Vitamin D is undeniably important for supporting our physiology. Considered both a vitamin and a hormone, this nutrient is found in certain foods and is also synthesized by the skin when exposed to sunlight.
Among the many benefits of vitamin D, most notable is its ability to maintain strong bones & muscle strength, its anti-inflammatory effects, its mood supporting properties, its ability to optimize immune function, promote balanced blood sugar levels, and support cardiovascular health.
In order to determine if your vitamin D levels are normal, regular blood testing is necessary. I typically recommend patients have their levels tested twice per year in Canada - once in the fall and once mid-winter. I highly recommend having your levels tested if you experience the “winter blues”, frequent infections, colds, or the flu, if you are post-menopausal, suffer from chronic disease, or if you are at risk of low bone density/osteoporosis. Once you have your levels tested, you and your health care provider can better understand your needs.
The following are ways to increase and maintain normal vitamin D levels with foods and nutritional supplements:
Cod liver oil
Organ meats (ex. beef liver)
Consuming a variety of vitamin D rich foods can be helpful for supporting healthy vitamin D levels. With that being said, it is challenging to obtain enough Vitamin D solely through food, especially if you live in a colder climate with less sunlight.
Vitamin D & Sun Exposure
As vitamin D is hard to obtain in adequate amounts through diet, it is helpful to regularly expose unprotected skin (ie. no sunscreen or clothing average) to the sun. 10 minutes of unprotected sun exposure early each day (preferably before 10AM) on as much skin as possible is ideal. Note: it is imperative to avoid burning. If you feel the skin turning red, becoming very hot, or burning, remove yourself from the sun right away as this is a sign that you need to scale back and start with a shorter duration. For fairer individuals, you can start with as low as one minute per day and work up to 10 minutes.
Because humans largely rely on the sun as their “source” of vitamin D, those who spend most of their time indoors or who live in climates where sunlight is limited in the winter will inevitably experience a seasonal drop in their blood levels of vitamin D, without adequate supplementation.
It is important to note that not all skin types will synthesize vitamin D in the same way. The darker your skin tone, the more melanin you have. Melanin serves as a natural SPF of sorts which helps to prevent sun damage - while also preventing the skin from synthesizing as much vitamin D. Fairer skin tones do not produce as much melanin, but are also more likely to burn when exposed to the sun unprotected. Either way, supplementation with vitamin D is integral and the best way to understand your needs is to have your blood tested.
Supplementing with Vitamin D
Vitamin D is a fat-soluble vitamin, meaning it is best absorbed in fat or alongside a source of fat. When selecting a supplement, it is important to choose either a soft gel or liquid that has a fat as its base. Coconut oil, MCT, and/or olive oil are all excellent ingredients to look for. Alternatively, a term to look for is “emulsified”. If you are able to take an emulsified vitamin D preparation, this will help the vitamin be readily absorbed into the system.
There are various vitamin D supplements on the market — some contain vitamin D2 and others contain vitamin D3. Some evidence suggests that supplementing with the D3 form increases blood levels of vitamin D more rapidly and sustainably.
Another consideration is selecting a vitamin D supplement that includes vitamin K2. Vitamin K is another important nutrient in the body and it works synergistically with vitamin D. Finding a supplement that contains both can be helpful, particularly if maintaining and improving bone density is one of your primary goals.
Overall, vitamin D supplementation is very safe and appropriate for all ages, with different age groups requiring different dosages. Taking high doses of Vitamin D does not always yield a greater benefit; you have to supplement according to your needs. There is no one dosage that fits all. This is why it is always important to have your blood levels checked at regular intervals to ensure you are within a healthy range, and from here, supplement accordingly.