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Data

Share of children who have vitamin A deficiency

About this data

Source
WHO (2009) – processed by Our World in Data
Last updated
July 23, 2017
Date range
2005–2005
Unit
%

Sources and processing

This data is based on the following sources

WHO – Global prevalence of vitamin A deficiency in populations at risk 1995–2005

Data on vitamin-A deficiency is based on the reported prevalence of risk by the World Health Organization, which has collated national and household level survey data on indicators extending the period 1995-2005. Note that data on vitamin-A deficiency is typically not measured on an annual basis, therefore the year of measurement will vary by country, but lie within the period 1995-2005.

All countries with a GDP per capita ≥US$15,000 were assumed by the WHO to be free from vitamin-A deficiency of a public health significance and were therefore excluded. None of these 37 countries had retinol or night blindness data reported for either preschool-age children or pregnant women.

Two sets of indicators of VAD are commonly used for population surveys: clinically assessed eye signs and biochemically determined concentrations of retinol in plasma or serum. The incidence of night blindness in individuals indicates moderate-to-severe systemic VAD. VAD can also be identified when serum retinol concentrations fall below below a cut-off value of 0.70 µmol/l.

Vitamin A deficiency (VAD) is a major nutritional concern in poor societies, especially in lower income countries. Its presence as a public health problem is assessed by measuring the prevalence of deficiency in a population, represented by specific biochemical and clinical indicators of status. The main underlying cause of VAD as a public health problem is a diet that is chronically insufficient in vitamin A that can lead to lower body stores and fail to meet physiologic needs (e.g. support tissue growth, normal metabolism, resistance to infection). Deficiency of sufficient duration or severity can lead to disorders that are common in vitamin A deficient populations such as xerophthalmia (xeros = dryness; -ophthalmia = pertaining to the eye), the leading cause of preventable childhood blindness, anaemia, and weakened host resistance to infection, which can increase the severity of infectious diseases and risk of death.

Retrieved on
July 23, 2017
Retrieved from
http://apps.who.int/iris/bitstream/10665/44110/1/9789241598019_eng.pdf
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
WHO. Global prevalence of vitamin A deficiency in populations at risk 1995–2005. WHO Global Database on Vitamin A Deficiency. Geneva, World Health Organization, 2009.

Data on vitamin-A deficiency is based on the reported prevalence of risk by the World Health Organization, which has collated national and household level survey data on indicators extending the period 1995-2005. Note that data on vitamin-A deficiency is typically not measured on an annual basis, therefore the year of measurement will vary by country, but lie within the period 1995-2005.

All countries with a GDP per capita ≥US$15,000 were assumed by the WHO to be free from vitamin-A deficiency of a public health significance and were therefore excluded. None of these 37 countries had retinol or night blindness data reported for either preschool-age children or pregnant women.

Two sets of indicators of VAD are commonly used for population surveys: clinically assessed eye signs and biochemically determined concentrations of retinol in plasma or serum. The incidence of night blindness in individuals indicates moderate-to-severe systemic VAD. VAD can also be identified when serum retinol concentrations fall below below a cut-off value of 0.70 µmol/l.

Vitamin A deficiency (VAD) is a major nutritional concern in poor societies, especially in lower income countries. Its presence as a public health problem is assessed by measuring the prevalence of deficiency in a population, represented by specific biochemical and clinical indicators of status. The main underlying cause of VAD as a public health problem is a diet that is chronically insufficient in vitamin A that can lead to lower body stores and fail to meet physiologic needs (e.g. support tissue growth, normal metabolism, resistance to infection). Deficiency of sufficient duration or severity can lead to disorders that are common in vitamin A deficient populations such as xerophthalmia (xeros = dryness; -ophthalmia = pertaining to the eye), the leading cause of preventable childhood blindness, anaemia, and weakened host resistance to infection, which can increase the severity of infectious diseases and risk of death.

Retrieved on
July 23, 2017
Retrieved from
http://apps.who.int/iris/bitstream/10665/44110/1/9789241598019_eng.pdf
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
WHO. Global prevalence of vitamin A deficiency in populations at risk 1995–2005. WHO Global Database on Vitamin A Deficiency. Geneva, World Health Organization, 2009.

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“Data Page: Share of children who have vitamin A deficiency”. Our World in Data (2026). Data adapted from WHO. Retrieved from https://archive.ourworldindata.org/20260511-092124/grapher/prevalence-of-vitamin-a-deficiency-in-children.html [online resource] (archived on May 11, 2026).

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WHO (2009) – processed by Our World in Data

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WHO (2009) – processed by Our World in Data. “Share of children who have vitamin A deficiency” [dataset]. WHO, “Global prevalence of vitamin A deficiency in populations at risk 1995–2005” [original data]. Retrieved May 11, 2026 from https://archive.ourworldindata.org/20260511-092124/grapher/prevalence-of-vitamin-a-deficiency-in-children.html (archived on May 11, 2026).

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