Discover the Health and Wellness Benefits of Sunlight Exposure

Last Updated on 07/20/2024 by Jonathon

We’ve all seen the typical advice when it comes to sun exposure; cover up, put on sunscreen, limit your exposure to harmful UV rays… but did you know that exposure to sunlight isn’t all bad? In fact, recent evidence suggests that sun exposure reduces all-cause mortality (the risk for death), while there has been no strong evidence that excessive exposure reduces the human lifespan (Weller 1-2). Sunlight exposure plays a crucial role in our overall health and wellness, as it has myriad benefits for the human body. The benefits of sunlight exposure include improving our energy and mood, enhancing our immune system, regulating sleep cycles, and even strengthening bone through vitamin D synthesis.

The Science Behind Sunlight, Energy and Mood

Are you tired of feeling sluggish and reaching for that extra cup of coffee to get through the day? It’s time to embrace a natural source of energy that’s right at your fingertips: sunlight. So, let’s explore the energizing benefits of sunlight and how you can harness its power to fuel your day.

Have you ever noticed how a sunny day instantly energizes your body and uplifts your mind? There’s a scientific reason for that. Sunlight is a rich source of vitamin D, often referred to as the “sunshine vitamin,” which plays a crucial role in regulating our energy levels and mood, and sunlight exposure has been linked to less depressed mood in office employees (An et al 4, 10).

Many of us might not realize the intricate ties between vitamin D and our daily energy levels. This remarkable nutrient, primarily obtained from sunlight exposure, acts much like a key: unlocking our body’s energy reserves. It influences the efficiency with which our cells convert food into fuel, significantly impacting our vitality.

To get a little more scientific (for those of you who like that kind of thing), the relationship between vitamin D and energy levels is rooted deeply in our biochemistry. Vitamin D receptors are widespread across brain regions involved in mood regulation, indicating its integral role in mental health and well-being. In the realm of energy, vitamin D facilitates the mitochondrial function, the powerhouse of the cell, enhancing the body’s ability to produce ATP (adenosine triphosphate), the currency of energy in biological systems. This process is vital for staving off fatigue and boosting energy levels.

Vitamin D also extends its influence within the body to insulin regulation, assisting in maintaining optimal blood sugar levels through its actions on insulin secretion and sensitivity (Bikle 6, 36). This can have a direct impact on our overall energy levels as well as mood stability.

Furthermore, vitamin D plays a significant role in the synthesis of serotonin (often dubbed the “happy hormone”), a neurotransmitter associated with mood, appetite, and sleep. Adequate sunlight exposure can elevate serotonin levels, promoting a more positive mood and a vibrant energy state, further combating feelings of fatigue and lethargy, and leaving you feeling more refreshed and revitalized (An et al 4). 

This interplay between vitamin D, energy, and our mood might explain why sunny days often bring a noticeable uplift in our spirits. By stepping into natural light, we’re not just soaking in warmth but essentially energizing our bodies and minds in a profoundly natural way.

How Sunlight Acts as a Catalyst for a Stronger Immune System

The immune system is our body’s ultimate defense against illness and disease, making it crucial to keep it strong and functioning optimally. For this reason, sunlight exposure can play a significant role in supporting our immune response.

Exposure to sunlight triggers the production of vitamin D, which is essential for maintaining robust immunity. Vitamin D has been shown to regulate various genes involved in the immune response and facilitate the production of antimicrobial peptides, a crucial part of our defense against illness (Bikle 7).

Moreover, Vitamin D has been linked to regulation of the activity of T cells, a type of white blood cell that plays a critical role in fighting off infections and tumors, as well as being involved in certain inflammation pathways in the body, and has been suggested to play a role in certain autoimmune and inflammatory diseases including: 

• multiple sclerosis
• rheumatoid arthritis
• psoriasis
• inflammatory bowel disease
• type 1 diabetes
• lupus
• prostatitis
• asthma
• thyroiditis (Bikle 45-48). 

Interestingly, the ability for Vitamin D to change the immune response may also be helpful to transplant patients by reducing the risk for transplant rejection (Bikle 48-49).

By stimulating these essential players in our immune response, sunlight exposure can help support our overall immunity and keep us healthy.

