---
title: "What does a low Folate mean?"
type: biomarker-interpretation
url: "https://www.test-well.com/biomarkers/folate/low"
biomarker: Folate
direction: low
reference_range:
  - "age 18+: 3.40 – 25.0 ng/mL"
reviewed_at: 2026-09-06
review_status: reviewed
date_published: 2026-09-05
---

# What does a low Folate mean?

> Low folate is usually dietary — few leafy greens, legumes or fortified grains — or from alcohol use, malabsorption (celiac disease), pregnancy's higher demand, or medications such as methotrexate, some anticonvulsants and sulfasalazine. It causes macrocytic anemia and fatigue, raises homocysteine, and in pregnancy raises the risk of neural-tube defects. B12 should be checked alongside, since treating folate alone can mask B12 deficiency.


## What is the normal range for Folate?

- age 18+: 3.40 – 25.0 ng/mL

Can reflect poor diet, alcohol use, certain medications, or absorption issues. Especially important before/during pregnancy.

## What are the common causes of low Folate?

1. Low dietary intake, alcohol use disorder
2. Malabsorption: celiac disease, inflammatory bowel disease, bariatric surgery
3. Pregnancy, breastfeeding, hemolytic anemia (increased demand)
4. Medications: methotrexate, phenytoin, trimethoprim, sulfasalazine
5. Some genetic variants (MTHFR) modestly affect folate metabolism

## What symptoms go with low Folate?

- Fatigue, weakness
- Sore tongue, mouth ulcers
- Irritability, low mood

## What do clinicians usually check next?

- Vitamin B12 (must be checked before treating folate alone)
- CBC with MCV
- Celiac screen if no dietary or medication cause
- Homocysteine if cardiovascular risk is being assessed

Follow-up tests at TestWell: [CBC with Differential](https://www.test-well.com/tests/cbc-with-differential) ($21.99), [CBC (Complete Blood Count)](https://www.test-well.com/tests/cbc) ($21.99), [Homocysteine](https://www.test-well.com/tests/homocysteine) ($27.99), [Vitamin B12](https://www.test-well.com/tests/vitamin-b12) ($25.99).

## How do you recheck Folate?

| Test or panel | Type | Price | Fasting | Results |
| --- | --- | --- | --- | --- |
| [Vitamin B12 & Folate](https://www.test-well.com/tests/vitamin-b12-and-folate) | Test | $36.99 | No | 2–4 business days |

Plus one $6 lab processing fee per order; physician authorization included.

## Common questions

### Why check B12 when folate is low?

Treating folate deficiency corrects the anemia but not the nerve damage of an undiagnosed B12 deficiency, which then progresses silently. Both are always checked together.

## Related

- [What does a high Folate mean?](https://www.test-well.com/biomarkers/folate/high)
- [Folate reference ranges](https://www.test-well.com/biomarkers/folate)
- [Vitamin D, 25-Hydroxy reference range](https://www.test-well.com/biomarkers/vitamin-d-25-hydroxy)
- [Vitamin B12 reference range](https://www.test-well.com/biomarkers/vitamin-b12)
- [Vitamin A (Retinol) reference range](https://www.test-well.com/biomarkers/vitamin-a-retinol)

## Sources

- [AACC Lab Tests Online](https://www.testing.com/tests/vitamin-b12-and-folate/)

---

Medically reviewed by Youmna DiStefano, MD (Medical Reviewer, TestWell); last reviewed 2026-09-06. Review policy: https://www.test-well.com/editorial-policy

Canonical page: https://www.test-well.com/biomarkers/folate/low
Machine-readable catalog: https://www.test-well.com/api/catalog.json · MCP server: https://www.test-well.com/mcp · Overview for agents: https://www.test-well.com/llms.txt

Prices are cash-pay, in USD, and include physician authorization; every order adds one flat $6 lab processing fee. Educational content is not a diagnosis — discuss results with a clinician.