People generally agree that a happy romantic relationship is also a sexual one, but past research hasn’t made clear how much sex, exactly, is best. Does sex have a limitless effect on happiness, as in, the more sex you have the happier you are? Or is there a cap after which the stress from trying to hit a certain number cancels out any happiness benefits the sex confers?
Proponents of daily sex challenges -- and there are a surprising number of these challenges, in which spouses commit to a roll in the hay every day for a certain period of time -- claim daily sex can recharge desire and make for a happier marriage.
While this approach may have worked for some couples (notably, the ones who wrote books about it), new research suggests that there are limits to how much happiness is linked to sex. New research published in the journal Social Psychological and Personality Science found that once couples are having sex about once a week, personal happiness and happiness in the relationship begins to level off.
Lead author Amy Muise, a sex and romance researcher at the University of Toronto Mississauga, says it’s a good reminder for couples not to feel pressured to live up to a certain “number” when it comes to sex frequency.
"In general it is important to maintain a sexual connection with a romantic partner, but it is also important to have realistic expectations for one’s sex life, given that many couples are busy with work and responsibilities,” she told HuffPost. "Our research suggests that engaging in regular sex is associated with happiness, but it is not necessary, on average, for couples to aim to engage in sex as frequently as possible."
What research says about sex and happiness
To see if the happiest couples were also the ones having the most sex, Muise conducted three studies. The first, which drew data from a 23-year study of over 25,000 people, found that more sex is linked to higher levels of happiness, but only until the frequency reaches about once a week. However, this relationship between happiness and sex held true only for people in relationships; for singletons, the statistical relationship between sex and happiness was not significant.
The second, in which Muise recruited 335 ethnically diverse participants in an online survey, confirmed the first study's results. But to put the sex-happiness relationship in context, she also decided to see how much of an effect annual household income had on participants’ general happiness. She found that the happiness difference between monthly sex and weekly sex was actually more dramatic than the happiness difference between earning $15,000-$25,000 and earning $50,000-$75,000. In other words, weekly sex paid off more in happiness than actually getting paid more.
The final study, which included data from a 14-year study of 2,400 married couples, again found that sex was linked to higher levels of satisfaction with the relationship, but only until they had sex about once a week.
Don't feel bad about your 'number'
Several long-term studies suggest that once-a-week sex actually is the norm for most established couples. Muise says there's no research about whether couples are happy about this, or if the couples even know this is the average frequency. One possible explanation for this number is that people might intuitively feel that any more sex would just result in diminishing returns, but that has yet to be tested, Muise explained.
People have tested sex frequency's impact on happiness experimentally. For a 2015 paper, researchers recruited 128 couples, divided them randomly and then asked one group of couples to double their sexual frequency, while asking the other couple group to continue as usual. The couples who doubled their pleasure didn’t report any greater levels of happiness. In fact, they actually experienced less happiness, and their enjoyment of sex went down.
At the time, the researchers suggested that being told to have more sex may be what detracted from the experience, but Muise points out that the couples in the study were already having sex, at baseline about once a week, before being asked to double it.
For couples struggling to juggle work, children and other responsibilities, the misconception that they’re not having “enough” sex could be daunting or stressful. Muise's findings, on the other hand, suggest that "people may be able to engage in sex frequently enough to maximize their well-being without aiming to engage in sex as frequently as possible," as she says.
Based on her findings, she suggested a re-write of that famous John Updike quip: "Sex may be like money -- only too little is bad."
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