Alfred Kinsey caused widespread shock in 1948 when his surveys of sexual behavior revealed what was happening behind bedroom doors. This year, researchers from Kinsey’s institution (Indiana University) updated his work, and this time the surprise is about what is not happening.

The new survey asked over 4,000 US adolescents and adults about their sexual behavior in 2009 and polled them again in 2018. Nearly all forms of sexual activity declined over the intervening decade, particularly among adolescents and young adults: penile-vaginal intercourse, oral sex, anal sex, and mutual masturbation. Only solo masturbation held steady, and only among adults (ages 18–49), three out of four of whom had masturbated alone in the past year. Adolescents (ages 14–17) reported a steep decline in solo masturbation: 61% had not masturbated in the past year in 2018, compared to 44% in 2009. The percentage of adolescents who reported no sexual activity (including no masturbation) rose from 29% to 43% among young men and from 50% to 74% among young women (Herbenick D et al, Arch Sex Behav 2022,51(3):1419–1433).

The decline has been documented by similar surveys in the US, UK, Australia, Germany, and Japan, and seems to have begun in the early 1990s. What’s new in the current data is the drop in adolescent masturbation, suggesting that sexual desire itself may be waning. In line with that, most teens and adults who are not having sex feel no discontent about their situation, even if they had been sexually active in years past, according to a UK study (Ueda P and Mercer CH, BMJ Open 2019;9(10):e030708).

As to the cause of these trends, we can only speculate. Gender identities have expanded and more adolescents identify as asexual. Alcohol use is on the decline in youth and respect for sexual consent is on the rise. Young adults are less likely to marry and less likely to seek romantic relationships than they were in the past. Screen time, social media, and serotonin reuptake inhibitors have increased in parallel with these trends, as has exposure to endocrine-disrupting chemicals from pesticides, cosmetics, and processed foods.

The Kinsey Report helped normalize behaviors that were previously taboo, including masturbation, homosexuality, and extramarital sex. Therapists often quoted those surveys to reassure patients who were anxious that their sexual practices were a form of mental illness. As asexuality moves closer to the center, today’s surveys may offer solace to patients who feel alone in their lack of sex. At the very least, they can help us better understand our patients.