What population groups are at highest risk of vitamin A deficiency?

October 16, 2025 •

4 min read

Globally, an estimated 190 million preschool-age children suffer from vitamin A deficiency (VAD), making it one of the most prevalent and serious micronutrient deficiencies worldwide. This deficiency is a significant public health problem, particularly affecting certain vulnerable populations due to a combination of inadequate dietary intake and increased physiological needs.

Quick Summary

This article explores the specific demographics and medical conditions that put certain groups at heightened risk for vitamin A deficiency. It details the reasons behind their vulnerability, such as poor diet, heightened physiological demands, and malabsorption issues, and outlines the serious health consequences and preventive measures.

Key Points

Young Children: Children aged 6-59 months, particularly in developing countries, are at the highest risk due to rapid growth and limited vitamin A intake.
Pregnant and Lactating Women: Increased physiological demands during pregnancy and breastfeeding, especially in low-income regions, put these women at risk of deficiency.
Fat Malabsorption Disorders: Conditions like cystic fibrosis, chronic pancreatitis, and certain surgeries (e.g., bariatric surgery) prevent proper vitamin A absorption.
Infectious Diseases: Frequent infections like measles and diarrhea, common in low-income countries, can deplete the body's vitamin A stores.
Socioeconomic Factors: Lack of dietary diversity and poverty are significant drivers of VAD, particularly in sub-Saharan Africa and Southeast Asia.
Preterm Infants: Premature babies are born with lower vitamin A reserves and have immature digestive systems, increasing their vulnerability.
Alcohol Use Disorder: Chronic alcohol abuse impairs the liver's ability to store and metabolize vitamin A, leading to deficiency.
Vegans: Individuals on strict plant-based diets can be at risk if they do not consume enough provitamin A sources, which are less bioavailable than preformed vitamin A.

Vulnerable populations in developing countries

Vitamin A deficiency (VAD) remains a severe public health issue in many low- and middle-income countries, predominantly in sub-Saharan Africa and South and Southeast Asia. In these regions, limited access to diverse, nutrient-rich foods is a primary driver of deficiency, exacerbated by infectious diseases that further deplete the body's vitamin A stores.

Young children (6 months to 5 years)

Young children are disproportionately affected by VAD due to their rapid growth, which increases their demand for this essential nutrient. Infants are born with minimal vitamin A reserves and rely heavily on breast milk for their initial supply. If the mother is deficient, her breast milk will have low levels of vitamin A, putting the infant at high risk, especially after weaning onto diets that are often low in vitamins. This deficiency can manifest as night blindness, increase the risk of infectious diseases like measles and diarrhea, and can lead to irreversible blindness or death. The World Health Organization (WHO) and UNICEF have a long history of recommending vitamin A supplementation for children in at-risk areas to combat these outcomes.

Pregnant and lactating women

Pregnancy and lactation place an increased physiological demand on a woman's body, requiring higher vitamin A intake. This demand, coupled with often-poor dietary habits in low-income settings, leads to a high prevalence of VAD among women of childbearing age. A deficient mother's low vitamin A status impacts not only her own health, increasing her risk for night blindness and complications during childbirth, but also negatively affects her infant, who depends on her for the nutrient. Some research indicates maternal VAD may increase the risk of mortality for both the mother and infant.

Individuals with compromised dietary intake and health

Beyond specific life stages, vitamin A deficiency is prevalent among marginalized groups who experience chronic malnutrition and higher exposure to infectious diseases. These populations include individuals in refugee camps, areas of political instability, or those living below the poverty line where diverse food is scarce. Recurrent infections, such as measles and persistent diarrhea, are particularly problematic as they decrease appetite and impair vitamin A absorption, further driving down nutrient levels.

At-risk groups due to medical conditions

In developed nations where VAD is rare, it is almost exclusively found in individuals with underlying health conditions that interfere with nutrient absorption or metabolism.

Individuals with fat malabsorption disorders

Vitamin A is a fat-soluble vitamin, so any condition that impairs fat digestion and absorption can lead to a deficiency. This is a significant risk factor in developed countries and includes:

Cystic Fibrosis: Pancreatic insufficiency in individuals with cystic fibrosis severely impairs the absorption of fat and fat-soluble vitamins, including vitamin A.
Chronic Pancreatitis or Bile Duct Obstruction: Pancreatic or liver diseases that block bile flow reduce the body's ability to absorb fats and fat-soluble vitamins.
Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis cause chronic inflammation of the intestinal lining, disrupting nutrient absorption.
Bariatric Surgery: Weight-loss surgeries, particularly those that bypass the small intestine, can dramatically reduce the area available for nutrient absorption, leading to deficiencies.
Short Bowel Syndrome: Following extensive small bowel resection, patients cannot absorb sufficient nutrients, necessitating regular monitoring and supplementation.

