The ‘WHY’ and ‘WHAT’ of sun exposure and vibrant health
This time of year it is hard not to enjoy the extra light and warmth of the spring sun and given the general enthusiasm for the sun at this time of year I figure now is a good time to talk to the value of regular sun exposure for general health and vitality.
As a culture we are pretty comfortable that a bit of sunlight is a good thing but I’d like to take this further and say that the ‘little bit’ we are getting is usually not enough. That our increasingly indoor lives (dominated by artificial light) has contributed to a nationwide sunlight deficiency that is having serious health implications.
A culture of fear has built up around sun exposure and we are now avoiding, both deliberately but also structurally through the setup of our lives, something that is vital for robust health and critical for a holistic picture of health and vitality.
I’m writing this article because I have a passion for reframing our current relationship of fear with the sun, to one of value and deep respect. I strongly believe we are hurting ourselves with current mainstream approaches to the sun and would go so far as to say that regular and wide ranging sun exposure is the new superfood you aren’t having!
To me our ancient biology evolved in relationship to the sun and through years of research and body exploration I have come to believe that regular exposures to sunlight is actually a critical part of the healthy expression of our greatest biological potential. Basically our current sun avoidance policies are making us ill and blocking our health.
If you are already stirred with cries of “sun = cancer” then you should probably read on…
Sunlight and epigenetics: Turning on our vitality
Our skin has its own human form of ‘photosynthesis’. It convert sunlight into a healing and regenerative steroidal hormone precursor, called vitamin D. Vitamin D, which we obtain primarily through sun exposure, not via diet, is responsible for supporting over 2000 bodily functions to work optimally and in the form of vitamin D3 can activate over 300 genes.
Exposure to sunlight and the production of vitamin D is literally written into the healthy expression of our genes. For example one study conducted by Dr. Michael Holick’s Ph.D., M.D. (an American endocrinologist, specialising in the field of vitamin D) showed that healthy volunteers who increased their vitamin D by 2,000 IUs per day for a few months up-regulated 291 different genes that control up to 80 different metabolic processes (ranging from improving DNA repair, boosting immune system function, to improving autoxidation – which has implications for aging and cancer).
We have receptor sites for vitamin D (called Vitamin D Receptors or VDRs) on EVERY part of our skin and when these receptors are not filled with sunlight there is an increased chance that sticky bacterial adhesions (bad news) glue to and bind up these VDRs, switching them off, which then down regulates our immune function, causing inflammation as well as interfering with our healthy gene expression (potentially turning on a large number of disease causing genes).
Sun spectacular-ness (aka the benefits)
So what are the benefits of regular healthy doses of sunlight?
- Improved sleep quality and quantity: Too little light during the day and too much artificial light at night negatively impacts our melatonin production (the sleep well hormone) and therefore our ability to sleep well and rejuvenate at night.
- Improved daytime wakefulness: Sunlight signals your hypothalamus and all related organs and glands to be alert and produce optimum levels of your ‘wake up’ hormones (especially early morning sun).
- Improved immune function: Getting more sun increases the efficiency of your immune system (think flus, colds and infections of all kinds). This is a big one because not getting enough sun leaves you wide open to a bunch of viruses, fungi, bacterial infections as well as reduced ability to heal from injury and every day stresses.
- Prevention of autoimmune diseases: Vitamin D is a potent immune modulator, making it very important for the prevention of autoimmune diseases, like multiple sclerosis and inflammatory bowel disease.
- Improved cardiovascular health: Vitamin D is very important for reducing hypertension, atherosclerotic heart disease, heart attack, and stroke. Vitamin D deficiency increases the risk of heart attack by 50 percent according to one study (ref below). Further to this, the study found that if you have a heart attack – while being vitamin D deficient – your risk of dying from that heart attack is nearly 100 percent! VDRs amazingly are also present even in our cardiac muscle and respond positively to sunlight on the skin improving cardiac function. Cholesterol, sulfur and vitamin D from sun exposure all work together to protect your heart, brain, and blood vessels, so it’s important that you have sufficient amounts of all three.
- Emotional balance: The neurotransmitter serotonin (known as the happy feelings and well-being neurotransmitter) rises with exposure to bright light and falls with decreased sun exposure. Sunshine also causes a release of endorphins. There are also multiple studies that show a relationship with low vitamin D levels and depression.
- Healthy, vibrant skin: The skin’s cellular renewal process is dependent upon vitamin D. Broader than just vitamin D, sunlight itself can help with skin blemishes, acne, eczema, bacterial/fungal infection, even psoriasis and can actually reduce fine lines and wrinkles through reducing inflammation and improving skin function and resilience.
- Improved gut health: Our intestinal integrity has a strong relationship with the sun. Our skin and our guts have a complex intimate relationship and if one is down regulated it will usually show up in the other as well. Our access to vitamin D is integral to this relationship and the health of the mucosal barrier of our gastrointestinal wall. A vitamin D deficiency increases susceptibility to a number of conditions such as inflammatory bowel disease.
- Decreased likelihood of osteoporosis: It is well understood that vitamin D is a crucial component of healthy bones and teeth and the utilisation of minerals such as calcium for building and maintain strong bones.
- Improved thyroid function: Both cortisol and melatonin (which are supported by sunlight exposure) influence healthy thyroid hormone production. In addition a vitamin D deficiency is also associated with autoimmune thyroid disease.
- Cancer prevention: Yep, slathering ourselves in chemically laden, hormone disputing petro creams to protect against skin cancer might not be as straight forward as it seems. The Journal of the American Board of Family Health says “There currently is little evidence that sunscreens are protective against CMM {Cutaneous Malignant Melanoma}. A number of studies suggest that the use of sunscreen does not significantly decrease the risk of CMM, and may actually increase the risk of CMM and sunburns.” Cancer is increasingly being linked to sunburns, not sun exposure – an important distinction. There is also much research that points to the protective nature of healthy sun exposure to life threatening skin cancers!
- Longevity: Yep higher vitamin D levels are associated with longevity and low vitamin D level have been found to be significant indicator of mortality!
There is more but this article is already too long! The reality is that we are only just beginning to understand the full spectrum of nutrients we receive from the sun (it really goes beyond just vitamin D synthesizing), but there is more than enough evidence to get us thinking more about (and feeling into) how we would like to relate to the sun in the future.
In part two of this article we will explore the ‘How’. How much is enough? How do you go about doing it strategically (avoiding the burn)? And how to start.
Love and sunshine
Amber
Resources and references:
- Dr Michael F. Holick’s website and his awesome book The Vitamin D Solution.
- This interview with Nadine Artemis by Daniel Vitalis (Rewild Yourself Podcast) is a must listen for understanding the full value of regular sun exposure: Wise interaction with the Sun.
- Broader articles/videos on vitamin D and health outcomes (here, here, here, here and here).
- A great resource for the value of sunlight at the Sun, Nutrition and Health Research Centre
- Some condition specific studies, articles and books:
- Sunlight, sleep and wakefulness: Sleep Smart: 21 Essential Strategies To Sleep Your Way To A Better Body, Better Health and Bigger Success
- Vitamin D deficiency and thyroid dysfunction (here and here).
- Sunlight, vitamin D levels and cardiovascular health (here, here, here, here and here).
- Sunlight and gut health (here, here, here and here).
- Vitamin D and autoimmune disease (here).
- Mortality prediction and vitamin D levels (here, here, here and here).
- Vitamin D deficiency and depression (here and here).
- Sunlight and immune function (here and here).
- Sunscreen and cancer (here and here).
- Sunlight and skin cancer prevention (here).
