RBC Folate measures the amount of folate stored inside your red blood cells, providing a more accurate picture of your long-term folate status than serum folate testing.
RBC (Red Blood Cell) Folate measures the folate incorporated into red blood cells during their formation in the bone marrow. Since red blood cells live approximately 120 days, this test reflects your average folate status over the past 3-4 months rather than recent dietary intake.
This makes RBC folate the gold standard for assessing true folate deficiency, as serum folate can fluctuate based on recent meals or supplements. RBC folate is particularly valuable when serum folate is borderline or when there's clinical suspicion of deficiency despite normal serum levels.
Low RBC folate definitively indicates tissue folate depletion and is strongly associated with megaloblastic anemia, elevated homocysteine, and neural tube defect risk during pregnancy.
Price
$17
Results
2-3 days
Lab Network
Quest
Fasting
Not Required
What's Measured
What This Test Measures
This test measures folate concentration within red blood cells, reported in ng/mL. Normal RBC folate typically ranges from 280-791 ng/mL. Values below 280 ng/mL indicate deficiency requiring supplementation.
Who Should Consider This Test
Anyone with suspected folate deficiency despite normal serum levels, patients with malabsorption syndromes, women with history of neural tube defect pregnancies, individuals with unexplained macrocytic anemia, and those requiring comprehensive nutritional assessment.
Health Insights
Conditions Screened
Related Symptoms
When to Get Tested
No fasting required. Can test anytime. Results reflect status over the past 3-4 months, so recent dietary changes won't significantly affect results. Ideal for accurate baseline assessment.
Understanding Your Results
Normal RBC folate is 280-791 ng/mL. Below 280 ng/mL confirms deficiency. Because RBC folate reflects long-term stores, low values indicate true tissue depletion requiring supplementation and possibly investigation of underlying causes.
What to Expect
After placing your order, you'll receive an email from Rupa Health (our lab order partner) within 24 business hours to sign a consent form and schedule your blood draw at a Quest Diagnostics location.
The blood draw typically takes just a few minutes. Results are usually available within 2-3 business days and will appear in your secure Justlabs dashboard.
Our results include reference ranges and easy-to-understand indicators showing whether your values are within normal limits.
Frequently Asked Questions
$17
Typical hospital cash price: $100–$200
+ $28 in standard lab & physician fees at checkout (no additional bills later)
$18 lab collection + $10 physician order
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