Folate (folic acid)

What is Folate (folic acid)?

Folate (sometimes called vitamin B9) is a water-soluble B vitamin. "Folate" is the form found naturally in food; "folic acid" is the form used in supplements and fortified foods, and it is absorbed better.^[1]

Intake is measured in dietary folate equivalents (DFE), which account for folic acid being absorbed better than food folate.^[1]

Its role in the body

• Needed to make DNA and for cells to divide, so it is especially important when the body is growing fast, as in pregnancy.^[1]
• Needed to make normal red blood cells.^[1]
• Works with vitamin B12 in processing an amino acid called homocysteine.^[1]

Important food sources

• Dals, chana, rajma, lobia (black-eyed peas) and other legumesGood everyday Indian sources.
• Dark green leafy vegetables such as spinach, methi and amaranth
• Other vegetables and fruits, such as asparagus, broccoli, oranges and other citrus
• Nuts and peanuts
• Eggs, dairy and liverLiver is rich in folate but also very high in vitamin A, which matters in pregnancy.
• Fortified foodsSome cereals, flours and rice are fortified with folic acid; check the label.

Recommended dietary intake

Signs sometimes associated with low levels

• The main sign is megaloblastic anaemia (large, abnormal red blood cells), which can cause weakness, tiredness, difficulty concentrating, irritability, headache, palpitations and shortness of breath.^[1]
• Low folate on its own is uncommon; it usually comes with other nutrient problems linked to poor diet, heavy alcohol use or poor absorption.^[1]

Why symptoms alone cannot confirm a deficiency

Signs like tiredness, weakness, hair fall or low mood are very common and have many possible causes, such as poor sleep, stress, infections, thyroid problems or other illnesses.

The same sign can come from several different nutrients, or from no nutrient problem at all.

Only a qualified clinician, using your history, an examination and, when needed, lab tests, can say whether a deficiency is present. This app cannot diagnose a deficiency from symptoms or from BMI.

Low vitamin B12 causes the same kind of anaemia. Treating with folate alone when B12 is the real problem can hide the anaemia while nerve damage continues, which is why proper testing matters.

Tests a clinician might consider

• Serum folate reflects recent intake; red blood cell (erythrocyte) folate reflects longer-term status.^[1]
• A complete blood count, and vitamin B12 tests to rule out B12 deficiency. Homocysteine may also be checked.^[1]

Who is more likely to have low intake

• People with alcohol use disorder.^[1]
• Women who could become pregnant, and pregnant women.^[1]
• People with conditions that reduce absorption, such as celiac disease or inflammatory bowel disease.^[1]
• People with a common gene variant (MTHFR 677C>T) that makes folate processing less efficient.^[1]

Potential benefits and quality of evidence

• Enough folic acid around the time of conception prevents a substantial share of neural tube defects (such as spina bifida).^[1] Established
• Folic acid, often within multivitamins, may lower the risk of some other birth defects such as congenital heart defects; results are less consistent.^[1] Limited evidence
• Whether folic acid supplements lower the risk of heart disease, stroke, dementia, depression or cancer is unclear, and some studies raise concerns about high intakes and cancer.^[1] Not enough evidence

Side effects

• Folate from food is not known to cause harm.^[1]

Risks of too much

• High intakes of folic acid can mask vitamin B12 deficiency by correcting its anaemia while nerve damage continues, and may worsen B12-related anaemia and memory problems.^[1]
• Some research has linked high folic acid intakes with increased cancer risk; this is not settled.^[1]

Medicine and supplement interactions

• Methotrexate: Methotrexate works against folate. People taking it for cancer should ask their oncologist before taking folate. For other conditions, doctors sometimes prescribe folate alongside it — follow medical advice.^[1]
• Anti-seizure medicines (e.g., phenytoin, carbamazepine, valproate): Can lower folate levels; folate supplements may also lower levels of these medicines, so the doctor should be involved.^[1]
• Sulfasalazine (for ulcerative colitis): Reduces folate absorption and can cause deficiency.^[1]

Never start, stop or change a prescribed medicine because of this list — talk to your doctor or pharmacist.

Pregnancy and breastfeeding

• Folate is very important before and during early pregnancy, because the neural tube closes 3 to 4 weeks after conception, often before a woman knows she is pregnant. Anyone who could become pregnant should discuss folic acid with a doctor.^[1]
• Women who have had a pregnancy affected by a neural tube defect may be advised to take much higher doses, which exceed the upper limit and must be taken only under medical supervision.^[1]

Kidney and liver cautions

• Heavy alcohol use reduces folate absorption and how the liver takes it up. People with liver or kidney disease should ask their doctor before using folic acid supplements.^[1]

Upper intake limits

When to talk to a professional

Talk to a doctor or registered dietitian before starting a supplement, especially if you are pregnant or breastfeeding, have a long-term illness, or take any regular medicines.

Do not start, stop or change a prescribed medicine because of anything you read here.

Supplements sold without a prescription are not automatically safe. Doses, quality and interactions still matter.

Seek medical care promptly if you have severe, sudden or worsening symptoms.

If you are planning a pregnancy, ask your doctor about folic acid before you conceive.

Still being verified

• ICMR-NIN 2020 values for pregnancy/lactation and Tolerable Upper Limit not verified; not stated.
• Indian periconceptional folic acid programme guidance not yet verified; not stated.

References

1. NIH Office of Dietary Supplements. Folate — Fact Sheet for Health Professionals (opens in a new tab) (2022-11-30). Accessed 9 Oct 2026.
2. ICMR-National Institute of Nutrition (India). A Brief Note on Nutrient Requirements for Indians, the Recommended Dietary Allowances (RDA) and the Estimated Average Requirements (EAR), ICMR-NIN, 2020 (opens in a new tab). Accessed 9 Oct 2026.

Sources checked: 9 Oct 2026