The 21st Century Guide To Vitamin D

Light On The Subject
Getting enough Vitamin D is nothing to bat an eyelash about; yet, despite being a key component of our overall well-being, Vitamin D can be deceptively tricky to get, especially in far-latitudes such as Alaska.  Regardless of where you are, whether North Pole, South Pole, or even Equator, this guide will arm you with the know-how to understand exactly what’s going on with Vitamin D and your body, why it’s so important, and how to make sure you’re getting enough.

You may have heard Vitamin D called the “sunshine vitamin,” nicknamed for its ability to instill a sunny mood and for our body’s dependence on the sun to produce it.  People first thought Vitamin D was mainly useful for building strong bones to ward off diseases like rickets, but new research shows the Vitamin D kicking around in your system is likely doing more than you realize, playing an important role in both your health and happiness (1).

Vitamin D receptors have been found all over the body even in the heart and reproductive organs (2,3).  That's right.  Even "where the sun don't shine" benefits from the sunshine vitamin.  In fact, “It’s estimated upwards of 2,000 genes are directly or indirectly regulated by Vitamin D” (4).  That's a lot of genes!  That's a lot of Vitamin D!  

Another way to wrap your head around the importance of getting enough Vitamin D is to look at the converse:  what happens when we don’t get enough.  Vitamin D deficiency is implicit in a host of diseases and symptoms including, but not limited to depression, breast cancer, multiple sclerosis, Alzheimer’s, and even plain old fatigue.

Clearly, from our body's standpoint, Vitamin D isn't just some optional additive we should toss in whenever we have the chance. It's an essential ingredient to our health, happiness, and overall well-being.

D-Talks

There are common misconceptions about Vitamin D, misconceptions worth detoxing from.  Even the term Vitamin D itself is a bit of a misnomer.  Despite the word “vitamin” appearing in the name, Vitamin D isn’t really a vitamin.  It’s actually a hormone (2).

You see vitamins are nutrients our bodies are unable to produce on their own, instead obtaining them from the food we eat.  Hormones, on the other hand, are body-process regulators that our bodies are able to self-produce (such as testosterone, estrogen, and adrenaline).  Vitamin D is much more akin to the latter.

Take for instance the fact Vitamin D, for the most part, doesn't naturally occur in food.  The list of foods naturally containing Vitamin D is shorter than the weekend: namely fatty fish, beef liver, egg yolk, and certain mushrooms.  Even human breast milk contains next to no Vitamin D (5).  Furthermore, in the few foods in which Vitamin D does occur, it’s in such minuscule amounts, it is effectively impossible to get enough.  For instance, to hit the Vitamin D Council’s daily recommendation, you’d have to eat well over 100 eggs every day (6).  That’s even more eggs than Paul Newman in Cool Hand Luke (in the movie, Newman ingests 50 eggs on a bet).

Newman's character ingesting 50 eggs in Cool Hand Luke.  This method is more likely to leave you with a stomach ache than adequate Vitamin D.

The moral of the story is unlike other “vitamins,” we simply can’t get adequate Vitamin D from the food we eat, but like hormones, our body can produce Vitamin D naturally.  It just needs a little help from the sun.

Bright Idea

The sun is a wonderful thing, enabling life on Earth to exist as we know it.  It comes in handy for a number of tasks we often take for granted such as setting our circadian rhythms so we wake up and wind down at the right time, generating serotonin in our brains so we feel good, and among other things, helping our bodies produce Vitamin D.

When it comes to producing Vitamin D, we are surprisingly plant-like.  In our skin, we have dormant Vitamin D precursors (actually a form of cholesterol).  Much the way a plant makes food from the sun, when UVB (Ultraviolet B) rays from the sun hit our skin, our body can then “photosynthesize” these Vitamin D precursors into bonafide, Vitamin D.  Without the sun, this can’t happen.

Not just any namby-pamby ray of sunlight will do, though.  To make Vitamin D, that ray of sunlight must, I repeat, must contain UVB rays, something our atmosphere can be pretty adept at filtering out.  This is where the height of the sun comes in.

