When it comes to the sun and sun protection, it seems there are more or less two camps.  There are those that no matter the season, religiously apply an SPF year-round.  According to this group, if the sun is up then so are it’s harmful assortment of rays. A good sunscreen is therefore all important and will ensure that we are protected from that accidental exposure (think the walk from the car to the office) that can take a cumulative toll on the dermis. Then there are those on the opposite spectrum that argue that unless you are living two degrees or so from the equator, a daily sunscreen is overkill. If you spend most of your time working indoors and reside in the Northern Hemisphere then you are more or less safe from the sun’s rays. Unless we are outside for an extended period of time, a slathering of an opaque white film on exposed skin seems quite alarmist.

Our relationship with the sun seems a love/hate one that is difficult to reconcile. We love it for the benefits that it confers- foremost the health promoting production of vitamin D, that essential hormone that switches on our immune system and elevates our mood. Add to this the glow that we get after a little sun exposure (glutathione production, check) it seems in one sense indisputable that if we are built to make vitamin D with our skin then that is part of our very design and proof that we are meant to go in the sun- at least a little- and that is what we should do.

And yet many of us are wary of it and rightly so.  These days it seems the sun’s rays are stronger than ever and clocking in too many hours not only gives us an unhealthy dose of radiation but is ultra damaging to our precious outer layer of skin in ways that is difficult to reverse.  Yes, we have all partaken in the folly of spending that extra 20 minutes when we could feel the time to seek shade was long overdue. Or the time when on an island holiday we thought that a thin layer of white summery fabric would be a sufficient barrier between ourselves and the sun gods. Or how about when you went swimming and mistakenly thought '.... it's a cloudy day so I should be ok..."?   

Perhaps it is wise to be somewhere in the middle: open to being a recipient of the sun’s happy and healthy vibes but knowing that there are common sense guidelines we should observe while doing it. Just as it is not in best our interest to fear the sun is also unadvisable to recklessly overdo it. There is a way to sun and a way not to sun and how to best protect yourself and in the case where we have overdone it, taking specific steps to reverse the damage.

Ray of light

If there isn’t yet a consensus about the need to go in the sun there seems to be some sort of agreement on the simple fact that Vitamin D is good for us and we need more of it. The benefits are without question with some even arguing that it may be one of the simplest solutions to a wide range of chronic health problems plaguing the west. Of the 30,000 or so genes in the human body, Vitamin D is estimated to affect at least 3,000 of them. Auto-immune disease nagging at you? Vitamin D. Susceptible to the flu or infections (read Covid)? Vitamin D. Want to maintain bone and muscle health? Vitamin D. Is your hair growth stubbornly anemic and your length stuck at the same place for months? Vitamin D.  Some even claim that those that get regular doses of sunshine have better collagen and thicker skin compared to those who don’t.   While taking it in pill form is good and fine and absolutely necessary in the bleak winter months, the ideal is always to make it through direct contact with the skin. In pill form, hormone D is fat soluble and in many ways inferior to that version made naturally with sun and skin. When our skin comes into contact with the sun (sans sunscreen) the D we make is water soluble and stays in circulation two to three times longer than pill form.

But the benefits of regular sun exposure are not at all limited to Vitamin D.  When human skin is exposed to sunlight it produces several hormones and peptides that contribute to overall systemic health and wellness, which may be the reason why it just feels so good to be in the sun. Without getting too technical,  substances made from chemical reactions with sunlight are called photoproducts. While vitamin D is the most universally recognized health benefit humans receive from sun exposure, it is really just one of many important photoproducts. 

Some of the healthy photoproducts all made with the same ultraviolet B (UVB) wavelength range include: 

Vitamin D3- Widespread impact on hard and soft tissues in the body. Impacts musculoskeletal, cardiovascular, neurological, and immune system 

Calcitonin Gene Related Peptide (CGRP)- Reduces hypertension, reduces inflammation and regulates the immune system

Neuropeptide Substance P (SP)- Promotes proper blood flow and regulates immune system 

Adrenocorticotropic Hormone (ACTH)- Reduces inflammation and regulates immune system

Melanocyte Stimulating Hormone (MSH)- Reduces inflammation and increases libido

Calcitriol- Regulates cellular function and is involved in all major systems of the body 

Beta Endorphin (BE)- Increases relaxation, acts as a natural painkiller and promotes feeling of well-being 

Intelligent design 

How exactly is Vitamin D made?  Vitamin D production naturally occurs in the body when ultraviolet B (UVB) light hits the skin and converts a specialized cholesterol to pre-vitamin D3. Pre-vitamin D3 is then converted to vitamin D3 in the skin and transferred to the blood stream over the course of several days. After arriving in the liver, vitamin D requires two metabolic conversions to become calcitriol, the active form of vitamin D. Calcitriol binds to vitamin D receptors in almost every cell throughout the body. This process is regulated by the body and bioavailability is managed by several internal control mechanisms.  So when vitamin D levels are low the body will naturally know to boost levels and conversely when levels are high, it will reduce them to prevent toxicity.

What must be stressed here is that cholesterol does play a large role in Vitamin D production through the skin.  If you are lacking cholesterol it may be the case that you don't have the building blocks to make Vitamin D, even if you do go out in the sun.  Long demonized in the media as something to be avoided, reduced and controlled we now know that cholesterol is the healer in the body and we need more of it.  Think eggs, cheese, butter and organ meats such as liver.  

Peaky hours 

But when is the best time to catch some rays? The dominant narrative in the media used to be (and perhaps still is) that is not in our interest to venture out in the sun’s peak hours. While the summer sun is definitely strongest between the hours of 11 and 2 it is important to note that unless the sun is at the right angle relative to the horizon (above 50 degrees) then the possibility of producing vitamin D is very unlikely. The sun needs to be at a certain height in the sky in order for UVB rays to be present- those being the rays needed to make D. A late day or setting sun may still feel nice (due no doubt to healing infrared waves) but will also expose you to the harmful UVA rays which may still result in a tan but also radically increases your risk of skin cancer and unwanted photo-aging.  The solution:  go out into the sun at peak times and get your dose of D but do so mindfully:

• watch the time closely (10-15 minutes is all that is needed on exposed skin)
• avoid tanning the delicate skin on your face (think large hat or sunscreen)
• avoid sunscreen on areas that you are exposing to the sun to produce Vitamin D, as this will block production
• avoid washing exposed areas with soap for 24 hours as this can eliminate some of the vitamin D 
• go out gently at the beginning of the season in order to acclimatize your skin to the sun
• avoid ‘tanning’ through windows as this filters out most of the UVB while UVA rays are still present
• understand that through the months of September to March in the western hemisphere it is not possible to make Vitamin D, so supplementation with D3 (not D2) is essential