Optimal sexual frequency may exist and help mitigate depression odds in young and middle-aged U.S. citizens: A cross-sectional study.

Background: While sexual activity is known to benefit physical health, its connection to psychological well-being is less studied. We hypothesized that lower self-reported sexual frequency would be independently associated with higher odds of depression, as assessed by the Patient Health Questionnaire-9 (PHQ-9).

Methods: We included 15,794 U.S. adults aged 20-59, reporting sexual frequency and complete PHQ-9 scores, from the National Health and Nutrition Examination Survey (2005-2016). Logistic regression models evaluated the independent association between sexual frequency and depression, while restricted cubic spline models explored potential non-linear associations.

Results: The analysis revealed a significant negative association between sexual frequency and the odds of depression. Compared to those engaging in sexual activity less than once per month, participants reporting sexual activity once per month but less than once per week (OR: 0.58; 95 % CI: 0.48-0.70) and at least once per week (OR: 0.6; 95 % CI: 0.51-0.69) had lower odds of depressive symptoms. The restricted cubic spline model indicated a saturation effect (P for nonlinearity = 0.002), suggesting an optimal sexual frequency of 52 to 103 times per year (1-2 times per week) to reduce depression odds.

Conclusion: We revealed a significant negative association between self-reported sexual frequency and the odds of depression. A sexual frequency of 1-2 times per week showed the greatest protective effects on psychological well-being and may serve as a reference standard for mental health evaluation and monitoring during depression treatment. Further research is needed to determine directionality, causality, and potential modifiers of this association.