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Vitamin D, also known as the sunshine vitamin, is one of the essential vitamins that people need to acquire, primarily through their diet and exposure to sunlight. It is responsible for many functions inside the human body, the most important of which is to increase the absorption of calcium from food, needed for strong bones. Almost 50% of the population worldwide has a vitamin D insufficiency, while an estimated 1 in 7 suffer from vitamin D deficiency. These trends can be attributed partly to lifestyle changes in recent generations (such as reduced outdoor activities) as well as environmental changes (such as air pollution) that can limit one’s exposure to sunlight. Vitamin D is primarily produced in the human body as a direct result of exposure to ultraviolet-B rays from sunlight. Some foods are also fortified with vitamin D, for example cow’s milk.

Vitamin D Deficiency

The Health Canada guidelines for vitamin D supplementation state that each and every one of us should be acquiring a particular amount of international units (IU) of the vitamin depending on age (see table below). People that are deficient in the vitamin should talk to their doctor, who will likely recommend a dose closer to three to four times the daily recommended intake until the deficiency is normalized. Canadians are at particular risk of vitamin D deficiency due to the geographical location of the country, should consider getting a blood test done to check their vitamin D levels, and start supplementation if needed.

Health Canada Guidelines for Vitamin D Supplementation

Age group

Recommended Dietary Allowance (RDA)
per day

Tolerable Upper Intake Level (UL)
per day

Infants 0-6 months400 IU (10 mcg)1000 IU (25 mcg)
Infants 7-12 months400 IU (10 mcg)1500 IU (38 mcg)
Children 1-3 years600 IU (15 mcg)2500 IU (63 mcg)
Children 4-8 years600 IU (15 mcg)3000 IU (75 mcg)
Children and Adults
9-70 years
600 IU (15 mcg)4000 IU (100 mcg)
Adults > 70 years800 IU (20 mcg)4000 IU (100 mcg)
Pregnancy & Lactation600 IU (15 mcg)4000 IU (100 mcg)


Health Canada. (2019). Vitamin D and Calcium: Updated Dietary Reference Intakes.

If you have any questions or client issues regarding this article or its contents, feel free to reach out directly to Rx Infinity or contact us here at ASSOCIUM and we will facilitate the connection or you. If your issue or question is specific to your personal and prescribed medication, please contact your physician or your providing pharmacy.

This information is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health provider with any questions about your medical condition. Do not disregard professional medical advice or delay seeking advice or treatment because of something you have read here.

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