Anemia Biomarker
Collection Type: Blood
Related System: Anemia
Serum folate measures the circulating level of folate (vitamin B9) in blood and reflects recent dietary intake. Folate is essential for DNA synthesis, red blood cell production, and homocysteine metabolism. Low levels suggest folate deficiency, which can cause megaloblastic (macrocytic) anemia, fatigue, pallor, glossitis, and in pregnancy increased risk of neural tube defects. Elderly, pregnant people, those on certain medications, alcohol users, or with malabsorption may have different expected levels.
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Q: What does serum folate mean?
A: Serum folate is the concentration of folate (vitamin B9) in blood serum and reflects recent dietary intake and short-term folate status. It’s tested when anemia, pregnancy planning, or malabsorption are concerns. Low serum folate suggests inadequate intake or absorption and risk of megaloblastic anemia; long-term folate stores are better assessed by red blood cell folate. High levels usually indicate supplementation.
Q: What happens if your folate serum is low?
A: Low serum folate leads to megaloblastic (macrocytic) anemia causing fatigue, pallor, weakness, shortness of breath, and glossitis. It can cause GI symptoms, poor growth, and in pregnancy raises neural-tube defect risk. Lab findings include elevated MCV, hypersegmented neutrophils, and high homocysteine. Prolonged deficiency may cause neuropathy. Treatment is dietary improvement and folic acid supplementation.
Q: What if my folate serum is high?
A: What if my folate serum is high? High serum folate most commonly reflects recent folic‑acid supplements or fortified foods, but can also occur with liver disease or altered clearance. While mildly elevated levels are usually benign, excess folic acid can mask vitamin B12 deficiency by correcting anemia while allowing neurologic damage to progress. Ask your clinician to review supplements, check B12 and methylmalonic acid, and repeat testing before changing therapy.
Q: Is folate and B12 the same thing?
A: Folate (vitamin B9) and vitamin B12 (cobalamin) are different vitamins with related roles. Both support DNA synthesis and red blood cell formation, but B12 is essential for nerve function and requires intrinsic factor for absorption, while folate is abundant in leafy greens and fortified foods. Deficiencies cause megaloblastic anemia; only B12 deficiency produces lasting neurological damage.
Q: How do you treat low folate levels?
A: Treat low folate by addressing the cause, improving diet (leafy greens, legumes, fortified cereals) and taking folic acid supplements—commonly 400–1000 µg daily; higher doses (1–5 mg/day) or parenteral folate are used for malabsorption or severe deficiency. Check and treat B12 deficiency first, stop offending drugs/alcohol if possible, and monitor blood counts and folate levels after 4–8 weeks.
Q: What disease can cause low folate?
A: Several diseases can cause low folate levels, especially malabsorption disorders such as celiac disease, Crohn’s disease, and short-bowel syndrome. Chronic alcoholism, persistent hemolytic anemias, and chronic liver disease can deplete folate. Certain cancers and increased demands in pregnancy or hemolysis also lower folate. Some medications (e.g., methotrexate, anticonvulsants) further contribute to deficiency.