Vitamin B9

Folate; folic acid; 5-methyltetrahydrofolate

Water-soluble vitamins

Aliases / common names

Folate; folic acid; 5-MTHF; methylfolate

Natural food sources

Leafy greens, legumes, asparagus, avocado, citrus and fortified grains.

Main wellness functions

Supports DNA synthesis, red blood cell formation, methylation and fetal neural-tube development.

Deficiency signs

Megaloblastic anemia, fatigue, glossitis, elevated homocysteine and neural-tube defect risk in pregnancy.

Recommended intake

Adults: 400 mcg DFE/day. Children: about 150-400 mcg DFE/day. Pregnancy: 600 mcg DFE/day. Adult UL: 1,000 mcg/day synthetic folic acid from supplements/fortified foods.

Excess intake effects

High folic acid intake can mask vitamin B12 deficiency and may complicate neurologic assessment.

Contraindicated / caution groups

People with suspected B12 deficiency, cancer therapy, anti-seizure drugs or methotrexate should seek clinical advice.

Common dosage forms

Tablets, capsules, prenatal vitamins, folic acid, folinic acid and methylfolate.

Common product strengths

400 mcg, 800 mcg, 1 mg; prenatal products commonly provide 400-800 mcg folic acid or DFE-equivalent folate.

Use precautions

Pregnancy planning usually requires folic acid before conception; coordinate with prenatal care.

Supplement notes

DFE accounts for higher bioavailability of synthetic folic acid compared with natural food folate.

This information is for general nutrition education and product reference only. It does not replace medical diagnosis, treatment or individualized dietary advice.