What Are the First Two Signs of Vitamin A Deficiency?

November 13, 2025 •

3 min read

Worldwide, a vitamin A deficiency is the leading cause of preventable childhood blindness. The first two signs of vitamin A deficiency involve distinct issues with your vision and eye health, progressing from difficulty seeing in low light to overall dryness and damage.

Quick Summary

The earliest indicators of vitamin A deficiency are night blindness (difficulty seeing in dim light) and dry eyes (xerophthalmia). This progressive condition affects the retina and the moisture-producing membranes of the eye, which can worsen over time without proper treatment. While these visual symptoms are the most common initial signs, the deficiency can also manifest as skin dryness and a compromised immune system.

Key Points

Night Blindness: One of the earliest indicators is nyctalopia, or the inability to see well in dim light, due to impaired rhodopsin production in the retina.
Dry Eyes (Xerophthalmia): The second primary sign is the progressive dryness of the eyes, starting with the conjunctiva and potentially leading to corneal ulcers and blindness if left untreated.
Skin Dryness: Vitamin A deficiency also affects skin health, causing it to become dry, scaly, and prone to inflammation.
Impaired Immunity: A weaker immune response is another sign, as vitamin A is crucial for fighting infections.
Dietary Prevention: Prevention relies on consuming foods rich in both preformed vitamin A (e.g., liver, eggs) and provitamin A carotenoids (e.g., sweet potatoes, carrots).
Irreversible Damage: While early symptoms are reversible with treatment, advanced corneal damage can result in permanent blindness.

The Initial Impact: Night Blindness

One of the most characteristic and earliest symptoms of vitamin A deficiency is night blindness, or nyctalopia. This condition impairs a person's ability to see clearly in low-light conditions, such as at dusk or in dimly lit rooms. The reason for this lies in the vitamin's crucial role in producing rhodopsin, a pigment in the eye's retina that is highly sensitive to light.

How it Works: Your eyes' rod cells rely on vitamin A to produce rhodopsin. When vitamin A levels are insufficient, the regeneration of this pigment slows down, and the rod cells can't function effectively in the dark.
Experience: Individuals with nyctalopia may notice they have trouble navigating dark spaces or driving at night, even though their vision is normal in well-lit environments.
Reversibility: If caught early, this particular symptom is often reversible with vitamin A supplementation.

The Second Sign: Dry Eyes (Xerophthalmia)

As the deficiency progresses, the next significant sign to appear is xerophthalmia, a term for a spectrum of dry eye conditions. The conjunctiva (the membrane covering the whites of your eyes) and the cornea begin to dry out due to the body's inability to produce adequate moisture.

Progressive Symptoms: The dryness starts in the conjunctiva (conjunctival xerosis), giving the eye a dull, wrinkled appearance. This can lead to the formation of Bitot's spots—foamy, grayish patches on the conjunctiva.
Corneal Damage: If left untreated, the dryness can affect the cornea, potentially leading to corneal ulcers and softening (keratomalacia). This is a severe stage that can result in irreversible blindness.
Tear Production: The lack of vitamin A interferes with the normal function of tear ducts, further exacerbating the problem of dry, irritated eyes.

Other Early Manifestations of Deficiency

While night blindness and xerophthalmia are the most prominent initial signs, a lack of vitamin A can also show up in other areas of the body, particularly the skin. Vitamin A is vital for the creation and repair of skin cells. Consequently, a deficiency can disrupt this process, leading to a condition called hyperkeratosis.

Dry, Flaky Skin: The skin can become dry, scaly, and thick, with rough patches forming over time.
Increased Infections: Vitamin A is critical for a healthy immune system. Its deficiency weakens immune function, making individuals more susceptible to respiratory and other infections.
Impaired Growth: In children, a vitamin A deficiency can lead to stunted growth and development.

Early Signs vs. Advanced Symptoms


Feature	Early Signs	Advanced Symptoms
Symptom Duration	Appears shortly after vitamin A stores are depleted.	Develops over time if the deficiency is not addressed.
Effect on Vision	Night blindness (difficulty seeing in dim light).	Complete blindness, corneal ulcers, and permanent eye damage.
Physical Manifestations	Dry eyes (conjunctival xerosis) and dry, flaky skin.	Foamy Bitot's spots on the eyes, severe skin keratinization, and heightened infection risk.
Reversibility	Symptoms like night blindness are often reversible with supplementation.	Severe corneal damage is often irreversible.

Sources of Vitamin A and Prevention

To prevent a vitamin A deficiency, a balanced diet rich in this nutrient is essential. Vitamin A comes in two main forms:

Preformed Vitamin A (Retinol): Found in animal products, including liver, eggs, and dairy products. It is ready for the body to use directly.
Provitamin A Carotenoids: Found in plant-based foods, such as beta-carotene, which the body converts into vitamin A. Good sources include sweet potatoes, carrots, spinach, and other dark leafy greens.

Regular consumption of these foods can help maintain adequate vitamin A levels, especially for at-risk populations like children and pregnant women. Public health initiatives often involve supplementation programs in areas where deficiency is widespread.

Conclusion: The Critical Nature of Early Detection

In conclusion, the first two signs of vitamin A deficiency are night blindness and dry eyes (xerophthalmia), which progress if untreated. Because this is a gradual but progressive condition, recognizing these early indicators is vital for preventing permanent and severe health complications. By understanding the importance of vitamin A for vision and overall health and ensuring adequate intake through diet or supplementation, individuals can protect themselves from this preventable deficiency. Early detection and intervention can halt the progression of symptoms and reverse many of the initial effects, reinforcing the need for awareness and good nutritional practices.

For more in-depth medical insights, consult the Merck Manuals on Vitamin A Deficiency.

Frequently Asked Questions

The very first clinical sign of a vitamin A deficiency is night blindness (nyctalopia), which is characterized by the inability to see clearly in dim light or at night.

Xerophthalmia is a progressive eye disease caused by vitamin A deficiency that leads to severe dryness of the tear ducts and eye. The lack of vitamin A hinders the body's ability to produce the moisture needed to keep the eyes properly lubricated.

Yes, dry, scaly, and rough skin is another sign of a vitamin A deficiency. Vitamin A is essential for the creation and repair of skin cells, and a lack of it can disrupt this process.

Good sources include both animal products with preformed vitamin A (liver, fish, eggs, dairy) and plant-based foods with provitamin A carotenoids (sweet potatoes, carrots, spinach, kale).

Night blindness caused by a vitamin A deficiency is often treated with high-dose vitamin A supplements, which can help reverse the symptom by restoring the production of light-sensitive pigments in the retina.

Vitamin A deficiency is relatively rare in developed countries like the U.S. but remains a major public health problem in many developing nations, primarily affecting children and pregnant women.

If a vitamin A deficiency progresses to the point of corneal ulceration and scarring (keratomalacia), the resulting vision loss can be permanent and cannot be reversed.