What Is Vitamin A In International Units?

Vitamin A is the name of a group of fat-soluble retinoids. Two forms of vitamin A are available in the human diet: preformed vitamin A and provitamin A carotenoids.

IU is a unit of measurement for fat-soluble vitamins, like vitamin A.

Vitamin A is found naturally in many foods. It can also be added to fortified foods.

Getting too much-preformed vitamin A, the form found in supplements, over a prolonged period, can lead to toxicity. Supplementation should only be used periodically.

Toxicity from food sources is rare.

Vitamin A Is An Essential

Vitamin A is not just one vitamin. It is the name of a group of fat-soluble retinoids, like retinol, retinal, and retinyl esters. (source ◳)

Vitamin A is an essential nutrient that cannot be synthesized in the body. Therefore, it must be obtained through diet. (source ◳)

It plays an important role in growth, reproduction, immune function, vision, and tissue maintenance.

What is IU?

IU stands for International Units. It’s a unit of measurement for vitamins and other specific substances. It is commonly used to measure fat-soluble vitamins, like Vitamins 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 A as retinol:

From IU to mcg: IU * 0.3 = mcg

Example: 5000 IU * 0.3 = 1500 mcg

(source ◳)

Why Measure Vitamin A In IU?

International Units (IU) are a measure based on the biological activity of a substance in the body.

An IU is the amount of a substance that has a certain biological effect.

This means how much of that vitamin is going to make a difference in your body. IU measures how specific forms of vitamins are going to react in your body differently.

Foods You Can Find Vitamin A Measured In IU, In

You find vitamin A measured in IU mostly in fats and oils, american indian and alaska native food, beef, and vegetable products.

Examples of food sources include

• Cod Liver Fish Oil
• Braised Moose Liver
• Raw Beef Liver
• Raw Walrus Liver
• Freeze-Dried Sweet Red Peppers
• Braised Veal Liver
• Freeze-Dried Parsley

Foods in our nutrition tool

You can find regularly updated, top ranked lists of foods for over 200+ nutrients in our nutrition tool.

If you are interested in what foods contain the most vitamin A measured in IU, we recommend you visit our tool.

Here's our top ranked list of foods that contain Vitamin A, IU.