The Folate test is a blood test that measures the level of folate, also known as Vitamin B9, in the blood. Folate is a water-soluble B vitamin that the body cannot synthesise on its own and must obtain entirely from dietary sources including green leafy vegetables, legumes, citrus fruits, eggs, and fortified cereals. The synthetic form of folate used in supplements and food fortification is known as folic acid. Folate plays an indispensable role in DNA synthesis, cell division, red blood cell formation, and the metabolism of homocysteine, an amino acid whose elevated levels are independently associated with cardiovascular disease and stroke.
The serum folate test reflects recent dietary folate intake over the preceding days to weeks, while a red blood cell folate test, where available, reflects longer-term folate status over the preceding two to three months. Together, these measurements provide a comprehensive picture of folate nutritional status. In India, folate deficiency is one of the most prevalent nutritional deficiencies, driven by inadequate dietary intake, overcooking of vegetables which destroys folate content, widespread poverty limiting dietary diversity, and high physiological demands during pregnancy and lactation.
Folate deficiency causes megaloblastic anaemia, a condition in which red blood cells become abnormally large and dysfunctional, impairing oxygen delivery throughout the body. Most critically, folate deficiency in early pregnancy is a well-established cause of neural tube defects including spina bifida and anencephaly in the developing foetus. The test is performed on a small blood sample drawn from a vein and completed in under five minutes.