People with alcohol use disorder

Chronic alcohol abuse can deplete the liver's stores of vitamin A and interfere with its absorption and metabolism. The liver is the primary organ for storing vitamin A, so damage from alcohol can significantly disrupt this process, making these individuals susceptible to deficiency.

Vegans and individuals with limited dietary variety

While the body can convert carotenoids from plant-based foods into vitamin A, this process is less efficient than obtaining preformed vitamin A from animal products. Individuals who follow a strict vegan diet without carefully planning their intake of orange and green leafy vegetables may be at a higher risk of insufficient vitamin A intake. Those with restricted dietary habits, including some individuals with autism spectrum disorder, can also be at risk due to a lack of dietary diversity.

Comparative risk factors for vitamin A deficiency


Risk Factor Category	Vulnerable Populations	Primary Mechanisms	Geographical Prevalence
Dietary	Children in low-income countries, pregnant and lactating women, vegans, and people with limited food access	Inadequate intake of vitamin A-rich foods, particularly animal products	High in developing countries, can be a risk factor in developed countries for specific dietary patterns
Physiological	Young children (especially 6-59 months), premature infants, pregnant and lactating women	Increased nutrient demands for growth, development, and milk production; low initial stores in newborns	Highest burden in low-income countries, but also a factor for premature infants and pregnant/lactating women in developed nations
Absorption/Metabolism	Individuals with cystic fibrosis, chronic pancreatitis, IBD, alcoholism, bariatric surgery, or liver disorders	Compromised fat digestion and absorption due to disease or surgical changes; impaired liver storage	Predominantly the cause of VAD in developed countries, though also relevant in developing countries with co-existing disease
Infections	Children in developing countries, individuals with poor sanitation and hygiene	Frequent infectious diseases (e.g., measles, diarrhea) decrease appetite and deplete nutrient stores	Most significant in low-income settings with high rates of infectious disease

Conclusion

Vitamin A deficiency is a complex nutritional problem influenced by both socioeconomic and health-related factors. While the majority of cases occur in young children and pregnant women living in low-income countries due to dietary inadequacy and high infection rates, certain medical conditions like fat malabsorption disorders place individuals in developed countries at risk. Effective prevention and management require a multi-pronged approach, including dietary diversification, food fortification, supplementation for vulnerable groups, and addressing underlying health issues. A heightened awareness of the specific populations at risk is crucial for implementing targeted and impactful public health strategies to eliminate this preventable health issue.

Frequently Asked Questions

Young children, particularly between 6 months and 5 years, are at high risk because their rapid growth increases the body's demand for vitamin A. Infants are born with low stores and rely on maternal breast milk, which can be low in vitamin A if the mother is deficient. After weaning, they often transition to diets that lack sufficient vitamin A.

While vitamin A deficiency is most prevalent in low- and middle-income countries, it is not exclusive to them. In developed nations, VAD is primarily associated with underlying medical conditions that interfere with nutrient absorption, such as fat malabsorption disorders, cystic fibrosis, and chronic liver disease.

Infections, especially common childhood illnesses like measles and diarrhea, can exacerbate vitamin A deficiency. They increase the body's metabolic demand for the nutrient and impair its absorption. Conversely, VAD weakens the immune system, making individuals more susceptible to severe and frequent infections.

As a fat-soluble vitamin, vitamin A requires dietary fat and a functioning digestive system for proper absorption. Conditions that cause fat malabsorption, such as cystic fibrosis, chronic pancreatitis, inflammatory bowel disease, or bariatric surgery, severely disrupt this process and lead to deficiency.

It is possible for individuals on a vegan diet to be at risk for vitamin A deficiency if they do not consume adequate amounts of provitamin A carotenoids. The conversion of carotenoids from plants to active vitamin A is less efficient than absorbing preformed vitamin A from animal sources, necessitating a thoughtful dietary approach.

The earliest and most common sign of VAD is night blindness, which is difficulty seeing in low light conditions. Other early signs can include very dry eyes (xerosis) and dry, scaly skin.

Treatment for vitamin A deficiency typically involves oral supplementation with high doses of vitamin A over several days, followed by lower maintenance doses. In cases of malabsorption or severe symptoms, parenteral (intramuscular) administration may be necessary.