What Name is Vitamin A Also Known As?

December 8, 2025 •

3 min read

According to the World Health Organization, vitamin A deficiency is the leading cause of preventable blindness in children globally. One of the most important nutrients for vision and overall health, vitamin A is also known by several other names, depending on its specific chemical form.

Quick Summary

Vitamin A, a fat-soluble nutrient, is also referred to as retinol, and exists in various forms within the body and diet. These different compounds are collectively known as retinoids. Plant-based sources provide provitamin A carotenoids, such as beta-carotene, which the body converts into active vitamin A.

Key Points

Primary Name: Vitamin A is also known by the scientific term 'retinol' because it produces pigments in the eye's retina.
Two Main Types: Dietary vitamin A is available in two forms: preformed vitamin A (retinoids from animal sources) and provitamin A (carotenoids from plants).
Essential for Vision: A primary function of vitamin A is its role in vision, particularly low-light vision, and in maintaining healthy eye tissues.
Crucial for Immunity: It is vital for a healthy immune system, supporting the growth and function of white blood cells that fight infection.
Plant-Based Precursor: Beta-carotene is the most common provitamin A carotenoid, found in colorful fruits and vegetables, which the body can convert to retinol.
Risk of Toxicity: Excessive intake of preformed vitamin A, usually from supplements, can be toxic and lead to hypervitaminosis A.
Safe from Plant Sources: It is nearly impossible to reach toxic levels of vitamin A from carotenoids alone, as the body regulates the conversion process.

The Different Forms of Vitamin A: Retinoids and Carotenoids

While “vitamin A” is the common term, it actually refers to a group of fat-soluble compounds called retinoids. The most notable form, which is also the most potent, is retinol. This is because retinol is the active form that the body can use directly. In contrast, plants contain provitamin A carotenoids, like beta-carotene, which the body must convert into retinol. The name "retinol" comes from its role in producing pigments in the retina of the eye, which are essential for vision, especially in low light.

How Your Body Uses Different Forms

The two main categories of vitamin A—retinoids and carotenoids—are processed differently and have different effects on the body. Retinoids, found in animal-based foods, are readily absorbed and used. Carotenoids, from plant-based sources, have a more complex journey. The efficiency of converting carotenoids to retinol can vary between individuals due to genetics or other health factors. For example, people with cystic fibrosis may have trouble absorbing fat-soluble vitamins, including vitamin A.

Retinoids: The active forms of vitamin A, including retinol, retinal, and retinoic acid. They are found in animal-derived foods and fortified products, and they are stored in the liver.
Carotenoids: Plant-based pigments that act as precursors to vitamin A, with beta-carotene being the most well-known. They are abundant in brightly colored fruits and vegetables.

Health Benefits of Vitamin A

The diverse forms of vitamin A contribute to a range of vital bodily functions. From supporting immune function to maintaining healthy skin, its benefits are far-reaching. Here is a list of some of the key health benefits associated with sufficient vitamin A intake:

Vision and Eye Health: Vitamin A is a key component of rhodopsin, the protein in the eye that allows for low-light vision. It also protects the cornea and conjunctiva.
Immune System Support: It is critical for the function of white blood cells, which protect the body from infections.
Growth and Development: It is essential for cellular growth and differentiation, making it crucial for healthy fetal development and childhood growth.
Skin Health: Vitamin A promotes the health and maintenance of epithelial tissues, including the skin, and plays a role in producing sebum to keep skin and hair moisturized.
Antioxidant Properties: Provitamin A carotenoids like beta-carotene act as antioxidants, protecting cells from damage caused by free radicals.

Comparing Retinoid and Carotenoid Sources

It is useful to understand the differences between the two main types of vitamin A sources when planning your diet. The following table provides a clear comparison to help you distinguish between them and make informed dietary choices.


Feature	Retinoids (Preformed Vitamin A)	Carotenoids (Provitamin A)
Source	Animal-based foods (e.g., liver, eggs, dairy, fish oils).	Plant-based foods (e.g., carrots, sweet potatoes, spinach).
Conversion	Active form; no conversion needed.	Inactive form; must be converted to retinol.
Bioavailability	High; readily absorbed.	Lower; absorption and conversion efficiency vary.
Toxicity Risk	High; excessive intake can be toxic.	Very Low; toxicity from food sources is rare.
Safety	Requires careful monitoring, especially with supplements.	Generally safe, even in large quantities from food.

The Risks of Vitamin A Imbalance

Maintaining the right balance of vitamin A is crucial, as both deficiency and toxicity can lead to serious health problems. Deficiency is the more widespread issue globally, but toxicity can occur, particularly from over-supplementation with preformed vitamin A. Excessive intake can lead to a condition called hypervitaminosis A, which causes symptoms like headaches, dizziness, hair loss, and liver damage. In contrast, excess carotenoids generally lead to a harmless yellowing of the skin called carotenemia.

Conclusion

In conclusion, while the common name for vitamin A is often associated with retinol, it encompasses a broader group of compounds. Retinoids, including retinol, are the active form found in animal products, while carotenoids, like beta-carotene, are plant precursors that the body converts. Understanding these different forms is key to appreciating how vitamin A supports essential functions like vision, immune response, and cellular growth. A balanced diet rich in both animal and plant sources is the best way to ensure adequate intake without risking toxicity, while supplementing should be done under medical guidance. To learn more about the specific dietary guidelines and functions, you can refer to the National Institutes of Health website.

Frequently Asked Questions

The most common name for vitamin A is retinol, referring to the active form of the vitamin that the body can use directly.

Retinol is a specific, active form of vitamin A found in animal products, but the term vitamin A also includes other related compounds called retinoids and plant-based carotenoids.

Retinoids are preformed vitamin A found in animal products and can be used immediately by the body. Carotenoids are provitamin A found in plants that must be converted into retinol by the body.

Provitamin A carotenoids, with beta-carotene being the most common, are the form of vitamin A derived from plant sources such as carrots, sweet potatoes, and spinach.

Vitamin A is essential for creating the pigments in the retina needed for vision, especially in dim light. It also helps maintain the health of the cornea and conjunctiva.

Yes, excessive intake of preformed vitamin A (from animal products or supplements) can be toxic, a condition known as hypervitaminosis A. However, toxicity from plant-based carotenoids is rare.

Some foods, such as milk and cereals, are fortified with retinol to help ensure people meet their daily recommended intake of vitamin A, especially in populations where deficiencies may be common.