Folate Deficiency Test: Check Your Symptoms Online

Based on NIH Office of Dietary Supplements guidance · Last reviewed: July 15, 2026 · How we source our content

Folate (vitamin B9) is essential for making new cells — which is exactly why it matters so much in pregnancy, and why deficiency shows up first in the tissues that turn over fastest: blood cells and the lining of your mouth and gut. Unlike B12, your body only stores a few months' worth, so a poor diet can produce a deficiency far faster than most people expect.

Fatigue, mouth sores, pale skin?

Our free assessment weighs your symptoms and diet in about 2 minutes.

What low folate feels like

  • Fatigue and weakness — from the anemia folate deficiency eventually causes
  • Mouth sores or a swollen, sore tongue — one of the more distinctive early signs
  • Pale skin
  • Irritability and difficulty concentrating
  • Shortness of breath and headaches as anemia progresses

These overlap heavily with B12 deficiency because both cause the same type of anemia through a related mechanism — which is why the two are almost always considered together rather than one at a time.

Who needs to pay closer attention

Anyone who could become pregnant

Folic acid prevents neural tube defects in the first weeks of pregnancy — often before pregnancy is confirmed, which is why the recommendation starts before conception.

Regular alcohol drinkers

Alcohol both blocks absorption and increases excretion of folate, and often displaces folate-rich food from the diet.

People with malabsorption conditions

Celiac disease and Crohn's disease both reduce how much folate the gut can absorb.

People on certain medications

Some anti-seizure drugs and methotrexate interfere with folate metabolism directly.

How our test approaches it

Because folate and B12 deficiency present so similarly, our free assessment weighs your symptoms against both at once, along with your diet, alcohol use and pregnancy status — the three factors that most reliably separate a folate problem from a B12 one. Correctly identifying which is which matters clinically, since treating one while missing the other can mask important symptoms.

If you are low

Leafy greens, legumes, asparagus, avocado and fortified grains are all strong sources — and in many countries, bread and cereal products are fortified with folic acid specifically to reduce population deficiency rates. Most adults need 400 mcg/day, rising to 600 mcg/day for pregnancy and 500 mcg/day while breastfeeding. Because your reserves are smaller than B12's, correcting a deficiency through diet or a modest supplement usually shows improvement within a few weeks.

Frequently asked questions

Related but not identical. Folate is the natural form in food (leafy greens, legumes, liver). Folic acid is the synthetic form in supplements and fortified foods, which the body converts to the active form. Both count toward your daily requirement.

Neural tube defects — the main risk folic acid protects against — occur in the first 3-4 weeks of pregnancy, often before a person knows they're pregnant. That's why anyone who could become pregnant is advised to take 400 mcg daily, not just those with a confirmed pregnancy.

Yes. Both cause a similar anemia, and high-dose folic acid can correct the blood-count abnormality of a B12 deficiency while the underlying nerve damage continues untreated. Doctors typically check both together rather than one in isolation.

Significantly. Alcohol interferes with folate absorption and increases excretion, while often displacing folate-rich foods from the diet. Regular drinkers are one of the higher-risk groups for deficiency.

Related checks and reading

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