Which countries have vitamin A deficiency?

January 1, 2026 •

4 min read

According to the World Health Organization (WHO), vitamin A deficiency (VAD) is a public health problem in more than half of all countries, with the highest prevalence in regions like Africa and South-East Asia. A significant portion of young children and pregnant women in low-income settings are particularly vulnerable to this widespread nutritional issue.

Quick Summary

Vitamin A deficiency disproportionately affects low-income countries, particularly in Sub-Saharan Africa and South Asia, due to poor diet and high infection rates. Vulnerable populations, including young children and pregnant women, face severe health consequences like blindness and increased risk of disease. Global interventions are working to address this critical public health concern.

Key Points

Prevalence Hotspots: The highest rates of vitamin A deficiency are found in Sub-Saharan Africa and South Asia, impacting large populations in these low-income regions.
Vulnerable Groups: Young children and pregnant women are the most severely affected by vitamin A deficiency, facing increased risk of illness, blindness, and mortality.
Contributing Factors: The deficiency is driven by poor dietary intake, high rates of infectious diseases like measles, and underlying socioeconomic factors such as poverty.
Key Interventions: Strategies to combat VAD include high-dose supplementation programs, food fortification, and promoting dietary diversification to improve nutrient intake.
Public Health Problem: The World Health Organization (WHO) classifies VAD as a significant public health problem in over half the world's countries, requiring continuous monitoring and targeted interventions.

Mapping the Global Burden of Vitamin A Deficiency

Vitamin A deficiency (VAD), while rare in high-income nations, persists as a critical public health issue across many low- and middle-income countries. This micronutrient shortage results from inadequate dietary intake and is worsened by high rates of infection, especially among vulnerable populations such as young children and pregnant women. Understanding the geographical distribution of VAD is essential for implementing targeted, effective public health interventions.

High-Prevalence Regions: Sub-Saharan Africa and South Asia

The highest rates of VAD are consistently found in two major global regions: Sub-Saharan Africa and South Asia. These areas face significant socioeconomic challenges that contribute to food insecurity and limited access to diverse, nutrient-rich diets.

Sub-Saharan Africa: Data consistently shows this region with the highest rates of VAD. In 2013, the WHO reported that 48% of preschool-age children in Sub-Saharan Africa were affected by VAD. Countries with particularly high age-standardized mortality and morbidity rates include Somalia, Niger, Chad, and the Central African Republic. Despite global efforts, significant improvements in VAD morbidities have not been universally realized across the region, highlighting the ongoing severity of the problem.
South Asia: This region also has a major burden, with the WHO reporting that 44% of preschool-age children were affected in 2013. Poorer settings with economic deprivation are most impacted. Countries such as India, Bangladesh, and Pakistan show high rates of VAD, affecting millions of children and pregnant women. The issue is linked to reliance on plant-based diets with poor vitamin A bioavailability and insufficient governmental support for intervention programs in some areas.

Other Affected Regions and Vulnerable Populations

While Sub-Saharan Africa and South Asia bear the greatest burden, VAD is a concern in other parts of the world, particularly within specific populations.

Eastern Mediterranean Region (EMR): Recent studies indicate a potentially increasing burden of VAD in this region, with one report suggesting a higher prevalence among children aged 0-5 compared to South-East Asia.
Latin America and the Caribbean: While largely controlled in many areas, countries like Haiti have a high incidence of VAD comparable to some Asian nations.
Displaced and Refugee Populations: Severe VAD is frequently observed in refugee settlements and among displaced populations, where living conditions and access to nutritious food are extremely limited.