Lighten Up

In order for UVB rays to make it through the atmosphere to our skin, the height of the sun (more formally referred to as the solar altitude, angle, or elevation) must be at least 20 degrees (7).  In other words, when the sun is 20 degrees or higher in the sky, our bodies can start making Vitamin D.  Higher is of course better, resulting in faster Vitamin D production, but a 20 degree solar elevation is the key metric where production starts/stops.

Now, the angle of the sun depends primarily on two factors: the time of day and the time of year.  During the beginning and end of the year (winter) the sun doesn’t get as high as it does during the middle of the year (summer).  Similarly, during the beginning and end of any given day (sunset, sunrise), the sun isn’t as high as it is during the middle (solar noon).  In summary, during the “middles” (both of the year and day) the sun is higher than during the “beginnings and ends.”

There’s an incredibly useful term for this middle of the day time called “solar noon,” astrology-speak for when the sun is at its highest each day.  On the equator, solar noon corresponds to time-of-day noon, but the further north or south you live, the more solar noon separates from time-of-day noon.  Currently in Anchorage, Alaska, post-daylight savings time, “solar noon” is actually about 2pm.

Being outside around solar noon is incredibly helpful for bolstering your Vitamin D production.  With the sun at its highest, this is when your body will have the best chance to produce the most Vitamin D in the shortest amount of time.

Okay, so you know the sun needs to be at least 20 degrees in the sky and better yet at solar noon, but where on Earth do you find this incredibly useful, life-changing information?

Well, you could use the length of your shadow and trigonometry like the ancients did…Or, you could head to this incredibly handy site:  

https://www.timeanddate.com/astronomy/usa/anchorage

This site will tell you everything you ever wanted to know about the sun’s positioning including how high it is. (Please note: solar altitude, elevation, and angle are all interchangeable terms for the same thing: how high the sun is in the sky.  This site likes to use the term “altitude.”)

Thanks to the magic of the internet, you too can divine the height of the sun at any given time.  Here, we have a solar altitude of 34 degrees, well above the necessary 20 degrees needed to make Vitamin D.  From: timeanddate.com

As a bonus, you can also use your shadow to approximate solar elevation (which, let's face it, is kind of cool).  This can come in handy if you're camping, in a pinch, or trying to impress prospective dates.  These shadow lengths correspond to the following solar elevations:

1. Shadow is circular blob at feet, solar angle is 90 degrees

2. Shadow is as long as you are tall, solar angle is 45 degrees

3. Shadow is 2.75 times as long as you are tall, solar angle is 20 degrees (the cusp of making Vitamin D)

Using your shadow (or your dog's) you can handily estimate the sun's height in the sky.  Useful for wooing dates and generating Vitamin D.

So, you’ve taken care of the atmosphere blocking UVB rays by getting outside when the sun’s at least 20 degrees high in the sky.  That’s step one.  But, there are other things that can still hamper UVB rays from hitting your skin and producing Vitamin D, the most fundamental offender being your clothes.

Clothes Call

If you think of your skin as a giant solar panel for generating Vitamin D, you’re on the right track.  Our skin is actually our body’s largest organ and when it comes to Vitamin D this is a boon.  The more skin exposed, the faster your body will produce Vitamin D.  Show as much skin as socially acceptable.  Take off your shirt.  Roll up your shorts.  Heck, if your location allows it, get naked.  This will allow your body to generate lots of Vitamin D in very little time.

Two exquisite(ly pale) human specimens demonstrating good Vitamin D etiquette.

Now, remember it’s the UVB rays your skin needs to synthesize Vitamin D.  So, anything that blocks UVB light effectively halts Vitamin D production.  While clothes and a low sun may be the most obvious offenders, there are a few less-obvious offenders you should know about: Glass-windows, cloud-cover, and sunscreen (8).

1. Glass windows.  The fact glass blocks Vitamin D synthesis goes a long way towards explain why so many people are deficient.  Even on a sunny day, unless that sun is streaming unobstructed (such as through an open window or screen), we aren’t making Vitamin D when indoors.

