What Would Cause My Folate to Be Low?

January 2, 2026 •

3 min read

According to the CDC, folic acid fortification of grains has significantly reduced the incidence of folate deficiency in the United States, yet it remains a concern for specific populations. A folate deficiency can be caused by various factors, from diet and lifestyle to underlying health conditions and certain medications. Since the body doesn't store large amounts of folate, consistent intake is crucial to prevent levels from dropping.

Quick Summary

Folate deficiency can result from inadequate dietary intake, excessive alcohol use, or malabsorption issues due to gastrointestinal diseases like celiac disease or Crohn's disease. Other causes include certain medications, increased physiological demand during pregnancy, and genetic variations like the MTHFR polymorphism.

Key Points

Dietary Insufficiency: Not consuming enough folate-rich foods, or overcooking them, is the most common cause of a folate deficiency.
Malabsorption Issues: Chronic diseases like celiac disease, Crohn's disease, and even some stomach surgeries can prevent the small intestine from absorbing folate properly.
Alcohol Use: Excessive alcohol consumption directly interferes with folate absorption and metabolism, increasing its excretion.
Medication Side Effects: Certain drugs, including methotrexate and some anticonvulsants, can block the body's ability to use or absorb folate.
Increased Physiological Demand: Pregnancy, breastfeeding, and chronic conditions like hemolytic anemia and cancer drastically increase the body's need for folate.
Genetic Factors: A mutation in the MTHFR gene can impair the body's ability to convert folate into its active, usable form.

Common Causes of Folate Deficiency

Folate is a B vitamin essential for cell growth, DNA formation, and red blood cell production. When a person's folate level is low, it can lead to various health problems, most notably megaloblastic anemia. Understanding the root cause is the first step toward effective treatment. Below are some of the most frequent culprits behind a folate deficiency.

Dietary Factors

Inadequate dietary intake is the most common cause of low folate levels. Folate is a water-soluble vitamin, meaning the body doesn't store it for extended periods and needs a consistent supply from food. The following dietary habits can contribute to a deficiency:

Low intake of folate-rich foods: A diet lacking fresh fruits, leafy green vegetables, legumes, and fortified cereals is a primary risk factor.
Overcooking food: Folate is sensitive to heat and can be destroyed when food is overcooked.
Alcohol consumption: Excessive alcohol use impairs folate absorption and increases its excretion through urine, leading to reduced folate stores.

Malabsorption and Gastrointestinal Disorders

Even with a folate-rich diet, certain conditions can prevent your body from properly absorbing the nutrient. These malabsorptive disorders include:

Celiac disease: This autoimmune disorder damages the lining of the small intestine, hindering nutrient absorption, including folate.
Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can lead to inflammation and damage in the digestive tract, impairing absorption.
Hereditary folate malabsorption: A rare genetic condition caused by mutations in the SLC46A1 gene, which disrupts the transport of folate into the cells.
Gastric surgeries: Procedures that remove parts of the stomach or intestines can significantly impact the body's ability to absorb folate.

Medications and Drug Interactions

Several common medications can interfere with folate absorption or metabolism, leading to deficiency over time. It is crucial to discuss any long-term medication use with a healthcare provider to manage this risk.

Table: Common Medications Affecting Folate Levels


Medication Type	Examples	Mechanism of Action	Potential Result
Anticonvulsants	Phenytoin, Phenobarbital	Can interfere with folate absorption and metabolism.	Reduced folate levels and potential for megaloblastic anemia.
Folate Antagonists	Methotrexate, Trimethoprim	Act as enzyme inhibitors that block the use of folate by cells.	Rapidly depletes folate, especially in high-demand situations like chemotherapy.
Sulfonamides	Sulfasalazine	Can inhibit folate absorption and its bacterial synthesis in the gut.	Can lead to folate deficiency, particularly in patients with IBD.
Other Medications	Oral contraceptives, Some diuretics	Can alter folate metabolism or increase excretion in some individuals.	Variable effects on folate, often managed with supplementation.

Increased Physiological Demand

Certain life stages and medical conditions increase the body's need for folate, making it easier to become deficient if not properly managed.

Pregnancy and Breastfeeding: The high cellular division and rapid growth during pregnancy significantly increase folate requirements. A deficiency can lead to serious birth defects, such as neural tube defects.
Hemolytic Anemia: This condition involves the premature destruction of red blood cells, which increases the body's demand for folate to produce new cells.
Chronic Dialysis: Patients undergoing kidney dialysis experience significant folate loss, necessitating supplementation.
Cancer: Rapidly dividing cancer cells can consume large amounts of folate, increasing the body's overall demand.

Genetic Variations

Genetic factors can influence how the body processes and uses folate. The most widely known is a polymorphism in the MTHFR gene, which stands for methylenetetrahydrofolate reductase.

MTHFR polymorphism: Some individuals have a genetic variant that impairs the enzyme responsible for converting folate into its active form, 5-MTHF. This can result in lower active folate levels, despite adequate dietary intake.

Conclusion

Low folate levels are not always a simple dietary issue; they can arise from a complex interplay of dietary habits, medical conditions, medications, and genetics. While an inadequate diet is the most common cause, individuals with gastrointestinal disorders, those taking certain medications, and those with increased physiological needs must be particularly vigilant. If you suspect you have a folate deficiency based on symptoms like fatigue, irritability, or a sore tongue, it is essential to consult a healthcare professional for proper diagnosis and treatment. A blood test can confirm the deficiency, and your doctor can help you determine the underlying cause and the most effective course of action, which may include dietary changes, supplementation, or addressing an underlying health issue.

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Note: The information provided here is for informational purposes only and does not constitute medical advice. Consult a healthcare professional for diagnosis and treatment.

Frequently Asked Questions

To increase folate levels, focus on incorporating leafy green vegetables like spinach and broccoli, citrus fruits, legumes (beans and lentils), eggs, and fortified grains into your diet. Overcooking should be avoided as it can destroy the vitamin.

Doctors typically diagnose a folate deficiency using a blood test to measure serum folate levels. They may also check for signs of megaloblastic anemia in a complete blood count and test for vitamin B12 levels, as symptoms can overlap.

Yes, a severe folate deficiency can lead to psychological problems. Symptoms can include depression, irritability, and confusion, particularly in older adults.

Folate is the naturally occurring form of vitamin B9 found in foods, while folic acid is the synthetic form used in supplements and fortified foods. The body absorbs folic acid more readily than naturally occurring folate.

Yes, a folate deficiency during pregnancy is dangerous and can significantly increase the risk of serious birth defects, particularly neural tube defects like spina bifida. Pregnant women are advised to take folic acid supplements.

Yes, a folate deficiency is a common cause of a type of anemia called megaloblastic anemia, where the bone marrow produces abnormally large, immature, and poorly functioning red blood cells.

MTHFR is a gene that helps the body convert folate into its active form. A genetic variant in this gene can reduce the efficiency of this conversion, potentially leading to low active folate levels.