Feeling worn out, pale, or short of breath? Those are some of the common signs of folate (vitamin B9) deficiency. Folate helps make red blood cells and supports cell growth, so when levels drop your body shows it fast. This page gives clear, practical steps to spot a deficiency, what tests help, and simple treatment options you can talk over with your doctor.
Folate deficiency often causes a type of anemia called megaloblastic anemia. Expect fatigue, weakness, pale skin, a sore or smooth tongue, and trouble concentrating. Pregnant women risk serious problems: low folate can raise the chance of neural tube defects in the baby.
People more likely to be low on folate include pregnant people, heavy drinkers, those on certain medicines (like methotrexate, some anticonvulsants or sulfasalazine), and anyone with poor diet or malabsorption (celiac disease, inflammatory bowel disease). Older adults and people who have had bariatric surgery can also be at risk.
A simple blood test can flag a folate problem. Your doctor often orders a CBC first — low hemoglobin and a high mean corpuscular volume (MCV) point to megaloblastic anemia. Serum folate or red blood cell (RBC) folate tests check folate levels directly. Elevated homocysteine supports folate deficiency. A useful tip: methylmalonic acid (MMA) stays normal in folate deficiency but rises in B12 deficiency, so doctors often test B12 too. That matters because giving folic acid when someone actually lacks B12 can hide the anemia while leaving nerve damage to worsen.
Treatment is straightforward: improve intake and correct any cause. Many cases respond to oral folic acid. Typical approaches are 400–1000 mcg (0.4–1 mg) daily for mild issues; pregnant women are usually advised 600–800 mcg daily. If you’re at high risk for neural tube defects (previous baby with NTD), doctors may prescribe 4 mg (4000 mcg) before and during early pregnancy — only on medical advice.
Two common supplement forms are folic acid (synthetic) and L-methylfolate (active form). L-methylfolate can help if your body has trouble converting folic acid, but discuss this with your clinician. Try to get folate from food too: leafy greens (spinach, kale), legumes (lentils, beans), citrus fruits, and fortified cereals are good sources. Cut back on heavy alcohol use and manage interacting medications with your prescriber.
If you notice persistent fatigue, unexplained pallor, or are planning pregnancy, check with your doctor. They’ll sort tests, look for causes, and suggest the right dose — and they’ll decide if B12 tests or combined treatment are needed. Small steps—diet, targeted supplements, and proper testing—fix most folate problems quickly.
