Earlier sexual debut may shape aging later in life

Age at first sexual intercourse may be more than a milestone in adolescence. A new study in Healthcare and Rehabilitation suggests that it may also be linked to how people age later in life.

A team of investigators from Shandong University examined whether age at first sexual intercourse was related to several aging outcomes, including overall aging profile, longevity, parental lifespan, frailty, healthspan, and self-rated health. To do this, they used Mendelian randomization, a method that uses naturally occurring genetic differences to help test likely cause-and-effect relationships.

The researchers found that a genetic tendency toward earlier first sexual intercourse was associated with a less favorable multidimensional aging profile, shorter longevity-related measures, and higher frailty.

"We then explored why this link might exist. Among 145 possible mediators, 34 met the criteria for further analysis," shares first author Kaixian Wang. "Frailty index, miserableness, chronic obstructive pulmonary disease, and attention-deficit/hyperactivity disorder appeared to play especially important roles."

From a life-course perspective, early behavioral events may leave long shadows on later health. "Our findings suggest that the timing of first sexual intercourse may be connected to aging through multiple psychological, behavioral, and disease-related pathways," says Wang. "Nonetheless, our findings do not mean a single behavior determines a person's future health. Instead, they highlight how early-life experiences may cluster with mental health challenges, chronic disease risks, and functional decline over time."

"Prevention and intervention across the life course may help reduce later health disadvantages and promote healthier aging," says corresponding author Long Sun. "Our findings further affirm the value of early sexual health education and broader support for adolescents who may be at higher risk."

The researchers acknowledged that the study was based mainly on genetic data from people of European ancestry, and highlighted the need for further research in other populations.

Contact author:

Long Sun

Department of Social Medicine and Health Management, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan 250012, China

Email: sunlong@sdu.edu.cn.

Funder:

This research was supported by the National Natural Science Foundation of China (72574129) and the Humanities and Social Sciences Fund of the Ministry of Education of China (24YJAZH134).

Conflict of interest:

The authors declare no competing interests.

See the article:

Wang, K., He, Y., Yu, M., Shao, Z., Wei, Z., Xu, Y., Qi, Y., Wang, W., Li, X., Ren, X., & Sun, L. Evidence for the causal relationship between age at first sexual intercourse and multidimensional aging phenotypes from a full life cycle perspective: A Mendelian randomization study. Healthcare and Rehabilitation, Volume 2, Issue 1, 2026, 100064. https://doi.org/10.1016/j.hcr.2026.100064