period.

5.) Whereas previous research suggested that cheaters were far more likely to be male than female, recent research has found that the gender gap is closing. In fact, among adults under age 45, rates of infidelity are almost identical across the sexes.

6.) Children of parents who cheated are actually twice as likely to cheat themselves as adults.

7.) Cheating is more common among couples in which one partner is employed and the other stays at home compared to couples in which both partners are employed.

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To learn more, see: Fincham, F. D., & May, R. W. (2017). Infidelity in romantic relationships. Current Opinion in Psychology13, 70-74.

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