Vitamin D is a fat-soluble vitamin that plays a critical role in our body. From bone and muscle strength, to mood and cognitive support, vitamin D is a nutrient superstar. The sunshine vitamin is especially important for the strength of our immune system. Research shows that having healthy levels of vitamin D, as well as taking a vitamin D supplement, can help keep our immune system healthy.

Getting Our Daily Dose of Vitamin D

Since vitamin D is so important for our immune health and our health in general, we should have our levels measured regularly. The Vitamin D Council says the ideal level of vitamin D is between 40 and 80 ng/mL, with levels below 20 ng/mL as deficient. Some studies suggest intake in North America is far too low to support adequate blood levels, so a daily supplement can be a great option.

Supplement range in adults should be about 1,000 IU (25 mcg) to 10,000 IU (250 mcg), depending on our level, and 400 IU (10 mcg) to 600 IU (15 mcg) in children. Older people often need higher doses and should be measured and monitored often to be sure their daily vitamin D intake is adequate.

We should be sure the vitamin D form we're taking is vitamin D3, also sometimes called cholecalciferol. It’s the most active form of vitamin D.