Sunlight — The Natural Supplement For Our Mental Health
By: Jerren Gan
Tags: Self Improvement, Mental Health, Health, Wellness, Science

Sunlight — The Natural Supplement For Our Mental Health

The science behind how the sun is related to our mental wellbeing

Photo by Rampal Singh on Unsplash

Yoga, meditation, binaural beats, aroma therapy. All of these are our attempts at improving our mental health. More than ever, this generation has spoken out about mental health issues and have taken considerable steps in order to try and improve our mental health.

Yet, amongst the many techniques that seem to be popular, it’s surprising that being under the sunlight isn’t something that everybody does.

After all, it’s completely free and can be done easily (at least when it isn’t winter).

Sunlight and Serotonin

Experts often associate exposure to sunlight with the release of serotonin. And this has been proven by science.

A study conducted to find the relationship between serotonin, sunlight, and the season found that the rate of serotonin production is directly related to the prevailing duration of bright sunlight. At the same time, as the luminosity of the sunlight increased, the rate of serotonin production also rose rapidly.

Furthermore, it has been reported in Times that autopsy studies found higher levels of serotonin in individuals that passed away in summer than those who did in winter. This difference in serotonin level was attributed to the differing amounts of sunlight available between the two different seasons.

So… exposure to sunlight is associated with the release of serotonin. But what does that have to do with mental health?

Serotonin (also known as 5-hydroxytryptamine) is actually a neurotransmitter and is known as the natural ‘feel-good’ chemical. This is due to its role as a natural mood stabilizer and its ability to reduce the symptoms of depression.

As such, by increasing the rate of serotonin production, sunlight acts as a natural mood booster, allowing one to feel happier while reducing the negative effects that are often associated with depression.

In fact, in 2018, a study conducted by Chinese researchers found that moderate exposure to sunlight correlates to an improvement in memory and motor learning in mice. While humans might function differently from mice, this study suggests that a similar relation could be happening for us.

Additionally, results from another study also suggested that exposure to sunlight is associated with the cognitive decline one experiences. In this study, the researchers found that individuals with a decreased exposure of sunlight experienced a higher probability of cognitive decline. This was especially true for individuals with existing depression.

Sunlight and Melatonin

Apart from serotonin, sunlight plays a key role in the release of another chemical — melatonin. However, instead of being produced when it is sunny, melatonin is produced when it is dark. The lower the light intensity, the more melatonin secreted.

While serotonin is a feel-good chemical, melatonin is the natural hormone that promotes sleep in our bodies. As it becomes dark, our body secretes more melatonin in order to prepare us for sleep. This means that melatonin is essential to help us regulate our sleep cycles.

However, there is evidence that suggests that shift workers who work through the night (and as such, are less exposed to sunlight) produce less melatonin. Without this sleep producing hormone, one could possibly experience insomnia and low quality sleep from sleep disturbances.

As quality sleep is key to maintaining a healthy mind, exposing yourself to sunlight can help encourage your body to create melatonin, allowing you to get a good night’s rest (and an improved mental state).

Furthermore, normal melatonin secretion is key to maintaining our bodies’ natural circadian rhythm. As a disruption of the natural circadian rhythm is known to increase the risk of depression, going under the sun to maintain healthy levels of melatonin production could be key in helping you keep depression at bay.

Lack of Sunlight Leaves You SAD

With sunlight playing key roles in the creation of serotonin and melatonin, a lack of sunlight can actually lead to a condition called Seasonal Affective Disorder (SAD).

SAD is actually a form of depression that typically affects individuals during the winter seasons (explaining the lethargy and helplessness you might feel when winter comes). While sunlight is not the only factor, it is suggested that SAD primarily affects individuals in winter as one is less likely to be exposed to strong sunlight. And this points to the importance of sunlight exposure. In order to help reduce the possibility of SAD (especially when it isn’t even winter yet), try your best to expose yourself to natural sunlight as much as possible. Who knows, that might just be the key to helping you keep illnesses like SAD at bay.

Sunlight and Vitamin D

Apart from serotonin and melatonin, sunlight plays a key role in helping our bodies synthesize vitamin D. A fat-soluble vitamin, vitamin D promotes calcium absorption (strengthening your bones) while also supporting the immune system.

A lack of vitamin D in one’s body actually increases the risk of osteoporosis, jaundice, and cardiovascular diseases. As physical well being is tied closely to one’s mental health, getting a healthy dose of vitamin D helps protect your mental wellness by maintaining your physical health.

Besides physical health, vitamin D also has a surprising role in mental health as well. Researchers have found that when one has a vitamin D level of below 20 nanograms per millimeter, the risk of depression is raised by as much as 85 percent when compared to individuals with vitamin D levels of more than 30 nanograms per millimeter).

Studies done also suggest that there is a casual relation between taking vitamin D supplements and an improvement in symptoms for those who suffer from depression. As few foods offer vitamin D naturally, going out into the sun might be the best (and easiest) way to help your body get enough vitamin D.

But How Much Sunlight is Enough?

Of course, we’ve all heard warnings that tell us not to go out into the sun. As sunlight is made up of ultraviolet (UV) rays, experts often warn us about prolonged exposure to strong sunlight.

After all, UV rays damage our skin cells, promoting the formation of blemishes and wrinkles while increasing the risk of skin cancer.

However, Dr. James O’Keefe, a cardiologist who studies the relationship between vitamin D and cardiovascular health, believes that we are evolved to be in the presence of direct sun exposure, claiming that having some direct sunlight helps benefit our health greatly.

In fact, WHO has published guidelines regarding the amount of sunlight exposure we should have. With the beneficial effects of sunlight exposure, WHO suggests getting 5–15 minutes of unblocked (e.g. no sunscreen, no long sleeves) sunlight on our face, arms and hands 2–3 times a week.

With more and more of us spending an increased number of time indoors, going out for occasional sunlight exposure can greatly help improve your mental health.

Of course, as UV rays can still cause your skin harm, do keep your direct sunlight exposure short and avoid periods with strong UV radiation (e.g. noon). If you are going to be out in the sun for an extended period of time, protect yourself with sunscreen. And for those with skin conditions, it might be good to ask your doctor for advice before heading out to bask in the sun.