How Sunlight Synchronizes Our Sleep-Wake Cycle and Enhances Circadian Rhythms

Exposure to natural sunlight helps synchronize our body’s internal clock, known as the circadian rhythm, which controls our sleep-wake cycle and energy patterns. When we soak up sunlight in the morning, it signals to our bodies that it’s time to wake up and start the day, leading to increased alertness and energy levels. On the other hand, exposure to daylight in the evening can help our bodies wind down and prepare for sleep through the stimulation of melatonin production (An et al 4).

Our bodies are naturally designed to follow this pattern of light and dark, but our modern lifestyles often disrupt this balance. Prolonged periods of artificial light exposure from electronic devices can throw off our circadian rhythms, leading to irregular sleep patterns and decreased energy levels. That’s why incorporating some natural sunlight exposure into our daily routines can help regulate our sleep cycles and boost our energy throughout the day (An et al 4).

The Essential Connection Between Sunlight, Vitamin D, and Bone Health

We all know that calcium and vitamin D are vital for building strong bones. But did you know that sunlight exposure is a crucial component of the equation? Vitamin D synthesized from sunlight helps our bodies absorb and utilize calcium, promoting healthy bones and preventing conditions like osteoporosis, and calcium and Vitamin D supplementation in post-menopausal women reduces the risk for total bone fractures by 15% and hip fractures in particular by 30% (Siregar et al).

As we age, our bodies’ ability to produce vitamin D decreases, making it even more critical to prioritize sunlight exposure to support our bone health. So, next time you’re basking in the sun, remember that it’s not just giving you a nice tan, but also helping keep your bones strong and healthy. 

Other Lesser-Known Benefits of Sunlight

Aside from its well-known roles in energy levels, immune function, sleep patterns, and bone health, sunlight exposure has also been linked to other lesser-known benefits.

There is evidence that low Vitamin D levels are linked to conditions like:

• high blood pressure
• heart disease
• stroke
• obesity
• multiple sclerosis
• certain types of cancer 

More interesting is that these diseases have shown no positive impact from taking a Vitamin D supplement by mouth (Weller 3), underpinning the importance of boosting your vitamin D through sun exposure.  Increased Vitamin D levels have also been shown to reduce the risk of death for people with active cancer, as well as preventing the jump to type 2 diabetes for those with pre-diabetes (Bikle 37, Weller 3), while Vitamin D deficiency has been linked to an increased risk for type 2 diabetes (Bikle 37).

That said, much of the benefit of sun exposure for the human body does not result from Vitamin D at all. In fact, it has been shown that UV exposure, independent of Vitamin D entirely, can lower blood pressure and reduce heart risk – and the increase in blood pressure in winter months (as a result of lower UV exposure) results in a 23% increased risk for heart attacks or other cardiovascular events (Weller 3-4).

Similarly, it has been suggested in some studies that reductions in UV exposure led to worsening of outcomes for people with:

• multiple sclerosis
• ischemic heart disease
• COVID-19 infection
• and type 2 diabetes

These worsened outcomes remained unaffected by Vitamin D supplementation (Weller 5). Again, this exposes the importance of natural production of Vitamin D through sun exposure as a way to maintain the beneficial effects of the vitamin.

What about over-exposure to sunlight? Isn’t that bad?

While it is true that there are certain risks associated with increased exposure to sunlight, I would highlight again that there is no strong scientific evidence to suggest that too much sunlight increases all-cause mortality – to say it simply, too much sun will not reduce your lifespan, and can, as we just discussed, actually help many of us live a longer, healthier life.

So, what are these harmful effects of sunlight? Too much sun can lead to:

• sunburns
• premature aging of the skin
• increased risk of skin cancer, including melanoma (“Overview of Effects of Sunlight”; Weller 2).  

The fact that over-exposure to sunlight can have harmful effects emphasizes an important note: with the sun, as with most things in life, moderation is key!

To put it shortly, sunlight is not all sunshine and rainbows – but, if we consider that it contributes to reduced all-cause mortality, it’s more good than bad, contrary to the popular belief that has been erroneously hammered into our heads over the past several decades.

How Much Sunlight Should I Get?

The World Health Organization (WHO) recommends that adults get between 5 and 15 minutes of sunlight per day only 2 to 3 days per week, stating that this is enough to stimulate Vitamin D production while avoiding excessive UV exposure and an increased risk for certain conditions, like skin cancer (“Radiation: The Known Health Effects”). They don’t cite any specific scientific reference for how or why they reached the conclusion of this recommendation, but I was able to find one article, which cites several German studies, mentioning a variance of skin types which tolerate a different range of UV exposure prior to suffering a sunburn – the extreme ranges being up to 10 minutes for fair-skinned individuals and greater than 60 minutes for dark brown or black skinned individuals (“In Brief”). Perhaps these are the same studies from which the WHO draws its inspiration.

