What are the sources of Vitamin D? ​

Vitamin D is produced by our skin when it’s exposed to UVB rays from the sun – this is usually our main source of Vitamin D. Health professionals suggest that 5–30 minutes in the sun between 10 am to 3 pm, without sunscreen, could provide our entire daily intake needs.^1,2 But many of us spend most of our time indoors, especially during this pandemic, and we all know that excessive sun exposure without sun protection increases the risk of skin cancer, so we don’t always get enough sun exposure to meet our Vitamin D needs.²

Diet can be another source of Vitamin D, although few foods naturally contain Vitamin D. Protein from fatty fishes and fish liver oils is especially high in this nutrient.¹ Some food products, such as milk, cereals, and fat-containing spreads, are also usually fortified with Vitamin D.³ Although one tablespoon of cod liver oil would supply more than enough Vitamin D for a day,¹ not many people like eating it!

Other foods that could meet an adult’s daily needs (i.e., at least 600 IU) include¹:

• about 90 g of cooked salmon
• 5 cups of Vitamin D-fortified milk
• 14 large eggs
• 12 cans of tuna fish!

You can see that most foods just don’t contain enough Vitamin D to easily meet our recommended daily allowances.

If the sun and our diet are not providing enough daily Vitamin D, Vitamin D supplements could be the answer. There are two main types of Vitamin D supplements: products that can be purchased over the counter at pharmacies or supermarkets, and medications containing much higher doses that doctors prescribe to treat Vitamin D insufficiency or deficiency.

Since Vitamin D is a fat-soluble vitamin, the body absorbs it best from the gut when it is combined with some fat.⁴ That’s why oral Vitamin D supplements should be taken with a meal containing healthy fats and why some supplements are made as oil-based formulations that will aid absorption regardless of food intake.^3,4