As the cold winter days move to warm summer ones, the thought of relaxing outside in the fresh air is welcoming. My favorite part about summer is being able to just sit outside and enjoy the sunlight hitting my skin, hearing the birds singing around me, and watching the flowers sway in the wind. I always find myself more relaxed after getting fresh air and being outside, and this feeling actually has a scientific explanation. Although we don’t think about it as we enjoy sunbathing on the beach, sunlight actually has many benefits. We grow up hearing about how the sun provides us with vitamin D as a way to encourage us to go outdoors, however vitamin D has a variety of effects on our bodies, and that is not the only beneficial component to sunlight exposure.
The Effects of Vitamin D
Although vitamin D can be obtained through food, its primary source is through the body’s exposure to sunlight. One of the major responsibilities of vitamin D is its benefits to bone formation as it helps to promote calcium and phosphorus absorbance, therefore without vitamin D, bones will not be able to develop properly. College is a time where many people start to focus on their physical health and strength as a large part of their lives. A lot of people will focus on increasing their protein or calcium intake to build their muscles along with starting exercise routines. However, ensuring an adequate amount of vitamin D is another important factor to building muscle, and this can be as easy as spending some time outside in the sun, which is even more convenient as the days get longer and warmer. Along with bone health, vitamin D has effects on cardiovascular health as sufficient vitamin D from sun exposure is associated with a reduced risk of hypertension, diabetes, multiple sclerosis, and cardiovascular disease.
Vitamin D also has effects on mental health, an advantage I hadn’t previously recognized, but when I think about the relaxation I feel after a sunny and warm day, the association makes sense. Long term exposure to moderate levels of sunlight can inhibit the development of depression.
The Effects of Serotonin and Melatonin
Sunlight has other effects on mental and cognitive health through the actions of hormones such as serotonin and melatonin. Serotonin and melatonin are both involved in sleep patterns through the control of circadian rhythms along with influence over cognitive and emotional wellbeing, and these two components fluctuate based on the function of the suprachiasmatic nuclei that is influenced by sunlight exposure. First of all, melatonin sets the stage for your sleeping patterns. Melatonin is produced in dark hours and stops when exposed to daylight, therefore the cycle of melatonin production and suppression is dependent on sufficient exposure to sunlight, especially bright morning light which helps to decrease occurrences of insomnia, premenstrual syndrome, and seasonal affective disorder. Light helps to maintain a consistent sleep schedule, which is especially important for us as college students, it can be difficult to get enough sleep when dealing with a busy school and social schedule, so maintaining regular melatonin rhythms is important so that when we do go to sleep, we are able to sleep restfully. A lack of adequate sleep can be caused by disruption in the melatonin production cycle, therefore causing mental symptoms such as seasonal affective disorder and premenstrual syndrome.
Serotonin is another important factor that is actually the precursor to melatonin and will be converted to melatonin when in dark environments. Serotonin is associated with positive moods and a calm mentality, therefore the production of serotonin due to sunlight exposure can cause positive and relaxing effects. A lack of sunlight would not only lead to less serotonin and influence a person’s mood, but it would also affect melatonin levels and our circadian rhythm due to the relationship between serotonin and melatonin.
Other Factors to Sunlight Exposure
Similarly to serotonin’s beneficial effects on our mood, sunlight exposure also stimulates the increase of endorphins in the body, which is another factor that contributes to the happy feeling we get when walking outside on a sunny day.
Along with making us happier through its control over serotonin and endorphins, sunlight also has a role in making us healthier through its link to the immune system function. Sun can help to increase the number of cytokines. Cytokines help to control the function of our immune cells as they signal them to initiate action when invaders are present and overall aid in the immune system functions. Therefore, the sun can boost the ability of our immune system and keep us healthy.
Sunlight can also increase T cell activity which is active in limiting autoimmune disorders and limits immune reactivity, overall aiding in the body’s immune system and helping it to function to keep us healthy. A good immune system function is an important component in college. In college there are constantly sicknesses being passed from one person to the next, in part due to the close proximity we are to each other, therefore the promotion of the immune system can help us to fight off potential illnesses, while also making the most of our college experience.
Conclusion
When I think about sunlight, I usually just think of how it makes me feel to stand outside on a sunny day and the relaxation and contentment I feel, but I don’t normally consider why I have this feeling. What mechanisms are taking place inside my body to initiate these emotions? Although we don’t tend to think about it, sunlight affects more parts of our body than just our skin.
Sometimes, especially with a busy schedule and cold weather, it can be difficult to get outside and enjoy the sun, and that is why it is helpful to find simple activities and strategies to increase our time outside. For example, exercising outside is a way that I like to increase my time in the sun. Another way to get outside is doing homework or eating outside, especially as the weather gets warmer.
When it comes to sun exposure, I feel like we hear more about the negative effects, and while these do exist, sun exposure has many benefits to the human body, but these benefits only apply in moderation. excessive exposure to sunlight can cause detrimental effects on the skin and it risks photo aging and skin cancer. This is why experts emphasize an intermediate approach to sun exposure and the use of sun protection to attain the benefits of sun exposure while also avoiding possible negative effects on health.