Do You Know the Truth about Vitamin D?

nutrition, Torontowritten by Nicole Boyd  


What vitamin do we get less of compared to populations living closer to the equator?


With the fall making its annual appearance and the days getting a little shorter, it also means the strength of the sun's UVB rays get a lot weaker and therefore less vitamin D is produced in our body.


In case you were not aware: our body produces vitamin D when UVB rays from the sun interface with a type of cholesterol in the skin. It goes through a process in the body to create the active form of vitamin D.


There is so much talk about vitamin D, with much new research being conducted all the time.

Did you know that approximately 98 percent of what we know about vitamin D has only been discovered in the last 10 years or so?


Once thought to just assist with calcium absorption, it is now clear that vitamin D plays many more roles. I have learned quite a few things about vitamin D over the last couple years so I thought I would compile a list of 5 fun facts about vitamin D. There is so much information out there about this topic. Here is a taste:


Fun Facts About Vitamin D:


1) High deficiency rate: From November to March, if you live above 35 degrees latitude, you will not get much vitamin D from the sun. In fact, you will get next to almost nothing from the sun considering the small amount of time we spend outdoors during the winter months with bare skin exposed. We therefore must get vitamin D from food or a supplement. According to Dr. Mercola (, 85% of the entire population of the U.S. is deficient in this vitamin according to “optimal” levels in the blood . There are a few groups of people who may be at greater risk of being deficient: elderly, pregnant women, overweight individuals and people with darker skin.


2) Immune protection: Have you ever wondered why more people are sick with colds and influenza during the winter months? Vitamin D acts as a steroid hormone with potent antibiotic properties that activates special proteins to act on bacteria, viruses and fungi.


3) Vitamin D in food: There is conflicting information with regards to amounts of vitamin D in food. Vitamin D is available in limited qualities in food: eggs, mushrooms, liver and fatty fish (sardines, herring and salmon for example). I found that 115g of salmon has approximately 400 IU of vitamin D (the source did not indicate whether this was D2 or D3). Some health experts state that it is difficult to get optimal levels vitamin D from our diet. Certain foods such as cereals and milk are fortified with vitamin D. These foods are often fortified with the less active form of vitamin D- D2. Look for D3 as it is the most active form.


4) Vitamin D functions: New research has discovered that a deficiency in vitamin D can impact all 36 organs in the body. ALL cells have vitamin D receptors which means that every cell requires vitamin D for many different biological functions. Some of the functions vitamin D is needed for: immune health, cardiovascular health, cell formation, strong bones, proper digestion, healthy moods, muscles, protective effect against cancer.


5) Lots of controversy: Because vitamin D has only been heavily researched over the last 10 years or so, there is still a lot to be discovered. I found a lot of differing opinions pertaining to minimum daily amounts, adequate blood levels and whether or not food is a good source of vitamin D. Health Canada has recently raised their recommended dietary allowance (RDA) to 600 IU. Other sources such as Dr. Mercola’s website and Dr. Soram, the author of Vitamin D Revolution ( indicate that up to 2000 IUs of vitamin D should be a starting minimum amount with optimum intake at levels higher than that.


What about my Vitamin D levels?


Our government no longer pays for our vitamin D blood tests. It will cost between $32 and $93 to have this blood test performed (I will be getting tested soon so I will let you know). Ask your doctor to test blood levels of D-25 Hydroxy for the most accurate results.


I could not find what Health Canada recommends for ideal levels of vitamin D in the blood. Other medical sources such as Dr. Mercola and Dr. Soram recommend 50-65 ng/ml for optimal levels.


Because research in this field is relatively new (last 10 years or so as mentioned before) it will be up to you to decide which recommendations you are on board with. Whether you take the advice of your doctor, nutritionist, naturopath, family or friends I think it’s a good idea to keep up with the latest research as it comes forth.


It is clear how critically important the sunshine vitamin is to our health... Now get out there and grab some vitamin D!