Fathers who spend several months at home caring for their young children may be protecting more than family bonds—they could also be safeguarding their own mental health, according to new research from Sweden.

A study conducted by researchers at Karolinska Institutet and published in the American Journal of Public Health found that fathers who took between 14 and 40 weeks of parental leave were significantly less likely to experience symptoms of depression during the first years of their child's life than fathers who took four weeks or less.

The findings arrive at a time when many countries are debating how to best support families, improve mental health, and encourage fathers to take a more active role in childcare. While previous research has largely focused on mothers' well-being after childbirth, much less attention has been paid to the mental health of fathers, despite growing evidence that many new dads also struggle with emotional stress, anxiety, and low moods.

To investigate the issue, researchers followed 746 Swedish fathers over an 18-month period. The men filled out questionnaires when their babies were about nine months old and then again when the babies were about 27 months old. The team also found out how much time off each father had taken from work to care for their child.

Importantly, the researchers adjusted their analysis to account for factors that could influence both leave-taking and mental health. These included fathers' mental health at the beginning of the study, family circumstances, economic conditions, and the amount of parental leave used by mothers.

The results showed an obvious pattern. Fathers who took between 14 and 40 weeks of leave were less likely to report depressive symptoms—feelings such as persistent sadness, hopelessness, low energy or a lack of interest in everyday activities—than those who took four weeks or less.

However, the same benefit was not observed among fathers who took only five to 13 weeks of leave. Nor was it seen among those who took more than 40 weeks when compared with the shortest-leave group.

In Sweden, each parent is entitled to 90 non-transferable days of parental leave, equivalent to roughly 13 weeks. The study suggests that benefits may emerge when fathers spend even more time at home with their children.

“Our results suggest that fathers who take parental leave beyond the 90 days, but not more than 60 per cent of the total leave, may have better mental health,” said Michael Wells, a docent at the Department of Women's and Children's Health at Karolinska Institutet, who conducted the study together with Jingyi Wang.

Researchers believe one possible explanation is that sustained time at home helps fathers develop a closer relationship with their child. Daily caregiving can build confidence, establish routines, and make dads feel more secure in their parenting roles. Those experiences may act as a buffer against emotional difficulties during the demanding early years of raising a child.

The findings align with earlier studies from Nordic countries, Canada, and parts of Europe, which show that fathers who are more involved in childcare often report stronger parent-child relationships, lower stress levels, and greater family satisfaction. Some research has also suggested that active father involvement can benefit children's emotional and cognitive development.

Still, the researchers urge caution. Because the study was observational, it cannot prove that longer parental leave directly caused better mental health. Furthermore, fathers who may have been already coping better emotionally were more likely to take extended leave. Another limitation is that information on parental leave was based on fathers' own reports rather than administrative records.

The study was carried out in collaboration with the Hong Kong University of Science and Technology, adding an international dimension to a question that is becoming increasingly relevant worldwide.

As governments search for ways to improve family wellbeing and address rising mental health concerns, the research offers a thought-provoking message: giving fathers meaningful time at home may not simply benefit children and partners. It may also help fathers themselves navigate one of life's most significant transitions with greater confidence, stability and emotional resilience.