I think a lot more people nowadays are aware of vitamin D deficiency symptoms and how most people are actually deficient in this even if they go outside a few hours a day due to having clothes on & not living near the equator (where the sun strikes at an angle that hits your skin the hardest). A study showed that ~46% of UK people aged 45 were deficient in vitamin D (under 40(OH)D nmol/L) during winter & spring months. Finally, if you wear sunscreen your vitamin D production from UVB rays is reduced by ~90% or more! I also have to mention how even those that do supplement in vitamin D probably take too little and how you can find your proper dosage.
Vitamin D is actually not really a vitamin, it’s a hormone that the sun stimulates your body into producing after your skin comes into contact with the sun’s rays and this process actually takes a while (hours) between production and its complete absorption inside our skin. For that reason its important to mention that it might be preferable to NOT go swim/shower after a good 10-30 min exposure of sun if you worry about your vitamin D levels. While this research is not full proof, it does seem that water/showers can wash away vitamin D on our skin before we absorb it so I do mention it for those like me that enjoy reading at the swimming pool everyday for some morning sun.. If you also like to go swim at the same time, you might be hurting your goal of absorbing natural vitamin D.
What does Vitamin D do?
Vitamin D (and magnesium) is one of those vitamins that’s responsible for a LOT of things and makes a huge difference once you are at adequate levels. The biggest? I practically almost never get colds now… And when I do the symptoms are quite mild. This might partly be one of the benefits of vitamin C from the high amount in my diet from all the vegetables I eat but in my friends that do not eat “as well” as me (aka grains/baked goods devoid of vitamins/minerals), they still saw huge improvements from taking vitamin D supplements. The other more well known benefit nowadays is directly related to calcium and bones. Most people have been hammered to death, especially by milk advertisements, how calcium is good for growing tall and strong… The truth is, yes calcium is useful but without other important nutrients such as vitamin D, Magnesium and vitamin K2 it does not work optimally.
By having adequate levels of vitamin D you of course reduce your risk of any of the following vitamin D deficiency symptoms, some of these are taken from webMD:
- Increased risk of death from cardiovascular disease
- Cognitive impairment in older adults
- Severe asthma in children
- Birth defects if you are pregnant (Dave Asprey made a great post here summing up why pregnant women REALLY need to make sure they are not staying home all day and night)
- Many other things that are probably hard to directly correlate to vitamin D with 99% confidence
If you had to choose 2 vitamins/minerals you have a high chance of currently being deficient in, this is one of them! Magnesium would be another. You need to be near the equator to have a sun strong enough to give you UVB rays to produce vitamin D all year long, if you did not build enough reserves the more far North you are the more you risk being very deficient during winter months (or summer of course if you barely go outside, wear sunscreen or are often fully clothed)
Alright Alex, you convinced me vitamin D deficiency is bad… What’s a good dose??
This changes from person to person. I don’t really count the vitamin D I get from food, it’s too little and chances are your body is meant to get a large amount of it from the sun. I eat a lot of eggs however and they do contain vitamin D, but I don’t drink milk, which is a good source especially since a lot of manufacturers are fortifying it with extra vitamin D, since a lot of research I’ve seen points to normal industrial milk to have quite a lot of potential side effects. Ideally if you stay indoors like me most of your days (especially during the winter) you probably can safely take 5,000-10,000 IU. During the summer I usually work on my laptop 1-2 hours outside topless (looking hot + more skin is exposed to the sun to make some vitamin D) so I only take 5,000. It’s currently the winter and I’m taking 8,000IU in the morning with my first meal. I currently take the now foods brand because it’s a generally good quality brand and they offer vitamin D3 in soft gel form which is better for absorption. However, vitamin d3 unlike other supplements is usually more consistent in quality across brands so you don’t have to worry too much about it. The difference mostly comes from how much your body can absorb from it during digestion. You can also find vitamin D2 as a supplement but a vitamin D3 supplement is better absorbed as this study shows.
This is only a guideline though, eventually you want to get tested because you can have a big variance depending on your skin color, daily activities & vitamin D3 supplement quality. You can get some at home kits from the ZRT lab in association with the nonprofit vitamin D council, kinda expensive at $65 each but I’m a nerd and I bought 3 packs a few months ago to test at different intervals during the summer and winter. Doctors can also do this test live, request a 25-hyrdroxy-vitamin D (25D) test, hopefully your insurances cover it! I have none since I never get sick and I live in socialist Canada for serious injuries. My fall test put me at 69 ng/mL and while there seems to constantly be controversy over the best optimal range, overdosing on vitamin D is actually a legitimate risk so I’m now aiming for 50 ng/mL during the winter. It’s hard to be 100% certain on the optimal dosage, one study shows how groups going to as high as 80 ng/mL keep on living stronger and stronger. While other Studies have shown that bone density peaks at around 45 ng/mL and goes down after. Since I get practically no sun my next test results will most likely be lower even if I upped my dosage from 5,000IU to 8,000IU. Half an hour to an hour in the sun should produce 10,000 IU in ideal conditions but this means being light skinned & not blocking the sun from reaching your skin (clothes and windows). Office/car windows do not count, while the sun reaches you it’s only the stronger UV rays that risk giving you cancer, the ones that produce vitamin D are sadly blocked by the window. You actually get the worst deal but hey, at least you see some sunlight ;).
When should you take your vitamin D supplement?
In the morning, always. If you track your sleep patterns with a zeo (I do). You might notice that if you take vitamin D later in your day or before going to bed your sleep patterns seem affected a bit. Besides, it makes sense that your body would use vitamin D as a signal to be awake and the sun is up anyway. It’s fat soluble so I take it with my first meal which usually has butter/coconut milk in my coffee and I often have eggs & bacon too.
Awesome, gonna take my supplements and stay home all day like you!
Hmmmm, I want to point out that their are studies out there showing how you STILL definitely want to get some sunlight or safe UV radiation every now and then. Vitamin D from the sun is a bit different from the supplement form & also the sun has many other advantages for your health. The most obvious one is how it directly affects your mood, I’m sure their are a lot of other subtle ones we don’t notice as easily. Dr Cannell from the vitamin D council does UV radiation during the winter… I think that’s a bit extreme but I wanted to link to his post because it shows the importance of going outside every now and then if you want to read further on the topic.
Also Dr Cannell wrote a great paragraph in a yahoo news article of an experiment showing that Vitamin D deficiency heavily correlates with dementia, if anything this will help convince you of how important it is!
“People tend to not believe vitamin D news, because it seems too good to be true,” John Cannell, MD, executive director of the California-based nonprofit Vitamin D Council, told Yahoo Health. “But vitamin D has a profound mechanism of action, as it’s really a steroid hormone that turns genes on and off, and no other vitamin works that way. There are at least 1,000 different genes directly influenced by vitamin D.” The council recommends a combination of cautious sun exposure combined with supplements in winter months.