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What Is Vitamin D In International Units?

Here you can read about what vitamin D is, both D2 and D3, measured in International Units (IU).

Vitamin D exists in two forms, Vitamin D2 and Vitamin D3. Despite its name, vitamin D is not a vitamin. It is a hormone that can be synthesized by sunlight.

It is fat-soluble vitamin, which means that the body does not need these every day. We have the potential to store it in our bodies.

Vitamin D2 And Vitamin D3

Vitamin D exists in two forms. Vitamin D2 and Vitamin D3. (source 🗗)

There are a few differences between the two D vitamins. You can read more on Vitamin D, D2 and D3.

It's difficult for people to get enough vitamin D from food alone.

Supplements are an alternative, but taking too many vitamin D supplements over a long period can cause too much calcium to build up in the body. So be careful and take the right amount.

International Units

IU stands for International Units. It is a unit of measurement for vitamins and other specific substances. It is commonly used to measure fat-soluble vitamins, like Vitamin A, D, and E.

Vitamins are measured in milligrams, micrograms, or international units. Milligrams and micrograms show the amount of mass in a sample. But international units show the level of biological activity of the substance. (source 🗗)

For unit conversion, the formula is:

To convert Vitamin D:

From IU to mcg: IU * 0.025 = mcg

Example: 400 IU * 0.025 = 10 mcg

(source 🗗)

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Sara Niemelä

co-founder Care Omnia, Head Content Creator

I’m a wife and a mother of three. I enjoy the outdoors, cooking, and spending time with my family. Nutrition is my passion. I have spent thousands upon thousands of hours reading, analyzing, categorizing and comparing research studies. Nutrition is the foundation you build a healthy and fulfilling life upon!