Play Video

The Sun Sessions: Vitamin D

Jason Boyd here from Bio+Logical Health and Nutrition bringing you session three of the Sun Sessions. No talk on sunlight would be complete without discussing vitamin D – the sunshine vitamin.

Now, as important as this nutrient is, for some reason a very large portion of the population shows a deficiency when testing, even despite supplementing it orally – sometimes in massive doses that seems to be hit or miss – and people are puzzled as to why oral supplementation isn’t working for them. So today I’d like to discuss a few reasons why that may be so and how we can optimize our D levels.

Sources of Vitamin D

There are three ways we get vitamin D: 90% comes from sunshine hitting our skin and 10% comes from food – like butter, seafood, pastured eggs, and organ meats. It’s important to point out that we’re talking about D3 – which is only found in animal sources. Plants – mostly mushrooms – contain D2, which is quite a bit different and about half as potent as D3. Now obviously, if either the sun or food sources weren’t available, then supplementation would be the third way to raise your levels – however, I don’t recommend supplementing unless you first have everything covered that I’m going to talk about today.

Real quick, I want to dispel a popular myth. Without going too deep into the science, whenever radiation from the sun with a wavelength of 290-315 nm – which is the UVB range – hits our skin, it penetrates it and is absorbed into the living cells of our epidermis by 7-dehydrocholesterol, which is then photoconverted into previtamin D3, and then turned into vitamin D3 inside the plasma membrane. From there it leaves the plasma membrane and diffuses into the capillary bed in the skin where it’s bound to the vitamin D binding protein to be shuttled off to the liver. And because this happens inside the cells of our skin and not necessarily on the surface – the whole notion of washing off vitamin D3 when you shower after sunbathing just isn’t true.


Only about 1% of solar UVB even reaches the surface of the earth – the rest is absorbed by the ozone layer. The amount of UVB that’s able to penetrate through the atmosphere depends on the angle of the sun at different times of the year, meaning vitamin D production depends on your time of day, your latitude and even altitude, because the higher you are, the less distance UVB has to travel. Clouds, glass, air pollution, smog, clothing, and sunblock all block UVB radiation, So if you’re using a sunblock with a high SPF that blocks 95% of the UVB, you’re also reducing 95% of the vitamin D you make. This is bad news because there’s a correlation between increased skin cancer, lowered vitamin D levels, and increased UVA exposure…which is exactly what sunblock does. It blocks UVB so you don’t burn, which lowers vitamin D production and allows more UVA to hit your skin. And because it’s blocking the UVB from burning you, you end up staying out in the sun even longer, exposing your skin to even more UVA, causing even more damage. If you need to block the sun, my vote is to either cover up or go under cover in the shade. You can also eat your sunscreen – colorful berries, watermelon, dark leafy greens, wild salmon, tomatoes – all those colorful pigments are called carotenoids and they help protect your skin from the inside out.

Now because human life started at the equator, where the sun is the strongest and most constant, we had to have efficient protection against a wide range of solar radiation. This protection is melanin – the pigment which gives us our skin color. So darker skinned people are more protected from burning, but they also don’t make as much vitamin D – which, I don’t believe is necessarily a bad thing – meaning, perhaps darker skinned people shouldn’t be trying to achieve the same levels of D as lighter skinned people because from a genetic standpoint, they’ve adapted to not need as much. Consequently, as we migrated farther north and south away from the equator, the angle of inclination of the sun would be increased, thereby preventing less UVB from reaching us, and thus, less vitamin D would be made. So we started evolving lighter skin color the farther we moved away from the equator, and perhaps we’re meant to have differing levels of D according to our ancestral zip code. So this means that it would be a good idea to do genetic testing to get a better understanding of your own ideal vitamin D levels and safe-sun exposure times.

As humans and other organisms were evolving and becoming dependent on the sun for photosynthesis and all these other biological processes, there needed to be a mechanism involved to help protect DNA and RNA and other proteins and amino acids from damaging UV radiation wavelengths outside of UVBs range. So the body only uptakes about 15% of the vitamin D being made from the sun. The excess vitamin D is quickly degraded by UVB light into different types of sterols that are protective and are then able to overlap those absorption spectrums outside of UVBs range, and so in this way that’s one of the things it’s thought that vitamin D and its photoproducts do – they act like a sunscreen and protect against UV damage because it absorbs UV radiation and dissipates its energy by rearranging the conjugated double bonds in these proteins. This photodegradation also helps to prevent vitamin D toxicity from overexposure to the sun, which protects our calcium metabolism. And so this is another big benefit of sun exposure and getting your D from the sun – the creation of these other photoproducts – the different sterols that have anti-tumor effects, and protect against cancer, skin cancer,  and other skin damage. So anything that blocks the sun from hitting our skin – that’s the first thing that can lead to a deficiency in vitamin D.

Another big issue that can lead to low D are chronic infections. Every single gut I test has at least one kind of infection going on – but usually multiple. Pathogens don’t want to be caught and killed, so one of the things they’ll do is interfere with your vitamin D receptors as a means to suppress your immune system so it can stay alive. The body activates a vitamin D metabolite called calcitriol to try and activate the vitamin D receptors. So when the infections interfere with the VDRs, the need for calcitriol goes up to activate them, and more vitamin D is pulled from its stores to make more calcitriol, thus driving down your D. So again, orally supplementing with D to correct a deficiency could end up feeding the infections. So it would make sense to first test the gut for infectious pathogens, and work on those guys to see if D levels come up.

