Vitamin A deficiency is rare in the US but remains the world's leading preventable cause of childhood blindness in developing countries. WHO estimates 250,000-500,000 children become blind from vitamin A deficiency each year, with about half dying within 12 months. The first sign is usually night blindness; severe deficiency causes irreversible eye damage.
Common symptoms
Night blindness (nyctalopia) — difficulty seeing in low light
Dry eyes, reduced tear production (xerophthalmia)
Bitot spots — foamy, white patches on the whites of the eyes
Corneal drying, ulceration, or scarring (advanced)
Permanent blindness (severe, untreated cases)
Frequent infections, especially respiratory and diarrheal
Dry, rough skin or follicular hyperkeratosis
Slow growth in children
Anemia
At-risk groups
Children in low-income countries with limited dietary variety
Pregnant women in developing countries (maternal night blindness affects 5-10% in some regions)
Premature infants (limited liver stores at birth)
People with fat malabsorption (cystic fibrosis, celiac disease, pancreatic insufficiency, biliary disease)
People who've had bariatric surgery, especially biliopancreatic diversion
People with chronic alcohol use disorder
People with very limited diets or anorexia
When to see a doctorDifficulty seeing at night or in dim light — especially after gradually worsening over weeks — should be evaluated promptly, particularly in pregnant women or anyone with fat malabsorption. Important: vitamin A is fat-soluble and accumulates in the body. Do NOT take high-dose vitamin A (>10,000 IU/day) without medical guidance — toxicity causes liver damage, and excess during pregnancy causes severe birth defects.