2. Cloud-cover.  Though an overcast day can block UVB light, it’s worth noting that a partly cloudy day can actually amplify it due to the scattered clouds acting like mirrors.  Similarly, snow on the ground or water can also reflect UVB rays, increasing Vitamin D production rather than hampering it.  In general, if the clouds prevent you from seeing your shadow, you can’t produce Vitamin D (9).

3. Sunscreen.  This is a big one.  If you’re wearing sunscreen you aren’t producing Vitamin D.  It’s also worth noting the shade of your skin also acts as a semi-natural sun block.  A darker skin type will block more UVB.  This doesn’t mean darker skin types can’t produce Vitamin D, just that they require more sun exposure to do so (8).

Now, at this point, you may be thinking:  But everyone’s told me to wear sunscreen my whole life!  There’s even a famous song about the virtues of wearing sunscreen!  Now you’re telling me NOT to wear sunscreen?  What kind of blasphemous skin-cancer promoting buffoon are you!

You would be right for having these concerns even if your rhetoric may have gotten a little carried away.  Thankfully, you don’t have to choose between a life of skin-cancer and Vitamin D deprivation.  According to the Vitamin D Council, you can generate ample Vitamin D in only half the amount of times it takes for your skin to turn pink (8).  The exact length of time this ends up being will depend on the solar elevation, but the key is you don’t get have to get a sunburn.  You don’t even have to turn pink!  However many minutes it would take your skin to turn pink, cut that in half and you’ve made ample Vitamin D.  After this, please, by all means, slap on some sunscreen!

Certain reflective surfaces like snow, water, and even partial cloud cover can actually enhance the UVB exposure needed for Vitamin D production.

Light Reading

So, the sun is at least 20 degrees in the sky.  You’re showing some skin, all while making sure not to accidentally block any UVB rays with glass or sunscreen.  Now, you may be thinking, geez that’s a lot of work!  Why would I go through all that when I could just take a supplement from the supermarket?  One of the main reasons is self-regulation. 

The cool thing about when your body generates Vitamin D from the sun is it automatically self-regulates.  Your body will produce only as much Vitamin D as you need and stop when you have enough, automatically optimizing your Vitamin D levels for you.  This is especially beneficial because it is possible to get both too little and too much Vitamin D, neither of which is good for you.

With supplements both of these outcomes are a possibility.  It can be easy to get inadequate amounts due to absorption problems (to facilitate absorption, it is recommended to always take Vitamin D supplements alongside a source of fat, since Vitamin D is fat-soluble substance, meaning it takes fat to dissolve).  It can be challenging to get enough if your body simply isn’t absorbing the supplement, and there’s no real way to know short of a blood test.

If you aren’t getting enough, you can increase your dosage to compensate, but it’s also possible to get too much Vitamin D and experience a condition called Vitamin D toxicity where soft tissues like blood vessels and organs begin to harden (14).  This is because supplements contain a form of already activated Vitamin D.  Once absorbed, your body has no choice but to use it, essentially being force-fed Vitamin D.

This isn’t to say supplements are bad (in fact, sometimes they are entirely necessary), only that dialing in the correct dosage of Vitamin D can be an experimental trial-and-error process: You try a certain dosage, check your Vitamin D levels with a blood test, readjust your dosage, and repeat until your levels are optimal.  To say the least, it can be a tedious process.

As you can see, one of the main benefits of getting Vitamin D from the sun (besides it being the way our bodies were designed to receive it) is you don’t have to worry about any of the above.  With adequate sun exposure, your body will self-regulate, automatically producing optimal levels of Vitamin D making sure you are neither deficient nor toxic (11).  All you have to do is enjoy the sun.

Pictured: An Alaskan sunbathing in their natural habitat

Northern Exposure

However, especially in Alaska and other far-latitudes, it isn’t always possible to get adequate levels of sun exposure.  Producing Vitamin D from the sun while preferred, sometimes simply isn’t an option.  In Anchorage, Alaska from October 15th to February 25 it is impossible to generate Vitamin D from the sun (12,13).  Between these dates, it is absolutely essential to use supplementation.

