What Would Cause Folic Acid Deficiency?

November 24, 2025 •

3 min read

According to the CDC, mandatory fortification of grains with folic acid has significantly reduced the prevalence of folate deficiency in many countries. However, a range of other factors can still cause folic acid deficiency, highlighting the importance of understanding the root causes to protect your health.

Quick Summary

An inadequate diet, malabsorption issues from digestive diseases, certain medications, excessive alcohol use, and increased physiological demand during pregnancy can all lead to a deficiency. Genetic factors and other medical conditions also play a role.

Key Points

Inadequate Diet: Not eating enough folate-rich foods like leafy greens, fruits, and fortified cereals is a primary cause of deficiency.
Malabsorption Issues: Digestive diseases like Crohn's and Celiac disease can prevent the proper absorption of folate in the intestines.
Medications: Certain drugs, including methotrexate and some anti-seizure medications, can interfere with the body's folate metabolism.
Increased Demand: Pregnancy and medical conditions like chronic hemolytic anemia significantly increase the body's need for folate.
Alcohol Use: Excessive alcohol consumption disrupts folate absorption, storage, and increases urinary excretion.
Overcooking: Prolonged heat exposure can destroy the folate naturally present in foods.
Underlying Genetic Factors: Rare genetic conditions, like hereditary folate malabsorption, can impair folate transport and utilization.

Introduction to Folic Acid and Its Importance

Folic acid, the synthetic form of folate (vitamin B9), is an essential nutrient crucial for many bodily functions. It plays a vital role in DNA and RNA synthesis, cell growth, and the formation of healthy red blood cells. A deficiency can lead to megaloblastic anemia, where red blood cells are abnormally large and immature, reducing their ability to carry oxygen efficiently. For pregnant women, adequate folic acid intake is especially critical for fetal development to prevent neural tube defects like spina bifida. Understanding the various factors that disrupt folate levels is key to maintaining overall health.

The Role of Dietary Factors

Dietary insufficiency is a leading cause of low folate levels. The body's limited folate stores mean consistent intake of folate-rich foods is essential. Folate is heat-sensitive, and overcooking can reduce its nutritional value.

Poor Diet: A lack of fruits, vegetables, and fortified grains is a primary contributor, often seen in those with unbalanced or restrictive diets, or older adults.
Overcooking: Excessive heat during cooking can destroy a significant amount of folate in foods.
Excessive Alcohol Consumption: Chronic alcohol use impairs folate absorption, metabolism, and increases its excretion.

Medical Conditions Affecting Absorption

Certain health issues can hinder the body's ability to absorb or use folate.

Malabsorption Syndromes: Conditions like Celiac disease and inflammatory bowel diseases can damage the small intestine, impeding folate absorption.
Intestinal Surgery: Procedures affecting the small intestine can reduce the area for nutrient absorption.
Kidney Dialysis: Dialysis can lead to increased folate loss, often requiring supplementation.
Hereditary Folate Malabsorption: This rare genetic disorder affects the body's ability to absorb and transport folate.

Medications and Folic Acid

Some medications interfere with folate metabolism.

Methotrexate: This drug inhibits an enzyme necessary for converting folate to its active form.
Certain Anti-seizure Medications: Drugs like phenytoin can interfere with enzymes needed for folate absorption.
Other Medications: Sulfasalazine and trimethoprim can also reduce folate absorption or utilization.

Increased Physiological Needs

Increased bodily demands for folate can also cause deficiency.

Pregnancy and Lactation: Rapid cell growth during pregnancy increases folate needs significantly.
Chronic Hemolytic Anemia: Conditions causing rapid red blood cell destruction increase the demand for folate.
Cancer: Increased cell turnover in some cancers can raise folate requirements.

Comparison of Major Causes of Folic Acid Deficiency


Cause Category	Specific Factor	Mechanism Leading to Deficiency	Common Populations Affected
Dietary Insufficiency	Inadequate Diet	Lack of intake of folate-rich foods like leafy greens, legumes, and fortified grains.	Older adults, individuals with unbalanced eating habits, alcohol users
	Overcooking Food	Heat-sensitive folate is destroyed during the cooking process.	Anyone who overcooks food; cultural cooking methods may increase risk
Malabsorption	Celiac/Crohn's Disease	Damage to the small intestine lining impairs nutrient absorption.	Individuals with diagnosed digestive disorders
	Gastric Surgery	Reduced intestinal surface area following procedures like gastric bypass limits absorption.	Post-bariatric surgery patients
Medications	Methotrexate	Inhibits the enzyme needed to convert folate to its active form.	Cancer, rheumatoid arthritis, or psoriasis patients
	Anti-seizure Drugs	Interfere with mucosal folate absorption in the intestine.	Epilepsy patients
Increased Requirement	Pregnancy	Rapid cell growth and division of the fetus and placenta increase demand.	Pregnant women
	Chronic Hemolysis	Accelerated red blood cell production due to constant destruction increases folate need.	Individuals with sickle cell anemia

Conclusion

Folic acid deficiency results from a combination of factors including poor diet, malabsorption, certain medications, and increased bodily needs. While fortification has helped, vulnerable populations remain. Understanding these causes is vital for prevention and treatment. Those at risk, such as pregnant women or individuals with digestive issues or on specific medications, may require supplementation and dietary changes. Consult a healthcare provider for concerns. For more information, refer to the CDC's resources on folate and folic acid.

Frequently Asked Questions

The most common cause of folic acid deficiency is not eating a diet rich in folate-containing foods, such as dark green leafy vegetables, citrus fruits, and legumes, or foods fortified with folic acid.

Chronic alcohol consumption can cause folate deficiency by damaging the intestinal lining and reducing absorption, impairing liver storage and metabolism, and increasing the amount of folate lost through urine.

Yes, several medications can cause a deficiency. These include the cancer and anti-inflammatory drug methotrexate, certain anti-seizure medications (like phenytoin), and drugs used for inflammatory bowel disease (like sulfasalazine).

During pregnancy, the body's need for folic acid increases significantly due to the rapid cell division required for fetal growth and placenta development. Insufficient intake can lead to serious birth defects, such as neural tube defects.

Gastrointestinal conditions such as Celiac disease, Crohn's disease, and surgical removal or bypass of parts of the small intestine can all lead to malabsorption and folate deficiency.

Yes, folate is sensitive to heat, and prolonged or excessive cooking of fruits and vegetables can destroy a large percentage of its nutritional content, reducing the amount the body receives.

Yes, in rare cases, a person can have hereditary folate malabsorption, a genetic disorder caused by a mutation in the SLC46A1 gene, which impairs the transport and absorption of folate.