Folate — Red Blood Cell Status
RBC folate reflects long-term folate status better than serum folate. Required for methylation, DNA synthesis, and homocysteine clearance.
Red blood cell (RBC) folate reflects long-term folate status better than serum folate, which fluctuates with recent meals. Folate is required for methylation, DNA synthesis, and homocysteine clearance, and is critical in pre-conception and pregnancy.
The biomarker
- Name: Folate (RBC)
- Units: ng/mL
- Standard reference range: > 280 (deficient < 100)
- Optimal range: > 400
How to read your result
| Value | Interpretation |
|---|---|
| < 100 | Deficient — investigate and supplement |
| 100–280 | Low |
| 280–400 | Borderline |
| ≥ 400 | Adequate |
What moves the needle
- Diet. Leafy greens, legumes, citrus.
- Testing. Pair with B12 and homocysteine.
- Supplement. Methylfolate if MTHFR variant or pregnancy planned; doses vary, see your source.
Why this test is worth asking for
- RBC folate reflects long-term status, so it avoids the meal-to-meal noise that makes serum folate unreliable.
- Folate underpins methylation, DNA synthesis, and homocysteine clearance — a low result has reach well beyond a single symptom.
- It is critical in pre-conception and pregnancy, where adequate stores matter before they are needed.
Related protocols
- Vitamin D — 25-Hydroxyvitamin D
- Vitamin B12 + Methylmalonic Acid (MMA)
- TSH, Free T3 and T4 — Thyroid Panel
Sources
AgeGen lab guides are educational only. We do not provide medical diagnosis, prescribe brands, or recommend specific doses. Talk to a licensed clinician before changing your supplement or medication routine.