A/G Ratio

What it is

The A/G ratio compares albumin — the single most abundant protein in blood — against everything else lumped together as globulin. Both come off the same panel, and the ratio is calculated from them rather than measured separately. It's a crude summary of two very different things: albumin largely reflects liver production and nutritional state, while the globulin fraction moves with immune and inflammatory activity. That makes the ratio a blunt instrument — it can shift because albumin fell, because globulin rose, or both, and the number alone doesn't say which. It's most useful as a prompt to look at the two components separately, and at anything else on the panel that might explain them, rather than as a finding in itself.

Worth asking your clinician

• Does my A/G ratio add anything beyond my albumin and total protein results?