The Vitamin D Council recommends between 5,000 IU (International Units) and 10,000 IU a day (10).  Personally, when taking 5,000 IU during the winter I still came up deficient.  It was 10,000 IU this past winter that landed my levels at not only adequate, but optimal, weighing in around 50 ng/ml.  I would recommend (obligatory I am not a doctor statement) starting with 5,000 IU and then have your levels checked at a health fair or by a doctor mid-winter, bumping up to 10,000 IU if your levels are still lacking.  It’s important to note that previously, Vitamin D blood levels of 20 or 30 ng/ml were considered adequate, but this was based off old research primarily focused just on preventing rickets.  Current research shows optimal Vitamin D blood levels are closer to 50ng/ml (10).

In addition to the amount, the type of Vitamin D is also important.  The best kind of Vitamin D to supplement is Vitamin D3 since it is the same as the type of Vitamin D your body would naturally produce were it exposed to the sun.  Vitamin D2 is the inferior kind that the body seems to have more trouble utilizing due to it being more akin to a foreign substance.

Vitamin D3 comes from two primary sources: fish skin and oil from sheep wool.  The oil from sheep wool (lanolin) has a similar Vitamin D precursor to our own skin.  This precursor containing oil is wrung from the wool and then artificially exposed to UVB light in order to activate it.  The Vitamin D found in fish skin is already activated coming from the plankton they eat.  However, fish are at risk for mercury exposure and also contain ample amounts of Vitamin A, which can become toxic in high amounts. Because Vitamin D from sheep wool oil doesn't share these complications, most Vitamin D3 comes from sheep wool oil.  This is widely considered to be the best and safest kind (15).

Sunning It All Up

In summary, Vitamin D is a quintessential hormone integral to our health, happiness, and well-being.   Thanks to the body’s built-in self-regulation, Vitamin D produced by the sun is the most natural, quickest, and safest way to obtain and maintain optimal levels.  At least a 20 degree solar elevation plus some bare skin is all you need to start making Vitamin D.  For optimal Vitamin D production, aim to be outside around solar noon. 

While Vitamin D from the sun is the best, during certain times of the year, when the solar angle is less than 20 degrees, Vitamin D simply can’t be made from the sun.  During these times, supplementation becomes absolutely necessary, in which case 5,000 IU to 10,000 IU of Vitamin D3 taken alongside a source of fat often does the trick. 

So what are you waiting for?  Get out there and make some Vitamin D!  I hope this article has been enlightening.

This article was written in the sun whilst soaking up Vitamin D.

Sources:

1. http://www.webmd.com/diet/guide/vitamin-d-deficiency#1
2. http://www.lifeextension.com/magazine/2013/8/the-overlooked-importance-of-vitamin-d-receptors/page-01
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3695598/
4. https://www.sciencenews.org/article/vitamin-d-essential-modern-indoor-lifestyle
5. http://kellymom.com/nutrition/vitamins/vitamin-d-and-breastfeeding/
6. https://www.vitamindcouncil.org/about-vitamin-d/testing-for-vitamin-d/
7. https://www.vitamindwiki.com/Vitamin+D+vs+angle+of+the+sun
8. https://www.vitamindcouncil.org/about-vitamin-d/how-do-i-get-the-vitamin-d-my-body-needs/
9. https://fastrt.nilu.no/VitD_quartMED.html
10. https://www.vitamindcouncil.org/why-does-the-vitamin-d-council-recommend-5000-iuday/
11. http://www.foodmatters.com/article/vitamin-d-myths-and-facts
12. https://www.timeanddate.com/sun/usa/anchorage?month=10&year=2017
13. https://www.timeanddate.com/sun/usa/anchorage?month=2&year=2017
14. https://www.ncbi.nlm.nih.gov/pubmed/4045112
15. https://smartypantsvitamins.com/vitamin-d-supplements-does-the-source-matter/