Why does folate deficiency cause fatigue?

Folate, also called vitamin B9, is needed to make new cells, including red blood cells. When there is too little folate, red cells may not develop normally and anaemia can result. This can leave you feeling tired, weak, light-headed, short of breath with exertion, or aware of a fast heartbeat. Fatigue is a common presentation of Folate Deficiency.

Low folate can arise from a restricted diet, reduced absorption in the gut, increased body needs, or certain medicines. Fatigue has many possible causes, so it needs assessment rather than self-diagnosis.

Book an appointment for persistent fatigue. A clinician may ask about diet, digestion, alcohol use, medicines, menstrual bleeding, pregnancy, and other symptoms, then arrange blood tests when appropriate. Do not start high-dose folic acid on your own before vitamin B12 deficiency has been considered, because folic acid can improve the blood changes while nerve problems from B12 deficiency continue.

If a deficiency is confirmed, treatment usually includes addressing the cause, food choices that provide folate, and supplements when prescribed. Take treatment as directed and attend follow-up testing if it is arranged.

Seek urgent medical care for chest pain, severe breathlessness at rest, fainting, confusion, black stools, vomiting blood, or heavy bleeding. Arrange prompt review if fatigue is rapidly worsening, you are pregnant, or you have numbness, balance changes, or memory problems.

Ask what may be causing the low folate, whether vitamin B12 and iron also need checking, which foods suit your diet, and when your symptoms and blood tests should be reviewed.