Calcium and EMFs

Finally, blood calcium levels are the predominant negative feedback control for the amount of vitamin D we make. Oral vitamin D isn’t sulfated and although research isn’t 100% on this, it’s widely thought that it can’t be converted to the sulfated form, which is what we make from the sun. It may be possible for the body to sulfate oral D, but more research is needed. It would be good to know, however, as the sulfated form of D from the sun prevents it from affecting calcium balance – which is a good thing. This is important because we’re constantly exposed to EMFs from our electrical and wireless devices, which can cause calcium to efflux out of the cell and into the blood. Because of the negative feedback control, this could lead to the lowering of D as a protective measure. So if you supplement with D, it may raise your blood calcium to dangerous levels, causing a thickening of the blood called hypercalcemia, which is hard on the kidneys and heart.

Not only that, but vitamin D is meant to be in balance with your omega 3 and omega 6 fatty acids – sometimes called vitamin F. Now about 99% of the calcium in your body is found in your bones and teeth. The rest is in your blood and tissues. The movement of calcium between the blood and tissues is dependent on two things: Vitamin D and vitamin F. Vitamin D pulls calcium out of the tissues and into the blood. Vitamin F pulls it out of the blood and into the tissues. So if you’re artificially raising your D levels, not only may you be skirting dangerously close to hypercalcemia, you’re also reducing the amount of calcium in your tissues, like in your brain and nerves, which can lead to things like anxiety and depression – or like in your muscles, where it can also lead to pain and fatigue and other muscular disorders, because calcium is needed for muscular contractions. Calcium in the tissues helps regulate the immune response as well, so guess what happens when you mess with the balance of D and F? You start to have poor immune function.

So what all this means is that perhaps your body is lowering your D on purpose as a response to calcium efflux to protect you from a poor environment filled with too many non-native EMFs!

Low D could also be a genetic issue, in which case you may have no choice but to supplement it. So if you still have problems raising your D after correcting all these things we discussed today, then you may want to look into genetic testing. Likewise, testing your genetics can be helpful as I said before, for figuring out how long you’re able to safely stay out in the sun based on where your ancestral zip code was.

So these are just a few examples of why your vitamin D levels can be low and why I don’t recommend supplementing with it just to satisfy numbers on a paper. Low vitamin D is definitely a problem, but I suspect it’s more a symptom of other things, and you should probably address those first before just blindly supplementing it. Now in the event that you do decide to supplement with D, I strongly recommend supplementing with vitamin A and K2 to avoid calcification of soft tissue. I also recommend supplementing with magnesium, because vitamin D can’t be activated and utilized without sufficient magnesium. This may actually help explain D deficiencies or why many people need high doses of vitamin D to optimize their levels — it could be that they simply don’t have sufficient amounts of magnesium in their system to activate the vitamin D. And of course, don’t forget your omega 3s and 6s to keep blood and tissue calcium levels balanced.

So to wrap up…the human organism evolved under the sun. It isn’t trying to kill us. For billions of years, it’s been shining on the earth, giving life to everything it touches. Start aligning yourself to the wisdom of nature and understand that you need to strive for balance. Give your body what it needs, and then get out of the way and let it do its magic. You may be surprised at what happens.

If you missed the first two parts of The Sun Sessions, here they are:



Recent Videos

Beyond a Healthy Gut: Live Q&A w/ Steven Wright

Webinar – Live Q&A: Microbiome & Beyond w/ Kiran Krishnan

Webinar – Live Q&A: Understanding Hormones & Hormone Testing

Webinar – Introducing EndoAxis: A Revolution in Testing & Balancing Hormones (Naturally!)

Webinar – Deep Dive: Understand Your Hormones & Most Effective Hormone Testing w/ Dr. Liz Bartman Part 4

Jason Boyd

About our Guest

My name is Jason Boyd and I’ve spent over two decades nourishing and nurturing people from all over the world, in all stages of life, with all kinds of health issues.

My job is to assess where you’ve been, where you are now, and where you want to be, and then teach you how to provide yourself with the proper conditions you need to heal and be healthy. I help you coach up your adaptive physiology, engage your self-healing mechanisms, and restore balance and function back to your body by living in accordance with the laws of nature so that your evolutionary biology can thrive in our fast-paced modern world.

I created Bio+Logical Health & Nutrition out of a profound desire to help people live their best life. I’m not interested in diagnosing you or treating you for specific diseases, nor am I merely going to help you manage your symptoms.

My goal is to empower you with the knowledge you need to make the right decisions so you can enjoy the life you love with the people you love..

You’re not the disease you’ve been labeled with. You’re not the victim of bad genes.

You’re the creator of your best life.

It’s time you start living it.

Why Subscribe?

  • Save $$$ on your favorite products every time!
  • Refills arrive at your door, on time, every month.
  • Update/change subscriptions any time,
  • FREE SHIPPING in the US on order more than $75.
  • Check something off your "to-do" list forever!