The advantages of sunlight for health
In the United States, approximately 1.5-9% of people may be affected by Seasonal Affective Disorder (SAD), a specific type of depression that worsens during shorter days and improves with longer ones [1]. Beyond producing vitamin D and improving mental health, sunlight offers additional health benefits.
Sunlight triggers the skin to release nitrogen oxides, which dilate blood vessels and help reduce blood pressure [1][5]. This reduction in blood pressure can potentially lower the risk of heart disease. Sun exposure also supports immune regulation beyond vitamin D production [1]. People reporting more sun exposure tend to have lower incidence of heart failure, possibly linked to the blood pressure benefits and seasonal heart disease patterns [1].
Natural light helps reset the body’s internal clock, improving sleep quality and overall circadian balance [4]. This better sleep can lead to a reduced risk of metabolic syndrome, a group of conditions that increase the risk of heart disease, stroke, and diabetes [5].
Sunlight influences certain types of body fat and metabolism via skin-released compounds, lowering risks associated with metabolic syndrome [5]. Moderate sun exposure has been linked with a reduction in metabolic syndrome risk.
While vitamin D supplements have not consistently demonstrated the same breadth of health benefits seen with sun exposure, sunlight may also elevate serotonin levels, further supporting mood and well-being [2][4]. Serotonin is a neurotransmitter that contributes to wellbeing and happiness.
In the northern hemisphere, SAD symptoms are most intense in January and February. Exposure to UVB rays causes human skin to produce beta-endorphins, which reduce pain, promote a sensation of well-being, improve mood, boost the immune system, relieve pain, promote relaxation, help wounds heal, help people feel more alert, increase productivity, and reduce depression [6].
Light therapy, under a medical professional's supervision, is a standard treatment for SAD and can be an effective alternative to sunlight [7]. Antidepressant medications and cognitive behavioural therapy can also be beneficial for people with SAD [3]. Increasing vitamin D intake can reduce SAD symptoms in some cases [8].
However, it's important to balance sun exposure with skin cancer risk awareness. Certain characteristics such as being more susceptible to depression and SAD may put people at higher risk of finding a lack of sunlight hard [6]. Therefore, it's crucial to prioritise mental health and seek help when needed.
References:
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3469324/ [2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3665077/ [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2908559/ [4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3533148/ [5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5723431/ [6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2695468/ [7] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3761405/ [8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5664031/
- In addition to managing Seasonal Affective Disorder (SAD), light therapy can providing an alternative to natural sunlight when needed, as demonstrated by scientific studies.
- Sunlight not only affects the physical health by improving vitamin D production, but also impacts mental health by potentially elevating serotonin levels, contributing to wellbeing and happiness.
- Apart from the better sleep quality and reduced risk of metabolic syndrome, sunlight also influences certain body fat and metabolism via skin-released compounds, potentially lowering risks associated with metabolic syndrome.
- Mental health supplements, such as those that increase vitamin D intake, can help reduce the symptoms of SAD in some cases, as supported by research.
- An imbalance in susceptibility to depression and seasonal affective disorder (SAD) may make some individuals more vulnerable to experiencing adverse effects from a lack of sunlight exposure, highlighting the importance of mental health and well-being.
