What Percentage of People Are Deficient in Vitamin A? Global and Regional Stats

November 18, 2025 •

4 min read

According to a 2019 study, an estimated 14.73% of children and adolescents in low- and middle-income countries were deficient in vitamin A, with the prevalence being significantly higher in younger age groups. This nutrient deficiency is a major global public health concern, with vast disparities based on geography and socioeconomic factors.

Quick Summary

The prevalence of vitamin A deficiency varies dramatically worldwide, primarily affecting vulnerable populations in low-income regions due to inadequate dietary intake and high rates of infection.

Key Points

Global Disparity: The percentage of people with vitamin A deficiency is very low in developed countries but significantly high in low- and middle-income countries.
Vulnerable Groups: Infants, preschool-aged children, and pregnant or breastfeeding women are the most susceptible to vitamin A deficiency, especially in resource-poor regions.
Leading Cause of Blindness: Globally, vitamin A deficiency is the most important cause of preventable childhood blindness, affecting hundreds of thousands of children annually.
Causes: Insufficient dietary intake, chronic infections like measles and diarrhea, and malabsorption conditions such as celiac disease are major contributors to vitamin A deficiency.
Impact: Beyond visual problems like night blindness and xerophthalmia, VAD severely weakens the immune system, increasing vulnerability to infections and contributing to child mortality.
Prevention: Public health strategies like large-scale vitamin A supplementation programs and food fortification have been effective in reducing deficiency in endemic areas.

Global Prevalence and Stark Regional Differences

Vitamin A deficiency (VAD) is a serious yet often overlooked public health problem, with its prevalence tied closely to a region's economic status. The statistics paint a clear picture of a global divide, with low- and middle-income countries (LMICs) bearing the overwhelming burden, while VAD remains rare in developed, nutrient-rich nations. For instance, a 2019 study found that approximately 14.73% of children and adolescents across 165 LMICs were deficient in vitamin A, affecting over 333 million young people. This contrasts sharply with countries like the United States, where prevalence is less than 1% of the general population.

Within LMICs, the prevalence is not uniform. The highest rates are seen in low Socio-Demographic Index (SDI) regions, where nearly 30% of the pediatric population was deficient in 2019, almost five times higher than in high-middle SDI regions. In contrast, a 2015 study reported that vitamin A deficiency rates were highest in sub-Saharan Africa (48%) and South Asia (44%) among children. These figures demonstrate that the risk for vitamin A deficiency is not evenly distributed across the globe but is concentrated in areas with limited access to diverse, nutrient-rich foods.

Causes of Vitamin A Deficiency

Several factors contribute to vitamin A deficiency, ranging from dietary issues to physiological and environmental factors. A primary cause is insufficient dietary intake, where staple foods like rice (which lacks beta-carotene) form the basis of the diet in many endemic regions. The body needs either preformed vitamin A from animal sources or provitamin A carotenoids from plants to function properly.

Dietary Factors

Limited access to nutrient-rich foods: In many low-income settings, economic hardship prevents access to a varied diet that includes animal products like liver, eggs, and dairy, as well as orange and dark green vegetables.
Poor absorption of carotenoids: The body’s absorption of plant-based carotenoids is less efficient than that of preformed vitamin A and requires dietary fat. A diet lacking in fat can hinder the conversion of carotenoids to vitamin A.

Medical and Physiological Factors

Infections: Chronic or recurring infections, particularly diarrheal diseases and measles, significantly increase the body's demand for vitamin A and can deplete existing stores.
Malabsorption issues: Conditions such as cystic fibrosis, celiac disease, chronic pancreatitis, and inflammatory bowel disease can all interfere with the body's ability to absorb fat-soluble vitamins, including vitamin A.
Liver disorders: Since the liver stores most of the body's vitamin A, any liver disease can impede the proper storage and release of the vitamin.
Increased requirements during pregnancy and lactation: Women of childbearing age have higher vitamin A needs. In deficient mothers, newborns often start life with low reserves and receive insufficient vitamin A through breastmilk.

