What are the symptoms of a vitamin A deficiency?

Vitamin A is a fat-soluble nutrient essential for vision, immune function, and skin health. Deficiency can present with a spectrum of signs that range from early functional changes to irreversible tissue damage. Early recognition is important because many symptoms respond well to nutritional correction, while advanced stages may cause permanent harm.

Common early signs

The earliest and most specific symptom is night blindness (nyctalopia), a reduced ability to see in low light due to impaired rhodopsin regeneration in retinal rod cells. Patients often report difficulty driving at night or taking longer to adjust when moving from bright to dim environments. Mild ocular dryness and conjunctival irritation may also appear as the eyes lose some protective mucosal support.

Skin and mucosal indicators

Vitamin A helps regulate skin cell differentiation and maintain mucous membranes. Deficiency commonly causes dry, rough, or flaky skin and can progress to follicular hyperkeratosis—small, rough bumps around hair follicles. Mucous membranes in the respiratory and gastrointestinal tracts may become drier and more vulnerable to infection, contributing to recurrent respiratory or gastrointestinal illnesses.

Immune and healing effects

Because vitamin A supports epithelial barriers and immune cell function, inadequate levels are associated with increased susceptibility to infections and slower wound healing. Children and older adults with low vitamin A status may experience more frequent respiratory infections, diarrheal episodes, and prolonged recovery times.

Progressive visual impairment

If deficiency persists, structural eye changes may develop including xerophthalmia (drying of the conjunctiva and cornea), corneal ulceration, and keratomalacia. These advanced changes can lead to irreversible visual loss. Blurred vision, light sensitivity, and a foreign-body sensation can precede severe corneal damage.

Who is at risk?

Populations at higher risk include young children, pregnant and lactating women, people with fat-malabsorption disorders (such as celiac disease or cystic fibrosis), and individuals consuming highly restrictive diets. Public health programs in some regions use targeted supplementation to reduce deficiency-related morbidity.

Assessment and management

Diagnosis is based on clinical signs and dietary assessment, and can be supported by biochemical measures of retinol when available. Management focuses on correcting intake through diet and, when needed, carefully dosed supplements. Guidance on supplement dosing and safety, including considerations for vulnerable groups, is available in resources about how to determine the right dosage of nutritional supplements.

For a concise overview of presenting features, see this summary on symptoms of vitamin A deficiency. Comparative nutrient considerations, such as overlapping signs with vitamin D deficiency, are discussed in literature on symptoms of low vitamin D and in a related Telegraph summary of vitamin D deficiency.

Practical notes

Food sources of preformed vitamin A (retinol) include liver, dairy, and eggs; provitamin A carotenoids are abundant in orange and dark leafy vegetables. While food-first approaches are preferred, supplements can correct deficiencies when dietary measures or absorption are inadequate. Because excess preformed vitamin A can be toxic, supplementation should follow professional recommendations.