Vitamin D Deficiency

Vitamin D Deficiency

Statistics Canada found a whopping 40% of Canadians are vitamin D deficient in the winter months.

Vitamin D, or calcitriol is unique among vitamins as it acts more like a hormone. It regulates calcium in the blood and plays an important role in bone health. It also helps to keep the immune system balanced.

Vitamin D is made in our skin when exposed to sunlight. During a Canadian summer, exposing your arms and legs to the sun (without sunscreen) for 10-15 minutes provides adequate vitamin D.


What are the symptoms of vitamin D deficiency?
  • Fatigue
  • Bone or joint pain
  • Low mood, often worse in the winter months
  • Muscle weakness or cramps
  • Frequent colds and flus
Risk factors for vitamin D deficiency:
  • Reduced sun exposure
    • Living in a northern climate
    • Working indoors
  • Kidney or liver disease
    • Vitamin D is converted to its active form after passing through the liver and kidney.
  • Some medications
    • Including laxatives, Prednisone, cholesterol-lowering drugs, seizure-control drugs
  • Conditions that affect the digestive tract, such as Crohn’s or weight-loss surgery
    • This may prevent the proper absorption of vitamin D from supplements.
  • Obesity
    • Fat cells may store vitamin D, preventing it from doing its job in the body.
  • Dark skin
    • Melanin protects the skin from sun, reducing the creation of vitamin D.
  • Over 65 years of age
    • Our skin creates vitamin D, which goes through an additional conversion in the kidney to become the active form. As we age, both our skin and kidneys become less efficient at doing these tasks, increasing the risk of deficiency.
  • Use of sunscreen
    • Sunscreen protects the skin from sun exposure, this, in turn, prevents vitamin D creation.
  • Genetic Variation
    • The GC gene encodes the Vitamin D binding protein (VDBP). This little protein transports vitamin D through blood. Some individuals have a slight genetic modification in the GC gene which may require them to take higher levels of vitamin D.
What foods are rich in vitamin D?
  • Fish: Salmon, Mackerel, Tuna
  • Animal Liver
  • Eggs
  • Fortified foods: Soy, rice and dairy milk

Unfortunately, vitamin D is not abundant in plant-based foods.

What kind of supplements are used?

There are two commonly available forms of vitamin D supplements. D2 and D3. D3, cholecalciferol is three times as effective and is generally recommended.

What are some conditions vitamin D may help?


Combining vitamin D supplementation with calcium has been shown to reduce the risk of fragility fractures.


Vitamin D is important for maintaining bone health of mother and baby. Research also suggests this vitamin helps to prevent gestational diabetes, preeclampsia, bacterial vaginosis, preterm labour, and low birth weight.

Mental illnesses

Vitamin D helps to regulate two hormones which play a role in alertness, adrenaline, and norepinephrine. It also helps to prevent the loss of serotonin and supports the production of dopamine. Two neurotransmitters that are essential for mood regulation.

In addition, research has suggested there might be a connection between the severity of schizophrenia symptoms and vitamin D levels.

Multiple Sclerosis (MS)

Observational studies suggest vitamin D may play a role in the prevention of MS. Further research has found that vitamin D plays a role in reducing T helper cells and Th-17 cells, which can decrease inflammation and potentially prevent disease progression. Vitamin D may also play a role in remyelination, thereby supporting the repair of the nervous system.

Cancer Prevention

Vitamin D may play a role in the prevention of breast, colon, and prostate cancer.


Research has found vitamin D may increase insulin production in the pancreas and the expression of the insulin receptor.  It may also improve the movement of glucose into the cells by decreasing inflammation. What does this mean? Vitamin D may allow the body to use its own insulin more effectively, decreasing blood glucose and preventing long term complications.

Inflammatory bowel disease (IBD)

Up to 50% of patients with IBD may be deficient in vitamin D. Vitamin D status may also be linked to the severity of the condition. Why? Vitamin D may play a role in decreasing TNF⍺, decreases inflammation.

Can you have too much of a good thing?

Yes. Too much vitamin D can increase calcium in the blood. This can cause calcification, or hardening of the heart, kidney or lungs. Other symptoms of too much vitamin D can include confusion, depression, headaches, constipation, nausea, and feelings of thirst.

How can a healthcare provider offer support?

Based on your health history, our naturopathic doctors may recommend blood testing to identify your vitamin D level. Testing allows for a more personalized treatment protocol. This may include a vitamin D injection, supplement or lifestyle recommendations.

Our naturopathic doctors are also trained to offer genetic analysis through PureGenomics. This software allows our naturopathic doctors to look at your genetic variations related to cognitive health, weight management and your body’s unique usage of vitamins and minerals, including the GC gene.