What are the main causes and signs/symptoms of folate deficiency?

    Written by:
    Katie Jantz

    Fact-checked

    by:

    Nick Milazzo
    Last Updated: May 16, 2025

    Folate deficiency can arise from insufficient dietary intake, certain medications, impaired absorption, pregnancy, and genetic factors. Symptoms include fatigue, poor concentration, tachycardia, irritability, dizziness, pale skin, and a painful red tongue, and megaloblastic anemia is the primary clinical sign.

    Folate deficiency can occur for several reasons, including:[1][2][3][4]

    • Insufficient dietary intake
    • Certain medications (e.g., methotrexate, antiepileptics, oral contraceptives)
    • Impaired absorption (e.g., celiac disease, gastric bypass, alcohol use disorder)
    • Pregnancy (due to an increased biological demand for folate)
    • Genetic polymorphisms (e.g., MTHFR, DHFR)

    A folate deficiency can be diagnosed by doing a blood test, as the primary clinical sign is a type of anemia characterized by abnormally large and underdeveloped red blood cells (megaloblastic anemia).[4] Symptoms of deficiency can include fatigue, poor concentration, increased heart rate (tachycardia), irritability, dizziness, pale skin, and a painful red tongue.[2]