How can you get vitamin A deficiency?

December 15, 2025 •

4 min read

According to the World Health Organization, vitamin A deficiency is a public health problem in more than half of all countries, particularly in Africa and Southeast Asia. Knowing how you can get vitamin A deficiency is essential, as it often results from a combination of inadequate dietary intake, medical conditions affecting absorption, and other significant risk factors.

Quick Summary

Several factors contribute to inadequate vitamin A levels, including insufficient dietary intake, poor fat absorption from certain medical conditions, and compromised liver function affecting storage. Genetic predispositions and chronic alcohol consumption also play a significant role.

Key Points

Inadequate Diet: Consistently low intake of vitamin A-rich foods, including animal products (retinol) and colorful plants (carotenoids), is a leading cause of deficiency.
Fat Malabsorption: Conditions like cystic fibrosis, celiac disease, and Crohn's disease prevent the body from properly absorbing the fat needed to utilize vitamin A.
Liver Disorders: Since the liver stores most of the body's vitamin A, diseases like cirrhosis can interfere with its storage and release.
Chronic Alcohol Abuse: Alcoholism impairs intestinal absorption and depletes the liver's vitamin A reserves by affecting its metabolism and storage.
Increased Requirements: Infants, young children, and pregnant or lactating women have higher vitamin A needs, making them more susceptible to deficiency, especially in low-income regions.
Frequent Infections: Diseases like measles and persistent diarrhea can deplete vitamin A stores and create a cycle of worsened immune function and nutrient loss.
Genetic Factors: Some individuals have genetic variations that reduce their ability to convert provitamin A carotenoids from plants into the active form, increasing the risk for vegans.

Primary Cause: Inadequate Dietary Intake

The most straightforward path to developing a vitamin A deficiency is through a diet consistently lacking in foods rich in this essential nutrient. Vitamin A comes in two forms: preformed vitamin A (retinol), found in animal products, and provitamin A carotenoids, found in plants. A diet that excludes or severely limits these sources without proper supplementation is a leading cause of deficiency, particularly in developing countries where food insecurity is widespread.

The Challenge for Plant-Based Diets

While many plant foods contain carotenoids like beta-carotene, which the body can convert to vitamin A, this process is not always efficient. The conversion rate can be affected by factors such as genetics, the presence of fat in the meal, and the way the food is processed. Individuals with genetic variations (single nucleotide polymorphisms or SNPs) may have a reduced ability to convert beta-carotene into the active form of vitamin A, potentially increasing their risk of deficiency on a strictly vegan diet without proper planning or supplementation. To prevent this, vegans should prioritize a variety of deeply colored fruits and vegetables and consume them with a source of fat.

Medical Conditions Affecting Absorption and Storage

For many in developed nations, a vitamin A deficiency is not caused by diet alone, but by an underlying medical issue that interferes with the body’s ability to absorb, transport, or store the vitamin. Since vitamin A is fat-soluble, proper fat absorption is critical.

Digestive Disorders

Chronic conditions that affect the digestive system are a significant cause of malabsorption. The following conditions disrupt the normal digestive process and can lead to a deficiency:

Cystic Fibrosis: This genetic disorder causes thick mucus to block pancreatic ducts, preventing digestive enzymes from reaching the intestine to break down fat.
Celiac Disease: In those with celiac disease, the immune system reacts to gluten, damaging the small intestine's lining and impairing its ability to absorb nutrients, including fat-soluble vitamins.
Crohn's Disease and Inflammatory Bowel Disease (IBD): Inflammation of the digestive tract in these conditions can compromise nutrient absorption.
Chronic Diarrhea: Prolonged or chronic diarrhea can flush nutrients from the body before they can be properly absorbed.

Liver and Pancreatic Disease

Liver Disorders: The liver is the primary organ for storing 80-90% of the body's vitamin A reserves. Any liver disease that impairs this function, such as cirrhosis, can lead to a deficiency even with adequate dietary intake.
Pancreatic Insufficiency: A lack of pancreatic enzymes can prevent fat from being broken down, which is necessary for vitamin A absorption.

Surgical Procedures

Patients who have undergone certain surgeries, particularly those affecting the small intestine or pancreas, are at a higher risk of developing a vitamin A deficiency. This is common after bariatric surgery or small bowel bypass surgery, where parts of the digestive tract are rerouted or removed, limiting the area for nutrient absorption.

