Impact of Sunshine on Happiness
When the sun is shining, it can feel like our mood lifts. We love to get outside, soak up the sunshine and enjoy the world around us. But how and why does sunlight affect our mood?
In a modern world where we spend so much time indoors, human beings are still biologically programmed to benefit from the natural exposure to daylight. Exposure to sunlight affects the production of certain hormones, which help us to regulate our natural body clock, known as circadian rhythm. Sunshine triggers the production of serotonin, which is our “happy hormone”. Reduced exposure to sunlight can lead to increased melatonin production, which makes you feel sleepy. The right balance of these hormones promotes wakefulness and focus during the day, and allows us to sleep better at night. Regular, good quality sleep is strongly linked to a positive mood and improved focus and productivity – check out our other blogs on sleep for more details.
Positive Psychology teaches us that enjoying spending time outside and in nature helps us to feel vitalised and energetic. Studies also demonstrate that exposure to sunlight and the use of outdoor green spaces have a positive impact on mental health.
Seasonal Affective Disorder
We know that exposure to sunlight leads to improved mental health, so what happens when people don’t spend time in natural light? Seasonal Affective Disorder (SAD) is depression which changes in line with the seasons. This is particularly common in countries where there is a lot of variation in daylight hours between seasons, most commonly with people becoming low in mood during winter months and feeling better during summer months.
The symptoms of SAD are similar to those of depression, and include persistent low mood, feeling irritable, losing interest in activities, feeling lethargic and struggling to get up in the mornings. The main treatments for SAD are lifestyle changes, such as regular exercise and exposure to direct sunlight where possible, counselling or CBT, anti-depressants or light therapy.
Additionally, sunlight also plays a vital role in the body’s production of Vitamin D, which is known as “sunshine vitamin”. Vitamin D is important for our physical health, in particular the health of our bones, muscles and teeth and has a role in maintaining a healthy immune system. Not getting enough Vitamin D can result in physical symptoms, such as generalised aches and pains, feeling tired and lacking in energy.
Whilst some studies demonstrate that people with depression are more commonly found to have low levels of Vitamin D, unfortunately there is no evidence suggesting that supplementing Vitamin D can cure or improve depression. However, treating low Vitamin D can have a positive impact on energy and improving aches and pains.
So, what are you waiting for? Get outside and embrace those rays (using SPF!). Why not start with a simple change, like walking to work, taking your lunch break outdoors or having your morning coffee in the morning sun?
Influence of External Natural Environment Including Sunshine Exposure on Public Mental Health: A Systematic Review. Psychiatry Int. 2022, 3(1), 91-113; https://doi.org/10.3390/psychiatryint3010008
Anglin RES, Samaan Z, Walter SD, McDonald SD. Vitamin D deficiency and depression in adults: Systematic review and meta-analysis. The British Journal of Psychiatry 2013;202:100-7
Gowda U, Mutowo MP, Smith BJ, Wluka AE, Renzaho AMN. Vitamin D supplementation to reduce depression in adults: Meta-analysis of randomized controlled trials. Nutrition 2015;31:421-9. [PubMed abstract]