There may indeed be some truth to the idea of summer sadness — at least when it comes to men. A study found that men born in the summer are more prone to depression than men born in other seasons.

Researchers at Kwantlen Polytechnic University in British Columbia, Canada, conducted the study, which was an international survey of adults. They found that men, but not women, are more likely to experience symptoms of depression later in life if they were born in the summer compared to other seasons.

The results show that mothers are exposed to important environmental risk factors that vary throughout the calendar year, including levels of sunlight.

The author of the study, Mikael Mokkonen, was inspired to explore this topic by a simple question asked at a party.

"The initial spark for the idea for this study came when someone asked me if I believed in horoscopes. It made me wonder if there could be a biological basis for them, in terms of how a person's birthday might be linked to physiological or psychological characteristics," he told Gizmodo.

Doctors have long known that seasonality can affect our mental health—the most striking example of this is seasonal affective disorder, a type of depression that typically occurs during the winter months (although a summer form also exists). But the link between time of birth and mental health has been relatively understudied, Mokkonen noted.

Mokkonen and his team conducted an online survey of 303 adults. Participants provided basic demographic information such as age and answered two questionnaires commonly used to assess a person's level of anxiety and depression.

After controlling for factors such as age and income, the researchers found that men born in the summer were significantly more likely to report symptoms of depression than men born in other seasons.

The results of the team's study were published in the journal PLOS Mental Health.

This type of study can only show a correlation between two things (in this case, seasonality of birth and depression), but cannot conclusively prove that being born in the summer can affect men's mental health.

The researchers also acknowledge that they collected the survey responses over a short two-month period in early 2024, which means they may not have been able to capture people's "differences in depression and anxiety scores."

In addition, a large proportion of the participants were students, which calls into question the representativeness of the sample.

Mokkonen emphasized that seasons have long played a role in the survival of most species. And although humans today are generally more protected from the harsh elements of the outside world than our prehistoric ancestors, the changing aspects of the seasons may still be enough to influence us in subtle ways as we develop in the womb.

"I would say it's probably related to the mother's environmental conditions during pregnancy. Think about conditions such as temperature and sunlight — how do these conditions vary throughout the year?" the scientist said.

The researchers plan to continue investigating how other factors, including the mother's diet and blood hormone levels, may influence their children's later health.

Mokkonen also pointed out that regardless of the season in which they were born, the majority of people in the study reported having at least some symptoms of anxiety (66%) and depression (84%). In other words, although the seasons have some influence on us, some things are unfortunately common to everyone. | BGNES