Everything you wanted to know about Vitamin D, but were afraid to ask

Vitamin D is important for strong, healthy bones and teeth but did you know it also plays a significant role in keeping your brain, heart, lungs, muscles and immune system functioning in tip-top shape?   According to researchers at the University of Calgary, 97% of Canadians are deficient in Vitamin D!   The estimated economic impact of Vitamin D deficiency is $14 billion in healthcare costs and 37,000 premature deaths annually in Canada according to Dr. William Grant Ph.D., Director of the Sunlight, Nutrition, and Health Research Centre.  


So what is vitamin D anyway and how do I get it?

Vitamin D is a fat-soluble vitamin that plays a role in many functions throughout the body.  The body can make Vitamin D from adequate sunlight.   You can also get the “Sunshine Vitamin” in supplement form and in small quantities from a few foods such as fatty fish of fortified milk.

Whether it is synthesized from sunlight or absorbed from food or supplements, the body has to change Vitamin D into a hormone before it can be used.  So Vitamin D is actually not a vitamin at all!  This hormone is called “activated vitamin D” or “calcitriol”.


What does Vitamin D do for me?
Once it’s converted and ready to go, the body uses Vitamin D to absorb and utilize calcium and phosphorus and to help cells throughout the body communicate.  

Vitamin D is also required for the development and growth of bones and teeth, for proper thyroid functioning; it protects against muscle weakness, is involved in the regulation of the heartbeat, supports the immune system and is important in the prevention of breast and colon cancers, osteoarthritis and osteoporosis.  


I’m Canadian and not a snowbird…what do I need to know?

Our bodies make Vitamin D from a cholesterol compound in the skin when it

is exposed to UVB rays from the sun.  In Canada, the sunshine is not strong enough to provide adequate Vitamin D during the winter months.   People with darker skin have a harder time absorbing Vitamin D and those with older skin have a harder time yet.   Adding to this challenge is our attentive use of sunscreen; 93% of UVB rays are blocked by SPF 15!  Little wonder 97% of us are deficient in Vitamin D at some point during the year.


How do I avoid or combat Vitamin D deficiency?

The easy way to avoid or combat Vitamin D deficiency is to supplement year-round, particularly from October – May.   Doctors, scientists, and researchers are still discovering what the optimal dosage should be.  Factors to consider are:

  • The season;
  • How far north you are;
  • How many hours you spend outdoors during peak UV times;
  • Whether or not you apply sunscreen;
  • How pale or dark your skin is;
  • Your age;
  • Your weight;

Health Canada Recommended Daily Intake of Vitamin D

Age group Recommended Dietary Allowance (RDA) per day Tolerable Upper Intake Level (UL) per day
Infants 0-6 months 400 IU  (10 mcg) 1000 IU (25 mcg)
Infants 7-12 months 400 IU  (10 mcg) 1500 IU (38 mcg)
Children 1-3 years 600 IU (15 mcg) 2500 IU (63 mcg)
Children 4-8 years 600 IU (15 mcg) 3000 IU (75 mcg)
Children and Adults

9-70 years

600 IU (15 mcg) 4000 IU (100 mcg)
Adults > 70 years 800 IU (20 mcg) 4000 IU (100 mcg)
Pregnancy & Lactation 600 IU (15 mcg) 4000 IU (100 mcg)

The no observable adverse effect level (NOAEL) is 10,000 IU per day (Institute of Medicine Report 2010).

According to the Vitamin D Society, the best way for Canadians to determine their own personal dosage requirements is to maintain optimal Vitamin D blood levels (between 100-150nmol/L).  They encourage all Canadians to get their Vitamin D levels tested!


Types of Vitamin D

D2 (ergocalciferol) is plant-sourced and contains no cholesterol.  Until recently this was the only supplemental form for vegans but it is now understood to be inferior.

D3 (cholecalciferol) is considered the natural form and is the most active and is as much as three times more potent than D2.    D3 is synthesized in the skin and is also available in supplemental form.   D3 is sourced from lanolin (oil from sheep’s wool) and the vegan form of D3 is sourced from lichen.  Lichen is a unique combination of fungus and algae that grows on rocks and trees.