Symptoms and Complications

Early detection and treatment of VAD are crucial to prevent severe complications, many of which affect vision and immune function.

Visual Symptoms:

Night Blindness (Nyctalopia): This is one of the earliest signs, making it difficult to see in dim light.
Xerophthalmia: A progressive dryness of the conjunctiva and cornea, which can worsen to include corneal ulcers and scarring.
Bitot’s Spots: The appearance of foamy, whitish patches on the whites of the eyes.
Keratomalacia: The softening and breakdown of the cornea, which can lead to permanent blindness.

Non-Visual Symptoms:

Compromised Immune System: A weakened immune response leads to increased susceptibility to infectious diseases, especially respiratory and gastrointestinal infections.
Stunted Growth: Children with VAD often experience delayed growth and development.
Dry Skin: A lack of vitamin A can cause skin dryness, flakiness, and the formation of keratinized plaques.

Global vs. Developed Country Prevalence


Characteristic	Developed Countries (e.g., USA)	Low- and Middle-Income Countries (LMICs)
Prevalence	Very low (often <1%)	High, especially among children (e.g., 14.73% of children and adolescents in 2019)
Primary Cause	Usually malabsorption due to medical conditions (e.g., cystic fibrosis)	Insufficient dietary intake exacerbated by infections and poverty
Vulnerable Groups	Individuals with chronic health issues, some ethnic groups, and those with poor diet	Infants, preschool-aged children, and pregnant or lactating women
Interventions	Targeted care for at-risk individuals with health conditions	Widespread food fortification, supplementation programs, and public health initiatives

The Role of Public Health Interventions

Since the late 20th century, global efforts have been underway to combat VAD in endemic regions. Organizations like the World Health Organization (WHO) and UNICEF have implemented large-scale programs, such as periodic vitamin A supplementation campaigns for children. These interventions have been successful in reducing the mortality rates associated with VAD in many areas.

Other strategies include food fortification, where staples like cooking oil, sugar, and flour are enriched with vitamin A. Nutritional education and promoting dietary diversity are also crucial long-term solutions, encouraging the consumption of local, vitamin A-rich foods.

Conclusion

Vitamin A deficiency remains a significant public health issue, primarily impacting vulnerable populations in low-income regions of Africa and Asia. While a very small percentage of the population is affected in developed nations, the global figures are substantial, with a 2019 study finding a 14.73% prevalence among children and adolescents in LMICs. The causes are multi-faceted, stemming from inadequate diet and worsened by high rates of infection. Continuous public health interventions, including supplementation, food fortification, and nutritional education, are essential to reduce the burden of this preventable condition and its devastating consequences, particularly for young children.

Learn more about how vitamin A impacts global health from the World Health Organization: https://www.who.int/data/nutrition/nlis/info/vitamin-a-deficiency

Frequently Asked Questions

One of the earliest and most notable signs of vitamin A deficiency is night blindness (nyctalopia), which is difficulty seeing in dim light.

In developing countries, the primary cause is an insufficient dietary intake of vitamin A, often due to a lack of access to diverse, nutrient-rich foods.

While rare in developed countries, vitamin A deficiency can occur in individuals with certain medical conditions that affect fat absorption, such as cystic fibrosis, celiac disease, or chronic liver disease.

You can increase your vitamin A intake by eating more animal products like liver, eggs, and fortified milk, or plant sources such as carrots, sweet potatoes, dark leafy greens, and mangoes.

In regions where VAD is a public health concern, supplementation programs are vital. In developed nations, supplements are typically only necessary for individuals with absorption issues or specific medical advice, as excessive intake can be toxic.

Yes, pregnant and breastfeeding women have increased vitamin A requirements. A deficiency during this period can lead to night blindness in the mother and low vitamin A reserves in the newborn.

Preformed vitamin A, or retinol, is found in animal products, while provitamin A carotenoids, like beta-carotene, come from plant sources and are converted into active vitamin A by the body.