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Cheapest test that includes it£495.00Vitamin Basic Screen at Better2Know, all-in with a vein draw
Tests compared3from 1 provider, checked 29 October 2026
What it measures
The test measures riboflavin, vitamin B2, usually as its active form FAD in whole blood. Some labs instead use a red cell enzyme test that shows riboflavin status indirectly.
Why people test it
Measured when low intake is suspected, for example with a restricted diet, heavy alcohol use or poor absorption.
Part of some nutrition panels covering the B vitamins.
Typical range
Ranges vary by lab, method, age and sex, and your report shows the lab's own range.
Finger-prick or vein?
Taken from a vein, and providers offer it only as a vein draw. Riboflavin breaks down in light, so samples are kept away from light.
Every Vitamin B2 test, cheapest first
Cheapest first, whether the test is of Vitamin B2 alone (marked "single-marker test") or a panel that includes it. Each price is all-in: the test and the cheapest way to have the blood taken that suits this marker, before any discount code.
Cheapest per doseBest value under 6 months' supplyRiboflavin · 60 capsules · 60 servings · 400 mg a servingDetails and price history →claimed: veganHPMC capsule, the listing says
· 60 capsules · 60 servings · 400 mg a serving