What to look for in a good Vitamin D supplement

Always, always, always look for Vitamin D3; if the label just calls the product “Vitamin D”, check the medicinal ingredients for the form.  Because Vitamin D is a fat-soluble vitamin, look for supplements that are in oil rather than tabs.  The format can be liquid or softgels, although liquids are always a little easier for the body.   Take Vitamin D with a meal containing fat to increased absorption.  

To optimize absorption, look for an Emulsified Vitamin D3.  Emulsification makes D3 easier to digest and absorb which is a benefit to anyone but is particularly import for those with malabsorption issues (Crohn’s, Celiac, Gastric Bypass, Diverticulitis, Irritable Bowel Syndrome).   Also, anyone with gallbladder issues or who have had the gallbladder removed or who has difficulty digesting fats should choose an Emulsified Vitamin D3 or take a bile salt supplement with their Vitamin D3.


What’s new with Vitamin D3 research?

Scientists are still discovering how Vitamin D works and how many body processes its effects in the body.  There is new research coming out that demonstrates just how important and how varied Vitamin D’s influence is.  Growing evidence supports that Vitamin D may play a role in preventing or reducing the severity of many conditions such as childhood asthma, some cancers, diabetes, autism and autoimmune disorders such as multiple sclerosis.   For the latest research go to the Vitamin D Society’s News Page.


FREE Vitamin D Day
Here at the Granary we’re giving away bottles of


Wednesday September 12.  

Pop in to see us and grab your free bottle!


Tuesday’s Ten: Ten Essential Vitamins

Tuesday's Ten Logo

Vitamins are essential nutrients that everyone requires for a healthy, functioning body. Here are a list of the top ten essential vitamins, their functions and the foods they can be found in.

1. Vitamin A

Good For

  • Maintaining eyesight
  • Improving immunity
  • Ensuring healthy bone development

Find it in

  • Carrots
  • Spinach
  • Sweet potato
  • Winter squash
  • Turnips

2. Vitamin B1 (Thiamine)

Good For

  • Converting carbs into energy
  • Promoting a healthy nervous system

Find it in

  • Sunflower seeds
  • Yellowfin tuna
  • Black beans
  • Lentils

3. Vitamin B2 (Riboflavin)

Good For

  • Promoting healthy skin and complexion
  • Processing macronutrients

Find it in

  • Calf’s liver
  • Milk

4. Vitamin B3 (Niacin)

Good For

  • Promoting a healthy nervous system
  • Promoting a healthy digestive system
  • Plays a key role in energy production

Find it in 

  • Chicken breast
  • Yellowfin tuna
  • Halibut
  • Turkey breast

5. Vitamin B7 (Biotin)

Good For

  • Maintaining red blood supply
  • Aiding in the absorption of other nutrients

Find it in

  • A good multivitamin, as not many foods contain significant amounts of this vitamin
  • In lower amounts find it in swiss chard, almonds, legumes, tomatoes and romaine lettuce

6. Vitamin C

Good For

  • Improving immunity
  • Protecting against cardiovascular and eye disease
  • May prevent anti-aging signs such as wrinkles

Find it in

  • Oranges
  • Strawberries
  • Brussel Sprouts
  • Broccoli
  • Red Bell peppers
  • Papaya

7. Vitamin D

Good For

  • Aiding in the absorption of calcium and phosphorus
  • Ensuring healthy bone growth

Find it in

  • Sunshine
  • Fortified milk
  • Salmon
  • Shrimp
  • Whole eggs

8. Vitamin E

Good For

  • Improving immunity
  • Promoting blood flow and healing of body tissues

Find it in

  • Sunflower seeds
  • Almonds
  • Olives
  • Spinach
  • Papaya

9. Vitamin K

Good For

  • Plays an important role in blood clotting
  • Aiding in bone development
  • Aiding in heart disease prevention

Find it in

  • Kale
  • Spinach
  • Brussels sprouts
  • Broccoli
  • Romaine lettuce

10. Folic Acid

Good For 

  • Preventing anemia
  • Aiding in new cell production
  • Especially important during pregnancy because it helps to prevent neural-tube birth defects

Find it in

  • Lentils
  • Pinto beans
  • Asparagus
  • Spinach
  • Black beans


Clark, S. (2015, April 4). The Top 10 Vitamins That Everyone Should Include In Their Diet! – Retrieved August 31, 2015.