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Advice from a Naturopathic Doctor in Toronto: Dealing with Vitamin D During Wintertime


Our clinic’s naturopathic doctor in Toronto advises Canadians on why they need to consider vitamin D supplementation in the wintertime. It is because the body can produce vitamin D efficiently during the summer months. But with grey skies during the wintertime, Canadians need to pay attention to their vitamin D levels. A vitamin D deficiency may cause various side effects, including depression, bone and muscle pain, cramping and/or weakness.

Below are some relevant facts about Vitamin D and its impact on health, as well as recommendations from our Toronto Naturopath on how you may find alternative supplementation.

Why is vitamin D called the “sunshine vitamin”?

Vitamin D is a fat-soluble vitamin that is naturally obtained from exposing uncovered skin to sunlight. In particular, ultraviolet B (UVB) rays shine onto the skin; the skin then generates a precursor that is altered into an active vitamin D form in the kidneys and liver.

Vitamin D supports bone health; it also helps with the absorption and retention of calcium and phosphorus in the body. Many tissues and organs in the human body have vitamin D receptors, denoting the vitamin’s critical roles in insulin regulation, fertility support, cardiovascular health, and immune, brain, and nervous system support.

Vitamin D may bring additional support to the immune system

Did you know that studies have linked vitamin D deficiencies to respiratory tract infections, including the common cold, bronchitis and pneumonia? It’s safe to say that vitamin D supplements may impact your health during cold and flu season and beyond.

One of the roles of this vitamin includes keeping your immune system strong to ward off viruses and bacteria. Vitamin D interacts with the body’s antimicrobial activity in our innate immune cells, prompting the fight against infections.

Vitamin D has also been shown to enhance antimicrobial peptides, molecules that defend our cells from bacterial “invaders”. Hence, it’s suggested that there’s a molecular basis for vitamin D protecting the body against bacteria and viruses.

Vitamin D may help you deal with the “winter blues”

Suffering from the winter blues? Some Canadians experience this from a lack of sun exposure, resulting in prolonged sadness. Seasonal changes in vitamin D levels suggest the possibility that supplementation may help with issues such as seasonal mood disorders.

In fact, “Several studies showed a significant relationship between vitamin D deficiency and late-life depression in northern latitudes,” explains an article in Neuropsychiatry. The article goes on to say, “In further assessment of an older population-based cohort living at northern latitudes, a moderate inverse relationship between vitamin D serum level and depressive symptoms was observed among both genders.”

However, additional studies need to be conducted on specifically preventing or treating depression with vitamin D. Meanwhile, research continues to suggest that depression and vitamin D deficiencies are connected.

Vitamin D may help reduce muscle and back pain from a vitamin D deficiency

Did you know that bone, leg, shin and/or low back pain, combined with fatigue, may be a sign of insufficient vitamin D levels in the blood? In one controlled study, participants deficient in vitamin D were almost twice as likely to have achy joints, ribs or legs in comparison to those with normal-range blood levels.

If you’re indoors during most of the winter season and you have body pain, you may want to discuss vitamin D therapy with your naturopathic doctor in Toronto. According to Frontiers in Immunology, “Several studies indicate that vitamin D supplementation and/or deficiency changes the gut microbiota profile; as such, this can potentially modulate visceral pain.”

Many are surprised to learn that muscle pain may be related to vitamin D deficiencies. Some health care practitioners believe this may be common for patients with muscle knots (also known as “trigger points”). More research needs to be shepherded on this thought, but vitamin D may help scientists understand this further.

On the plus side, vitamin D supplementation may help improve muscle strength. As reported by Nutrients, “Studies have demonstrated that vitamin D supplementation can improve muscle strength which in turn contributes to a decrease in incidence of falls, one of the largest contributors to fracture incidence.”

Where to find vitamin D sources

It’s possible to improve your vitamin D levels. Naturopathic doctors would suggest eating D-rich foods, such as fatty fish (i.e. salmon and arctic char), fish oil, fortified milk, egg yolks, and fortified breakfast cereals.

Nevertheless, vitamin D isn’t always accessible through diet, especially if you’re vegan or lactose intolerant. So vitamin D liquid or gel capsules are recommended. Unlike tablets, liquid or gel capsules are efficient for bodily absorption. When choosing a vitamin D supplement, look at the product’s certificate of analysis. This ensures that third-party groups have tested the product for safety and that your product is free of contaminants. If you can’t find the certificate of analysis, call the supplement company to request this.

Finally, ask your naturopathic doctor in Toronto about vitamin D supplements. Vitamin D supplementation is also available via intramuscular injections, which are available at Toronto Functional Medicine Centre, a naturopathic medicine clinic located at the heart of Toronto, Ontario. High-dose vitamin D may be injected into the muscle, which gradually releases the vitamin through the bloodstream.

Are you at risk of a vitamin D deficiency?

Vitamin D deficiency is surprisingly common. Unfortunately, it’s hard to pinpoint when it’s an issue, especially since symptoms may feel minimal by those who are affected. If you have health concerns or is concerned about a vitamin D deficiency, please speak to your health care practitioner. Currently, our naturopathic doctor in Toronto is accepting new patients; strict COVID-19 protocols are in place. By applying integrative functional medicine, our clinic embraces individuality; all of our natural treatments take your lifestyle and biology into consideration.

Do you have questions about our other services? Our Toronto Naturopathic clinic is open from Mondays to Saturdays. If you have health goals and in need of assistance in achieving optimal health, our naturopathic therapies may be able to help you. Please call (416) 968-6961 to book your appointment.



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