By Perry Holman, Executive Director, Vitamin D Society

How did we get to this point in our relationship with the sun? If you follow the current health recommendations from some dermatologists you would live in perpetual darkness, in a bunker, and never let the sunshine hit your unprotected skin. Sunscreen use is advised to be applied to your skin everyday of the year regardless of the whether you are indoors or not. Regardless of your skin type. This action has unforeseen consequences that I hope to shine a light on for you.

For November, Vitamin D Awareness Month, we are focusing on educating people to the many benefits of sun and UV exposure. This is why we have named it UV→D NOW. Because getting UV exposure is important for vitamin D, nitric oxide and so many other photoproducts for your health. The lack of sun exposure is the main root cause of vitamin D deficiency, and studies have found that people with low vitamin D are at a higher risk of many serious diseases such as cardiovascular disease, major cancers such as breast and colorectal, autoimmune diseases such as diabetes and multiple sclerosis and even infections, flus, colds and much more.

Ensuring our immune system is functioning properly is so important today as we deal with COVID-19. Many research studies have found that vitamin D deficient people have a higher risk of severe COVID-19 including longer hospitalization and higher mortality. A recent study reported: "The findings of this study suggest that low UV exposure can affect the required production of vitamin D in the body, which substantially influences the dynamics of COVID-19 transmission and severity."1

Making sure you have adequate vitamin D intake through sun exposure is something we all can do to help boost our immunity and protect our personal health.

But let’s start back in the beginning. The sun has provided mankind with warmth and good health since the dawn of time. Your body cleverly developed a system to produce vitamin D naturally by having the UVB rays in sunshine penetrate your skin and react with the cholesterol to produce vitamin D.  In addition, sun exposure also produces other photoproducts and processes that contribute in many ways to have a positive impact on your health. These are not found in vitamin D supplements.

For example:

• Nitric Oxide is produced in the skin with UVA exposure. Nitric Oxide (NO) through vasodilatation and lowering of blood pressure reduces Cardiovascular Disease
• Serotonin is a neurotransmitter involved not only in mood, but also in cognition, regulation of feeding behavior, anxiety, aggression, pain, sexual activity, and sleep
• Endorphins released into the blood during UV exposure, may reach the brain in sufficient concentrations to induce mood enhancement and relaxation, reduce depression and provide pain relief
• Melatonin has a potent anti-oxidant effect
• UV light treats and helps prevent skin diseases such as psoriasis, eczema, vitiligo, acne
• UV light regulates circadian rhythm – circadian clock, which effects mood, sleep, and cognition

Your body was developed to be out in the sunshine not indoors. It needs and craves sunshine and UV exposure. Our body received all of this when we lived in the equatorial regions of the world and we were outside all day but this has changed. Research studies have found that people living these traditional lifestyles in Africa have a natural vitamin D level of 115 nmol/L².

Modern humans have moved. We migrated and now inhabit parts of the northern and southern hemisphere that only receive adequate sun exposure in part of the year. In the winter season the sun’s rays are on an angle and are too weak, below a UV Index of 3, to produce vitamin D in our skin. In addition, we mainly work and reside indoors. Even in the warmer months. We just don’t get the sun exposure our bodies need and were designed for, and this leads to vitamin D deficiency increasing our risk to a number of health consequences.

The solution? You need moderate, regular, nonburning sun exposure. This is what your body was designed for. This is also why your body develops a tan. A tan is a natural reaction from your body to increased UV exposure. Your body doesn’t want your skin to burn. So, it produces melanin which gives your skin a darker tone to help protect you from burning.

Some people have very fair skin that evolved for more efficient vitamin D production in very limited UV conditions such as those found at very high latitudes. Their skin unfortunately does not turn dark or tan from UV exposure. The melanin produced in their skin is more reddish in colour and does not protect from burning like the darker brown melanin. These people are classified as Fitzpatrick Skin type I and should limit their exposure to sunshine and UV. They typically have red or blond hair with blue or green eyes and burn easily from sun exposure.

For people who are Fitzpatrick Skin type II and higher, who can produce a tan, you should start off in the spring with a limited amount of sunlight exposure until your skin acclimatizes and develops a tan. Once this happens you will be able to gradually spend a longer amount of time in the sun and receive all the benefits outlined above. You still must know your skin and its condition and make sure that you do not burn.

To find out your Fitzpatrick Skin Type take the survey here.

Winter still poses a problem for us. At our Canadian latitude how do we get the continued benefits of sunshine and UV exposure? You can travel south if that’s an option for you. You would have to go below the 35^th parallel which is about Atlanta, GA, for the sun to be strong enough (UV Index >3) to produce vitamin D in your skin.

If you’re stuck like me here in Canada there are artificial UVB alternatives to consider. For example, a recent research report³ found that a sunbed with similar UV lamps as summer sunshine (95% UVA, 5% UVB) can provide the same benefits of summer sun exposure and raise your vitamin D level to optimal levels. A professional salon offering sunbed services may be able to help you if you are Fitzpatrick skin type II or above through the winter until spring arrives. You don’t need to get a tan, to make vitamin D or nitric oxide.

But most importantly, don’t let your vitamin D levels drop to deficient levels through winter. If you are unable to go south and do not want to use artificial UVB sources, please consider taking a vitamin D supplement to prevent vitamin D deficiency. Remember this is not a replacement for everything you get from the sun. Adults will need about 4,000 IU/day to replace what their body uses.

The only way to know for sure if you are deficient or not is to test your vitamin D level or 25(OH)D. You can request this through your family doctor or you can consider using a service like GrassrootsHealth who offer vitamin D home test kits.

Make sure you get your test score and compare it to the level recommended by a group of 48 vitamin D scientists who recommend in their Scientists’ Call to D*action, that everyone, all ages, achieve a vitamin D level of between 100-150 nmol/L (Canada) or 40-60 ng/ml (USA) for optimal overall health.

Even having the sun shine through my window and brighten my office makes me feel better, happier and more motivated. It’s a wonderful thing. And sun exposure has many more benefits than just found from vitamin D. But remember you can’t make vitamin D sitting in your office. Get outside! I hope you let the sun back into your life!

References:

1. Mukherjee SB, Gorohovski A, Merzon E, Levy E, Mukherjee S, Frenkel-Morgenstern M. Seasonal UV exposure and vitamin D: Association with the dynamics of COVID-19 transmission in Europe. FEBS Open Bio. 2021 Oct 5. doi: 10.1002/2211-5463.13309. PMID: 34608759. https://pubmed.ncbi.nlm.nih.gov/34608759/

2. Luxwolda MF, Kuipers RS, Kema IP, Dijck-Brouwer DAJ, Muskiet FAJ. Traditionally living populations in East Africa have a mean serum 25-hydroxyvitamin D concentration of 115 nmol/L. Br J Nutr. 2012 Nov 14;108(9):1557-61. doi: 10.1017/S0007114511007161. Epub 2012 Jan 23. PMID: 22264449. https://pubmed.ncbi.nlm.nih.gov/22264449/

3. Kimball SM, Lee J, Vieth R. Sunbeds with UVB radiation can produce physiological levels of serum 25-Hydroxyvitamin D in healthy volunteers. Dermatoendocrinol. 2017 Oct 17;9(1):e1375635. doi: 10.1080/19381980.2017.1375635. PMID: 29484099; PMCID: PMC5821157. https://pubmed.ncbi.nlm.nih.gov/29484099/