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.
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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 synthesize in the body. Therefore it must be obtained through diet. (source 🗗)
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 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 A as retinol:
From IU to mcg: IU * 0.3 = mcg
Example: 5000 IU * 0.3 = 1500 mcg