That said, the WHO seems to be missing an important point, which I have outlined above: that some of the arguably more helpful benefits of sun exposure are not related to Vitamin D at all (such as UV exposure lowering blood pressure and reducing risk for cardiovascular events).

Meanwhile, there was a recent study published which draws attention to what I personally believe to be the most important piece of information: the link between sunlight exposure and reduced all-cause mortality. In this study, published in Nutrition, Metabolism, and Cardiovascular Diseases early in 2024, it was found that participating in gardening, an activity which lends itself to regular sun exposure, resulted in a reduced total risk for death as well as decreased risk for cancer and heart related deaths – and this happened on a sliding scale, which means that more time spent gardening resulted in a greater reduction of said risk (Liang et al).

So, the real answer to the question of “how much sunlight should I get?” may actually depend. If you’re a pragmatist who draws a reasonable parallel between gardening and sun exposure, while leaning on the other evidence cited earlier in this article, then the answer is just: yes. If you’re the skeptical scientist type who is thinking, “Correlation is not causation!” precisely at this moment, and you can’t give a helpful or useable recommendation for fear of being proven wrong later, then the answer is a classic: it bears further study. If you’re a bureaucrat, unconcerned with practicality: You skimmed the first line of this section, saw the WHO recommendation, stopped reading, and then told that recommendation to everyone around you without any further thought to the question. Can you guess which of these I am?

To deepen the intrigue, I think we also need to consider the impact of dietary components on the risk for skin injury through UV exposure. Research indicates that consuming Omega-6 fatty acids, found in seed oils, elevates the risk of skin cancer while, conversely, eliminating seed oils from your diet can markedly decrease the likelihood of developing sunburn from UV exposure (Mercola and D’Adamo 12). So, how much of the harmful effects of sun exposure are less related to the sun and more related to the stuff we have been trained to put into our bodies by food manufacturers and governmental dietary guidelines for decades, at the detriment of our own health? Maybe that’s a topic to explore deeper later!

Am I recommending that you start spending every waking hour outside in the sun with zero protection? Of course not! However, I don’t believe you should overthink it. If you’re a reasonable adult (and if you’re reading this, you probably are) with any life experience, then you know what it looks like for you when you’ve spent too much time outside, and I would reckon you can exercise some common sense around how to avoid that. I’m reminded of the time I spent hours at the lake swimming hole with absolutely no sun protection when I was in middle school. My shoulders looked like Marvel’s “The Thing”, covered in what seemed like thousands of tiny, painful, fluid filled blisters – until a family friend unknowingly clapped his hands on my shoulders and squeezed as hard as he could in greeting, causing them to…  slough off… in an excruciating manner. Ouch!

Practical Tips for Harnessing Sunlight’s Wellness Boosting Power

Now that we have a better understanding of the science behind sunlight’s health and wellness effects, let’s explore some practical ways that I think you can incorporate more sunlight into your daily routine:

1. Rise and Shine: Start your day off on the right foot by opening your curtains or blinds and allowing natural sunlight to flood your space. Even a few minutes of exposure can help kickstart your body’s wake-up process and set a positive tone for the day ahead.
2. Morning Movement: Take advantage of the early hours to get moving outdoors. Whether it’s going for a brisk walk, practicing Pilates in the park, or simply enjoying your morning coffee on the patio, spending time outdoors exposes you to sunlight while invigorating your body and mind.
3. Outdoor Breaks: When the midday slump hits, resist the urge to reach for another cup of coffee and instead step outside for a brief sun break. All it takes is a few minutes of sunlight exposure to help boost your energy levels and improve mental clarity.
4. Al Fresco Dining: “Al Fresco” is an Italian term that means “in the fresh air” and is just a way of saying “outdoor” (I’m using it to sound fancy). Whenever possible, opt for outdoor dining to maximize your sunlight exposure during meals. Whether it’s breakfast on the balcony or lunch in the backyard, enjoying your meals outdoors allows you to soak up the sun’s energizing rays while nourishing your body with wholesome foods. Plus, who doesn’t love a good picnic?
5. Nature Time: Make it a point to spend time in nature whenever possible. Whether it’s hiking through your local park, taking a walk on the beach, or even just sitting beneath a tree in your backyard, being in nature exposes you to sunlight while providing numerous other health benefits such as reduced stress and improved mood.
6. Screen-Free Sunsets: As the day comes to a close, put away your screens and step outside to watch the sunset. Not only is this a peaceful and calming way to end your day, but it also allows you to soak up some last-minute sunlight before night falls.

