Folate

What it is

Folate is a B vitamin your body uses to build DNA and make red blood cells, and serum folate measures what's circulating right now. Because it responds quickly to what you've eaten in recent days, a single value is more of a short-term snapshot than a picture of your stores — red-cell folate is sometimes used when a longer-term view is wanted, though it has its own limitations. It's usually read alongside vitamin B12 and a blood count, partly because folate and B12 findings can influence how each other are interpreted.

Typical range

Reference ranges vary between laboratories, and what is normal for you depends on your own history. Your own lab’s range is the one printed on your report.

Worth asking your clinician

• Does what I ate in the days before this draw affect how you'd read my folate?
• Would a red-cell folate or looking at this alongside my B12 give a clearer picture in my case?
• Is this a result worth rechecking, or is one value enough here?