Laboratory test · Men’s health
Folic Acid
- Sample: venous blood
- Preparation: fasting not essential
Test price
- Sample
- venous blood
- Preparation
- fasting not essential
Paymentcash, cards and instalments
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This test measures serum folate (folic acid, vitamin B9). A doctor requests it for suspected folate deficiency, most often when a blood count shows anaemia with enlarged red blood cells, with poor nutrition or conditions impairing nutrient absorption, usually alongside vitamin B12.
Who the test is for
- people with anaemia and enlarged red blood cells (high MCV in a complete blood count), with fatigue, pallor, breathlessness or a sore, red tongue;
- people with a limited diet low in vegetables and those who drink excessive alcohol;
- people with conditions impairing nutrient absorption, such as coeliac or inflammatory bowel disease, and after bowel surgery;
- people with increased requirements, for example during pregnancy and breastfeeding, with haemolytic anaemia or on dialysis;
- people taking long-term medicines affecting folate, such as methotrexate, some epilepsy medicines or sulfasalazine.
What folic acid is and why it matters
Folates are B vitamins naturally found in green leafy vegetables, legumes, citrus fruit and liver; folic acid is the form in supplements and fortified foods. They are needed for DNA production and cell division, so rapidly renewing tissues need them most, such as bone marrow where red blood cells form.
Folates work together with vitamin B12. Both are needed to break down the amino acid homocysteine, so deficiency of either raises blood homocysteine. Body folate stores last only a few months, so deficiency can develop relatively quickly when intake or absorption declines.
Folic acid before and during pregnancy
Enough folic acid early in pregnancy reduces the risk of fetal neural tube defects such as spina bifida. The neural tube closes in the first weeks, often before a woman knows she is pregnant. All women planning pregnancy are therefore advised to take 400 micrograms of folic acid daily from before conception until the end of week 12 of pregnancy.
No blood test is needed for this supplement, and a normal result does not replace it. For higher-risk women, for example after a pregnancy affected by a neural tube defect, with diabetes or taking epilepsy medicines, a doctor may prescribe a higher dose. Folate testing in pregnancy is useful when a doctor suspects deficiency, for example in anaemia.
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Test Folic acid is also included in these panels.
Preparation and sample
Blood is taken from a vein. Fasting is not essential for this test alone, but if glucose, lipids or PT are measured from the same sample, come in the morning after fasting. Tell your doctor about folic acid or B-vitamin supplements because a recent supplement temporarily raises serum folate. If you take biotin (e.g. hair and nail supplements), mention it at sampling. When investigating anaemia, blood is best taken before starting replacement.
How results are interpreted
The reference interval depends on the method and is printed on the report. Serum folate mainly reflects recent intake, so even a brief period of poor nutrition can cause a low value. A doctor therefore interprets results alongside blood count, vitamin B12 and symptoms.
- Low folic acid suggests deficiency due to poor intake, alcohol, reduced absorption, increased requirements or medicines. With an inconclusive result, a doctor may measure homocysteine or request other tests.
- High folic acid most often results from supplements or fortified foods and is usually not a cause for concern alone.
Folic acid and vitamin B12 are also interpreted together for treatment safety. Folic acid can improve the blood count even with vitamin B12 deficiency, but does not prevent the nerve damage it causes. A doctor therefore checks B12 before folic acid replacement.
How to arrange testing
You can have blood taken without an appointment or referral at one of our branches across Croatia (listed on the Contact page). Prices for all tests and panels are available in the service price list. Folic acid is most often measured alongside vitamin B12 and a complete blood count.
Frequently asked questions
Should I have folic acid tested before pregnancy?
Testing is not required to take the 400 micrograms of folic acid daily recommended for all women planning pregnancy. A doctor may recommend it if deficiency is suspected, for example with anaemia, bowel disease or medicines affecting folate.
What does low folic acid mean?
Most often inadequate folate intake or reduced absorption. If the blood count is also abnormal or symptoms are present, a doctor investigates the cause and checks vitamin B12 before starting replacement.
What is the difference between folate and folic acid?
Folate is the natural form of vitamin B9 in food; folic acid is the form in supplements and fortified foods. The test measures total blood folate regardless of its source.
Can folic acid be too high?
High results most often reflect supplements. Usually not dangerous alone, high folic acid doses can mask vitamin B12 deficiency, so the replacement dose should be agreed with a doctor.