Remember, these are just suggestions – ultimately, the best amount of sunlight for you will depend on your own personal circumstances and preferences. The most important thing is to find a balance that works for you and makes you feel good both physically and mentally.

In Conclusion

In wrapping up our discussion on the nuanced relationship between sunlight and health, it’s clear that the sun, much like anything else in life, offers both risks and rewards. While the overarching narrative has long focused on the dangers of overexposure, it’s essential to remember the myriad of benefits that sun exposure brings to our physical and mental well-being. From the potential for reducing all-cause mortality to the joy of a sunlit morning, the balance lies in thoughtful, moderate engagement with our closest star. The takeaway? Equip yourself with knowledge, listen to your body, and enjoy the sunlight in a way that feels right to you. After all, it’s about finding harmony in our lives and fostering well-being through a connection with the natural world. As you ponder your next steps in cultivating a healthy relationship with sunlight, remember that sometimes, the best path forward is the one lit by the gentle, warming rays of the sun.

Here’s to soaking up the sunshine for a happier, healthier life! 

P.S. Want to discover a new path to health and wellness that is repeatable, sustainable, and actually works? Start here!

Works Cited:

1. An, Mihyang, et al. “Why We Need More Nature at Work: Effects of Natural Elements and Sunlight on Employee Mental Health and Work Attitudes.” PLOS ONE, Public Library of Science, 23 May 2016, journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0155614&mod=article_inline.
2. Bikle, Daniel D. “Vitamin D: Production, Metabolism and Mechanisms of Action.” Endotext [Internet]., U.S. National Library of Medicine, 31 Dec. 2021, www.ncbi.nlm.nih.gov/books/NBK278935/.
3. “In Brief: How Much Sun Is Too Much?” InformedHealth.Org [Internet]., U.S. National Library of Medicine, 4 July 2022, www.ncbi.nlm.nih.gov/books/NBK321117/#:~:text=The%20skin%20of%20people%20who%20are%20sensitive%20to,becoming%20harmful%20after%20about%205%20to%2010%20minutes.
4. Liang JH;Liu ML;Huang SY;Huang S;Pu YQ;Jiang N;Bao WW;Zhang YS;Gui ZH;Hu LX;Pu XY;Li J;Chen YJ; “Outdoor Gardening Activity with Different Frequency and Duration May Be Associated with Reduction of Total and Cause-Specific Mortality Risk for General U.S. Adults: Findings from the Nhanes.” Nutrition, Metabolism, and Cardiovascular Diseases : NMCD, U.S. National Library of Medicine, 26 Feb. 2024, pubmed.ncbi.nlm.nih.gov/38658226/.
5. Mercola, Joseph, and Christopher R D’Adamo. “Linoleic Acid: A Narrative Review of the Effects of Increased Intake in the Standard American Diet and Associations with Chronic Disease.” Nutrients, U.S. National Library of Medicine, 13 July 2023, www.ncbi.nlm.nih.gov/pmc/articles/PMC10386285/.
6. “Overview of Effects of Sunlight – Dermatologic Disorders.” MSD Manual Professional Edition, Oct. 2023, www.msdmanuals.com/en-in/professional/dermatologic-disorders/reactions-to-sunlight/overview-of-effects-of-sunlight.
7. “Radiation: The Known Health Effects of Ultraviolet Radiation.” World Health Organization, World Health Organization, 16 Oct. 2017, www.who.int/news-room/questions-and-answers/item/radiation-the-known-health-effects-of-ultraviolet-radiation.
8. Siregar, M. Fidel G., et al. “Correlation between Serum Vitamin D Levels and Bone Mass Density Evaluated by Radiofrequency Echographic Multi-Spectrometry Technology (REMS) in Menopausal Women.” Narra J, 30 Apr. 2024, narraj.org/main/article/view/452.
9. Weller, RB. “Sunlight: Time for a Rethink?” The Journal of Investigative Dermatology, U.S. National Library of Medicine, 24 Apr. 2024, pubmed.ncbi.nlm.nih.gov/38661623/.