Are you on your daily dose of vitamin D yet?
If not, you are missing out. Common belief is, that vitamin D is only relevant for bones, but it can do so much more.
Vitamins, by definition, are essential for life and cannot be produced in the body, but have to be ingested. Fact is, that under the right circumstances vitamin D actually can be produced in the body. At the same time you could argue, that the conditions to produce it are only there half of the year (at least in our latitudes). I’ll get to that later. The reasons, why it has been classified as a vitamin, are historical. Because we know more today than we did when it was discovered, we consider it now a pro-hormone.
It’s essential for calcium metabolism, without it we can’t build bones. One of the most important molecules vitamin D has a strong relationship with is calcium. With enough vitamin D in your system you will be able to absorb and transport calcium into your body. Calcium on the other hand is an important nutrient, not only for bones, but also for nerve and muscle function.
This is the reason why you can develop muscle and nerve pain when you are deficient in vitamin D. So if you are suffering from aches and pains, you should also check your vitamin D levels.
Little known vitamin D effects
But that’s still not all. The interest in vitamin D has been huge over the last decade. Meanwhile numerous studies are showing a benefit of vitamin D intake to prevent infections, allergies and … even cancer, as vitamin D has been shown to be a powerful gene modulator. Vitamin D is also an important immune modulator, meaning that it will boost your immune system when required but also make sure that your immune system is not overreacting, as in autoimmune diseases.
Being a big player in the bodies biochemistry it also has an important role in the hormone metabolism. There is an inverse relationship with estrogen, which explains, why good vitamin D levels seem to be preventive of breast cancer.
Vitamin D and sun light
Now, here’s the thing. While dietary sources of vitamin D are scarce (you may be fine if you ate about half a kg of salmon or mackerel a day), our bodies are actually able to produce vitamin D. Great, isn’t it? But the problem is that we need UV-B sunlight on bare skin to do that. Why is that a problem? Because in winter UV-B sunlight is reflected in the atmosphere and therefore doesn’t come down to the ground. The closer you live to the poles, the longer the time frame during which this happens. In Ireland between September to March you will find it impossible to build enough vitamin D. Therefore our vitamin D levels drop gradually over the winter and, when tested by a blood test, will be lowest around March.This is particularly relevant in winter when most people, who don’t supplement, would be vitamin D deficient. That’s one reason why we tend to be more prone for flues and other viral infections (including SARS-COV-2) in the winter time.
The other problem is that, once sunlight is available again, many of us tend to lash factor 50 (sun cream) on to prevent sun damage. Or many would work all day in the office and not get exposed to the sun in the first place. Unfortunately this behavior will let you miss out on all the positive effects from good levels of vitamin D. You (and your dermatologist ) might say now, that the sun is dangerous for your skin and can cause skin cancer. While that is true, you have to put it into perspective.
First of all I recommend not to get a sunburn, but instead I recommend responsible sun exposure, as much as tolerable. Second, it’s the less dangerous white skin cancer, that is caused by sun damage, while melanoma very often develops in areas, that are rarely exposed to the sun. On top of all that, good levels of vitamin D seem to be protective of cancer, including skin cancer. The best time of the day and year to acquire good vitamin D levels is between 10 a.m. and 3 p.m. from April till August.
What vitamin D level should we aim for?
The labs lower limit is usually a 50 mmol/l, which will prevent acute osteomalacia in adults or rickets in children. But as I explained above, vitamin D has so many more functions, that can’t be fulfilled at this rather low level. Therefore, in my opinion anything between 75 mmol/l and 200 mmol/l can be fine and will be well tolerated. That said, there are people that will do better on the higher end of the spectrum and others will be fine on the lower end. We are all individuals and as such have different requirements. So get tested and take vitamin D, now!