Contributing Factors to Vitamin A Deficiency

Several interconnected factors drive VAD prevalence in these high-risk countries:

Poor Dietary Intake: Diets lacking sources of both preformed vitamin A (from animal products) and provitamin A carotenoids (from fruits and vegetables) are the primary cause. In many low-income areas, access to animal products is limited by cost.
High Rates of Infection: Frequent infections, especially measles and diarrheal diseases, can drastically lower the body's vitamin A levels. These infections compromise intestinal absorption and increase vitamin A excretion, creating a vicious cycle.
Socioeconomic Barriers: Poverty and associated food insecurity are significant drivers. Lower-income populations are less able to afford vitamin A-rich foods, making them especially vulnerable.
Deficient Breastmilk: In settings where maternal nutrition is poor, breast milk may have insufficient vitamin A concentration, which can fail to build up vital liver reserves in infants.
Zinc Deficiency: A concurrent deficiency of zinc, a micronutrient crucial for vitamin A absorption and transport, can also exacerbate VAD.

Global Interventions and Progress

Public health interventions have been crucial in combating VAD, though challenges remain.

Vitamin A Supplementation vs. Dietary Approaches


Intervention Strategy	Description	Efficacy and Challenges
High-Dose Supplementation	Providing high-dose vitamin A capsules to children aged 6-59 months, typically every six months.	Highly effective in reducing childhood mortality and blindness. Challenges include ensuring wide coverage, funding, and logistical issues.
Dietary Diversification	Promoting the consumption of a wider variety of vitamin A-rich foods, including animal products, fruits, and vegetables.	Sustainable long-term solution. Can be slow to implement and faces barriers like cost and dietary habits.
Food Fortification	Adding vitamin A to staple foods like flour, sugar, or cooking oil.	A large-scale, cost-effective strategy. Requires consistent manufacturing standards and public health policy support.

Conclusion

While high-income countries rarely face widespread issues with vitamin A deficiency, it remains a significant and serious public health problem in many low- and middle-income countries. The greatest burden is concentrated in Sub-Saharan Africa and South Asia, where inadequate diet, poverty, and high rates of infection create a perfect storm of risk. Although interventions like supplementation have proven effective in reducing mortality, persistent gaps remain in many regions. A multifaceted approach combining supplementation, dietary improvement, and addressing underlying socioeconomic issues is essential to continue making progress toward eliminating this preventable cause of childhood blindness and increased mortality.

The WHO's Role in Addressing VAD

The World Health Organization (WHO) plays a critical role in monitoring and guiding the global response to VAD. Its activities include:

Defining and tracking: The WHO defines clinical and subclinical VAD and establishes cut-off values for public health significance, such as serum or plasma retinol levels.
Developing guidelines: The organization publishes guidelines for vitamin A supplementation programs, particularly targeting vulnerable groups like children and pregnant women.
Data collection: The Vitamin and Mineral Nutrition Information System (VMNIS) database is used to collect and disseminate prevalence data to track progress.

Here is a useful resource on global vitamin A deficiency statistics from UNICEF.

Frequently Asked Questions

Vitamin A deficiency (VAD) is a condition resulting from an inadequate intake of vitamin A, a vital nutrient for vision, immune function, and cell growth. It is most prevalent in developing countries.

The regions with the highest prevalence of vitamin A deficiency are Sub-Saharan Africa and South Asia, where it is classified as a significant public health problem.

Young children and pregnant women in low-income countries are particularly vulnerable to vitamin A deficiency, often experiencing the most severe health consequences.

VAD can lead to night blindness, xerophthalmia (dry eyes), increased susceptibility to infections like measles and diarrhea, slowed growth, and increased risk of mortality.

No, vitamin A deficiency is rarely seen in developed countries due to readily available nutrient-rich foods. Cases that do occur are typically linked to malabsorption issues, not diet.

Prevention and treatment strategies include high-dose vitamin A supplementation for at-risk children and pregnant women, food fortification, and programs promoting dietary diversification to include more vitamin A-rich foods.

Diet is the main factor in VAD. Many affected populations rely on diets low in both animal-based sources (retinol) and plant-based sources (beta-carotene), compounded by poverty that limits access to diverse foods.

Infections, particularly measles and diarrheal illnesses, can exacerbate VAD by interfering with the body's absorption and storage of vitamin A, often leading to a rapid drop in vitamin A levels.