The Science of Summer
As the temperatures rise and the days grow longer, many people report feeling happier, more energetic, and less anxious. But is there real science behind the "summer mood boost"? Research in psychology, neuroscience, and seasonal affective patterns confirms that summer can positively impact mental health — and the effects are measurable.
Increased Sunlight and Serotonin Levels
One of the most significant mental health benefits of summer is the increased exposure to sunlight, which boosts serotonin, a neurotransmitter associated with mood regulation, sleep, and appetite.
Research shows that serotonin turnover was significantly higher during summer months, correlating directly with the duration of bright sunlight exposure. This helps explain why many individuals experience improved mood, reduced symptoms of depression, and greater motivation during sunnier months.
Key stat: Sunlight exposure can increase serotonin production by up to 50%, helping to alleviate symptoms of anxiety and depression according to the National Institute of Mental Health.
Physical Activity and Outdoor Time
Summer also encourages more outdoor activity and exercise, both of which are powerful tools for improving mental well-being. From hiking in the Rockies to walking around Calgary’s scenic river pathways, warmer weather makes physical movement more accessible and enjoyable.
Regular exercise has been shown to:
Reduce symptoms of depression by 26% (Harvard T.H. Chan School of Public Health)
Improve sleep quality
Decrease levels of the stress hormone cortisol
Spending time in nature further amplifies these effects. A study published in Frontiers in Psychology found that just 20 minutes in a natural environment can significantly lower cortisol levels and improve mood.
Improved Sleep and Circadian Rhythms
The body’s internal clock, or circadian rhythm, is strongly influenced by natural light. In summer, the longer daylight hours help reset this rhythm, leading to improved sleep quality and more restorative rest — both crucial for mental health.
People are also more likely to have consistent wake-sleep schedules during summer, which can:
Reduce irritability
Increase cognitive function
Support emotional regulation
Social Connection and Community Events
Social interaction is a known protective factor for mental health, and summer months offer more opportunities for connection — from festivals to barbecues and outdoor sports. In a city like Calgary, summer events such as the Calgary Folk Music Festival or the Inglewood Sunfest provide accessible ways to engage with community, reducing feelings of loneliness or isolation.
A 2020 meta-analysis in The Lancet Psychiatry found that social connectedness is a stronger predictor of mental well-being than income or employment status.
Vitamin D and Mental Health
Vitamin D, primarily synthesized through sun exposure, plays a key role in brain health. Low levels of vitamin D have been linked to increased risk of depression and seasonal affective disorder (SAD).
According to the Canadian Mental Health Association, 35% of Canadians experience “winter blues,” and 2–3% experience full SAD, most often due to reduced sunlight. Replenishing vitamin D stores in summer has a restorative effect on mood and energy.
Supporting Mental Health Year-Round
While summer brings a natural boost, mental health is a year-round journey. At Mend Psychology, located in Bridgeland, Calgary, our team of licensed psychologists and mental health professionals provides therapy, diagnosis, and support for individuals navigating mood disorders, anxiety, stress, and seasonal changes.