Retinol: What is the Chemical Name of Vitamin A and Its Deficiency Disease?

December 25, 2025 •

4 min read

Vitamin A deficiency is the leading cause of preventable blindness in children worldwide, affecting hundreds of thousands annually. A critical nutrient for human health, this fat-soluble vitamin plays a vital role in vision, immune function, and cellular development. However, a lack of it can lead to serious health complications, with the most well-known being a detrimental eye disease.

Quick Summary

The chemical name for vitamin A is retinol, and its deficiency can cause a variety of health problems, most notably night blindness and other eye issues. This article examines the roles of vitamin A, its common deficiency symptoms, and provides a list of foods high in this essential nutrient.

Key Points

Chemical Name: The primary form of vitamin A is chemically known as retinol, and the name derives from its function in the retina.
Deficiency Disease: The main disease caused by vitamin A deficiency is xerophthalmia, a severe eye condition that can lead to blindness.
Early Symptom: An early and reversible symptom of xerophthalmia is night blindness, which impairs vision in low light.
Two Forms: Vitamin A is found in two forms in food: preformed vitamin A (retinol) from animal products and provitamin A carotenoids (like beta-carotene) from plants.
Other Effects: A deficiency can also cause skin issues, weakened immunity, reproductive problems, and stunted growth.
Risk Populations: Vitamin A deficiency is a major public health issue in developing countries, affecting many children and pregnant women.
Prevention: Eating a balanced diet rich in both animal and plant sources of vitamin A is the best way to prevent deficiency.

The Chemical Identity of Vitamin A: Retinol and its Relatives

Vitamin A is not a single compound but rather a group of fat-soluble retinoids, with retinol being the most commonly recognized chemical name. The name 'retinol' comes from its function in the retina of the eye, where it is converted into the retinal, an essential component of the light-sensitive molecule rhodopsin.

Other forms of vitamin A

Preformed Vitamin A: These are retinoids such as retinol and retinyl esters found in animal products and fortified foods.
Provitamin A Carotenoids: Plant-based pigments, such as beta-carotene, that the body can convert into vitamin A.

The body's conversion process

When you consume provitamin A carotenoids, your body converts them into the usable forms of vitamin A. Beta-carotene is the most common and effective of these provitamin A compounds. This conversion takes place in the intestines via the enzyme beta-carotene monooxygenase. The rate of conversion can vary from person to person.

The Disease Caused by Vitamin A Deficiency: Xerophthalmia

The most significant and identifiable disease caused by vitamin A deficiency is xerophthalmia, a progressive eye disease that begins with night blindness. The word "xerophthalmia" literally means "dry eyes" and perfectly describes the condition's progression.

Stages of xerophthalmia

Night Blindness (Nyctalopia): This is often the first symptom, where an individual has difficulty seeing in low-light conditions. This happens because the retina has insufficient vitamin A to produce rhodopsin, the pigment needed for low-light vision.
Conjunctival Xerosis: The thin membrane covering the white of the eye (the conjunctiva) becomes dry, thick, and wrinkled.
Bitot's Spots: These are characteristic, foamy, white or yellowish patches that appear on the conjunctiva. They are made of a build-up of keratin and shed epithelial cells.
Corneal Xerosis: The cornea itself, the transparent front part of the eye, becomes dry and cloudy.
Keratomalacia and Ulceration: In the most severe cases, the cornea softens and ulcerates, which can lead to infection, scarring, and irreversible blindness.

Beyond Vision: Other Symptoms of Vitamin A Deficiency

While eye problems are the most famous consequence, a lack of vitamin A can affect many other bodily systems.

General health impacts

Compromised Immune Function: Vitamin A plays a critical role in the development and distribution of T and B cells, which are crucial for immune response. A deficiency can lead to an increased susceptibility to infections, especially in the respiratory and gastrointestinal tracts.
Skin Issues: The skin can become dry, scaly, or rough, a condition known as follicular hyperkeratosis or phrynoderma. This is caused by the overproduction of keratin that blocks hair follicles.
Reproductive Problems: Vitamin A is essential for both male and female reproduction and for proper fetal development. A deficiency can lead to infertility and increase the risk of complications during pregnancy.
Stunted Growth: In children, vitamin A deficiency is associated with delayed or stunted growth.
Anemia: A link exists between vitamin A and iron metabolism; deficiencies in vitamin A can precipitate iron deficiency anemia.

Comparison of Vitamin A Sources

To prevent deficiency, it's essential to consume a diet rich in vitamin A from both animal and plant sources. The body utilizes these different forms with varying efficiency.


Feature	Preformed Vitamin A (Retinol)	Provitamin A Carotenoids (e.g., Beta-carotene)
Source	Animal products (liver, fish oil, eggs, dairy)	Plant-based foods (carrots, spinach, sweet potatoes)
Active Form	Active upon consumption	Needs conversion to retinol by the body
Conversion Efficiency	100% efficient	Less efficient and variable among individuals
Storage	Stored in the liver as retinyl esters	Stored in fat tissue and can cause harmless yellowing of skin at high intake
Toxicity Risk	High intake can be toxic (hypervitaminosis A)	Low risk of toxicity; high doses in smokers linked to increased lung cancer risk

Prevention and Treatment

Prevention is the most effective approach to managing vitamin A deficiency. A balanced diet incorporating foods from both animal and plant sources is key. For at-risk populations in developing countries, public health interventions like supplementation programs have proven highly effective. For those with established deficiency, treatment typically involves high-dose vitamin A supplementation under medical supervision to rapidly restore body reserves. Early detection is crucial, as some forms of vision damage, such as corneal scarring, are irreversible.

Conclusion: The Importance of Knowing Vitamin A's Role

The chemical name of vitamin A is retinol, and its most serious deficiency-related disease is xerophthalmia, a progressive and potentially blinding condition. The signs and symptoms extend beyond vision to include weakened immunity, skin problems, and impaired growth. By understanding the two forms of vitamin A, their dietary sources, and the risks associated with inadequate intake, individuals can make informed dietary choices to protect their health. Early intervention is vital to prevent irreversible damage, particularly to vision. For more information on dietary sources and daily requirements, consult resources from organizations like the National Institutes of Health.

Frequently Asked Questions

The common name for vitamin A is retinol, which is the preformed, active form of the vitamin found in animal products.

The main functions of vitamin A include promoting healthy vision, especially in low light, supporting the immune system, and maintaining healthy skin and mucous membranes.

Yes, chronic and severe vitamin A deficiency can lead to xerophthalmia, which progresses to corneal damage and can result in irreversible blindness if left untreated.

Good sources of vitamin A include animal products like liver, eggs, and dairy, as well as plant-based foods rich in carotenoids such as carrots, sweet potatoes, and spinach.

Retinol is a form of preformed vitamin A found in animal products, while beta-carotene is a provitamin A carotenoid from plants that the body converts into retinol.

Infants, young children, and pregnant or breastfeeding women, particularly in developing countries, are most vulnerable to vitamin A deficiency due to limited dietary intake.

Yes, excessive intake of preformed vitamin A (retinol), usually from supplements, can cause toxicity (hypervitaminosis A). This is especially a concern during pregnancy as it can cause birth defects.