Night Blindness and Xerophthalmia: Vitamin A Deficiency Worldwide and in High-Income Countries
What WHO and health services say about night blindness and xerophthalmia, how vitamin A deficiency differs worldwide and in high-income countries, and why an eye exam comes first.
Content last updated . This page has not been medically reviewed.
See an eye doctor first
Night blindness means poor vision at night or in dim light. MedlinePlus lists vitamin A deficiency as only one of several treatable causes, alongside cataracts, nearsightedness and some medicines, and says a complete eye exam is important to find the cause. [1] Do not assume that trouble seeing in the dark is a vitamin problem, and do not start vitamin A on your own. Too much vitamin A can be harmful, and large doses in pregnancy can cause birth defects. [2]Key terms
- Vitamin A deficiency is defined by WHO as an intake that is inadequate to satisfy physiological needs. [3]
- Xerophthalmia is, in WHO's wording, the clinical spectrum of eye effects of vitamin A deficiency, from milder stages such as night blindness and Bitot spots to blinding stages such as corneal xerosis, ulceration and necrosis (keratomalacia). [3]
- Night blindness is one of the first signs. MedlinePlus describes it as reversible, whereas the corneal damage of xerophthalmia is not reversible. [2]
Worldwide: a public health problem
WHO says vitamin A deficiency is common in developing countries but rarely seen in developed countries, and is a public health problem in more than half of all countries, especially in Africa and South-East Asia. The most severe effects are in young children and pregnant women in low-income countries. [3] WHO calls it the world's leading preventable cause of childhood blindness and links it to serious harm from common childhood infections. [3]| Question | What the source found | Strength of evidence |
|---|---|---|
| Is vitamin A deficiency a cause of blindness in children? | WHO describes it as the leading preventable cause of childhood blindness. [3] | Established nutritional role / deficiency treatment |
| Is night blindness common in pregnancy? | WHO says it is common during pregnancy in developing countries. [3] | Population data, low-income settings |
| Can a blood retinol test diagnose it in one person? | WHO says serum retinol is best used to assess subclinical deficiency in a population, not in an individual. [3] | Test limit |
In high-income countries
MedlinePlus says vitamin A deficiency is very rare in the United States. [2] When it occurs, the published reports we found point to poor absorption of fat-soluble vitamins rather than to diet alone:- A Swiss hospital case series (2012 to 2022) found five people with deficiency-related retinopathy after medical interventions that cause malabsorption: three had bariatric surgery, one had a small bowel resection and took octreotide, and one had cystic fibrosis. The authors advise measuring vitamin A levels in cases of night blindness. [4]
- A US case report described deficiency with night blindness in a person with chronic pancreatitis, and a second reported it after duodenal switch surgery. [5] [6]
These are case reports and a small series, so they show that it can happen, not how often. Proper evidence not found for how common deficiency is in the general population of high-income countries: we searched PubMed on 2026-10-23 for reviews and did not find one we could read. For who is at risk in general see Who is at risk of vitamin deficiency?, Vitamins after bariatric surgery and Malabsorption, celiac disease, IBD and vitamin deficiency.
Food sources and intake reference
MedlinePlus lists preformed vitamin A in meat, fish, poultry and dairy, and provitamin A (such as beta-carotene) in fruits and vegetables. [2] The NHS says adults aged 19 to 64 need 700 micrograms (µg) of retinol equivalents a day for men and 600 µg for women, and that you should be able to get this from a varied diet. [7] That is a UK figure (reviewed 2020), not a universal one. See Foods high in vitamin A and the full profile at Vitamin A.Frequently asked questions
Does night blindness mean I lack vitamin A?
Not necessarily. MedlinePlus lists cataracts, nearsightedness and some medicines among causes, and says vitamin A deficiency is a rare cause. [1]
What is xerophthalmia?
WHO describes it as the range of eye effects of vitamin A deficiency, from night blindness to damage of the cornea. [3]
Can vitamin A deficiency happen in rich countries?
It is rare, but reports describe it after bariatric or bowel surgery or in cystic fibrosis. [4]
Can a blood test confirm vitamin A deficiency?
WHO says serum retinol is best used for populations rather than individuals, because between very low and very high levels it is tightly regulated. [3]
Is it safe to take extra vitamin A for my eyes?
Not without advice. MedlinePlus warns that too much vitamin A can build up and cause serious health problems. [2]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
How to read the evidence labels
Labels used on this page: established nutritional role / deficiency treatment, insufficient evidence and Proper evidence not found.
Safety: both too little and too much matter
- Pregnancy: MedlinePlus says large doses of vitamin A in pregnant women can cause birth defects. [2] The NHS says to avoid liver and liver products in pregnancy. [7] See Vitamin A excess, pregnancy and retinoid medicines.
- Children: MedlinePlus says babies and children are more sensitive to vitamin A, and swallowing products that contain it, such as retinol skin cream, can cause poisoning. [2] In the US, Poison Help is 1-800-222-1222. See Vitamin overdose in children.
- Older adults and bones: the NHS cites research suggesting long-term intake above an average of 1.5 mg (1,500 µg) a day may affect bones, and advises care with liver and supplements. [7]
- Smokers: MedlinePlus says beta-carotene supplements may raise cancer risk in current and former smokers. [2]
- Measles: MedlinePlus says it is not recommended to take vitamin A to prevent measles. [2]
- Kidney and liver disease, surgery, medicines: the pages we read give no specific advice, so ask your care team. See Medication interactions and Quality testing and certifications.
Where deficiency is confirmed, MedlinePlus says vitamin A supplements may be helpful and to ask your provider how much to take, because it is possible to take too much. [1] A clinician or pharmacist decides the right amount for a person.
References
- MedlinePlus Medical Encyclopedia (US National Library of Medicine). Vision - night blindness. Review date 8/5/2024. Read 2026-10-23.
- MedlinePlus Medical Encyclopedia (US National Library of Medicine). Vitamin A. Review date 1/21/2025. Read 2026-10-23.
- World Health Organization, Nutrition Landscape Information System. Vitamin A deficiency. No review date shown on the page. Read 2026-10-23.
- Gunzinger JM, et al. Vitamin A deficiency retinopathy related to medical interventions in a Swiss cohort: a case series. Swiss Med Wkly. 2023;153:40097. PubMed 37921090 (abstract). Read 2026-10-23.
- Lee A, et al. Case report: vitamin A deficiency and nyctalopia in a patient with chronic pancreatitis. Optom Vis Sci. 2019;96(6):453-458. PubMed 31107845 (abstract). Read 2026-10-23.
- Lima de Carvalho JR Jr, Tsang SH, Sparrow JR. Vitamin A deficiency monitored by quantitative short wavelength fundus autofluorescence in a case of bariatric surgery. Retin Cases Brief Rep. 2022;16(2):218-221. PubMed 31599792 (abstract). Read 2026-10-23.
- NHS (UK). Vitamin A. Page last reviewed 3 August 2020. Read 2026-10-23.