By Dr. Justin Lehmiller
Sex has a lingering effect on our feelings of happiness, according to a new study published in the journal Psychological Science. This phenomenon, known colloquially as sexual afterglow, isn’t a new idea; however, it’s one that scientists haven’t really studied until now. This new study offers insight into how long sexual afterglow lasts, as well as why it exists in the first place.
Researchers from Florida State and UCLA analyzed data from two sets of couples who took part in a two-week diary study. One sample included 96 couples from Texas, while the other included 118 couples from Florida. All participants were in their first marriages, they were all newlyweds (none were married longer than 4 months), and virtually all of them were heterosexual. Each participant completed a daily survey that asked not just whether they had sex that day, but also how sexually satisfied they felt and how satisfied they were with their marriage.
During the 14 days of the study, couples had sex four times on average, though some did not have sex at all while others had sex every day. It turned out that having sex was linked to greater feelings of sexual satisfaction on the day it occurred.
However, sex also predicted sexual satisfaction on the days immediately after. Specifically, sex was associated with higher levels of satisfaction for the next two days, but it not predict satisfaction three or more days later. This tells us that the sexual afterglow-defined here as the post-sex bump in sexual satisfaction-seems to last about 48 hours.
On a side note, perhaps this is why the most common frequency of sex among young married couples is 2-3 times per week. This intermittent frequency of sex-and the afterglows that ensue-may help to maintain an optimal level of happiness.
So what causes the afterglow effect, and why does it occur? These data don’t allow us to say with certainty; however, the researchers believe that it has to do with biological changes that occur during sex, particularly the release of certain neurotransmitters and hormones (namely, dopamine and oxytocin). These brain chemicals are thought to temporarily boost feelings of satisfaction. This boost, in turn, is thought to be adaptive in the sense that it promotes the bonding necessary to help to sustain a relationship. As some support for this idea, the participants who experienced the strongest afterglows reported the highest levels of satisfaction during a follow-up survey carried out a few months later.
A major strength of this study is that the researchers replicated the same pattern of effects in two different samples; however, there are some important limitations. For one thing, given that most participants were heterosexual and had only been married a short time, it is unclear whether these results would generalize to same-sex couples or couples who have been together much longer.
While we must await further research to learn more, these findings are important because they confirm that a sexual afterglow does indeed exist and, for the first time, we now have some sense as to how long these effects typically last.
Meltzer, A.L., Makhanova, A., Hicks, L.L., French, J.E., McNulty, J.K., & Bradbury, T.N. (2017). Quantifying the sexual afterglow: The lingering benefits of sex and their implications for pair-bonded relationships. Psychological Science.
Dr. Justin Lehmiller is an award winning educator and a prolific researcher and scholar. He has published articles in some of the leading journals on sex and relationships, written two textbooks, and produces the popular blog, Sex & Psychology. Dr. Lehmiller’s research topics include casual sex, sexual fantasy, sexual health, and friends with benefits. He is currently the Director of the Social Psychology Graduate Program and an Assistant Professor of Social Psychology at Ball State University.