Other Significant Risk Factors

Beyond diet and underlying health issues, other factors can put individuals at risk:

Chronic Alcohol Abuse: Alcoholism negatively impacts vitamin A metabolism in several ways. It can decrease intestinal absorption, inhibit the enzymes that convert and transport retinol, and deplete the liver's storage capacity.
Infections: Certain infections, such as measles, can deplete vitamin A reserves and increase the body's metabolic demand, precipitating a deficiency. Recurrent infections, especially diarrheal diseases, create a vicious cycle of illness and nutrient depletion.
Age and Physiological State: Certain populations have a higher vitamin A requirement, making them more vulnerable. These include infants (especially premature), young children (6 months to 5 years old), and pregnant or lactating women.
Protein-Energy Malnutrition: Severe malnutrition, which involves deficiencies in protein and calories, can impair the synthesis of retinol-binding protein (RBP), preventing the stored vitamin A from being properly transported from the liver to other tissues.

How to Prevent Vitamin A Deficiency

Prevention is primarily centered on addressing the root cause, whether it's dietary, medical, or lifestyle-related. For most people, a balanced diet is sufficient, but individuals with risk factors may need medical management.

Here is a comparison of different approaches to prevention:


Prevention Method	Target Group	Recommended Actions	Key Considerations
Dietary Strategies	General population; vegans and vegetarians	Consume a variety of vitamin A-rich foods: leafy greens, orange fruits/vegetables, liver, dairy, eggs, and fortified foods.	Pair carotenoids with a source of fat to enhance absorption. Focus on whole foods.
Medical Management	Individuals with malabsorption diseases (e.g., cystic fibrosis, IBD, celiac)	Work with a healthcare provider to manage the underlying condition and discuss supplementation.	Needs consistent monitoring and tailored dosing to avoid toxicity. Often involves high-dose, short-term supplementation followed by maintenance.
Prophylactic Supplementation	At-risk populations in developing countries; infants and young children	Administering high-dose vitamin A supplements at regular intervals as recommended by public health organizations like the WHO.	Crucial in areas with high deficiency prevalence to reduce childhood mortality and blindness.
Lifestyle Changes	Individuals with chronic alcohol use disorder	Reduce or eliminate alcohol consumption and receive nutritional counseling to correct deficiencies.	Alcohol metabolism directly interferes with vitamin A, so reducing intake is a core part of treatment.

Conclusion

Vitamin A deficiency is a global health concern with multiple pathways to development. While dietary inadequacy is the most common cause worldwide, particularly in populations affected by poverty, underlying medical conditions like malabsorption disorders, liver disease, and chronic alcohol abuse are primary drivers in developed nations. The body's intricate systems for absorbing, converting, and storing vitamin A can be disrupted by various factors, including genetics and the presence of infections. For those at risk, preventive strategies range from consuming a nutrient-rich diet with proper fat intake to targeted medical management and supplementation, especially for vulnerable groups like young children and individuals with malabsorptive conditions. Consult a healthcare professional if you suspect a deficiency to determine the best course of action.

For more detailed dietary information, the National Institutes of Health provides a comprehensive resource on vitamin A sources and recommendations: Dietary Supplement Fact Sheet: Vitamin A and Carotenoids.

Frequently Asked Questions

The most common cause globally is an inadequate dietary intake of vitamin A-rich foods, which is widespread in developing countries due to poverty and food insecurity.

A vegan diet can lead to vitamin A deficiency if not carefully planned. While carotenoids in plants can be converted to vitamin A, this process is less efficient than getting preformed vitamin A from animal products and can be affected by genetics and fat intake.

Chronic alcohol consumption can cause vitamin A deficiency by impairing intestinal absorption, depleting liver stores, and interfering with the enzymes responsible for vitamin A metabolism and transport.

Digestive conditions that interfere with fat absorption, and therefore vitamin A absorption, include cystic fibrosis, celiac disease, inflammatory bowel disease (IBD), and chronic diarrhea.

Infants and young children have higher vitamin A requirements due to rapid growth and a greater susceptibility to infectious diseases, which can rapidly deplete their limited reserves.

Frequent or severe infections, such as measles or persistent diarrhea, can deplete the body's vitamin A stores, weakening the immune system and increasing susceptibility to further illness in a cycle of worsening health.

Yes, surgical procedures like bariatric or small bowel bypass surgery can increase the risk of vitamin A deficiency by altering the digestive tract and limiting the surface area available for nutrient absorption.