What is Albumin?

Because the liver is the only source, the amount of albumin in blood is read as a measure of the liver's protein output. Inflammation elsewhere in the body complicates that reading: the liver switches towards making inflammatory proteins such as CRP, and albumin falls while the liver is working normally. hs-CRP measures that inflammation, so reading it beside albumin separates an inflammatory fall from a liver one.

Albumin and Globulin are the two fractions that add up to Total Protein, and albumin is the larger of them, so the total follows albumin more closely than globulin. eGFR and Creatinine estimate how well the kidneys are filtering, so a kidney reading that has moved as well points to albumin lost in urine rather than albumin the liver never made.

The liver's capacity to make protein falls in long-standing liver disease, and the albumin supply falls with it. Loss is the other route: protein escapes through damaged kidneys or an inflamed gut. Extra fluid in the blood lowers the figure a third way, by dilution, without any albumin being lost at all.

Albumin circulates for around three weeks before it is broken down, so the amount the liver makes changes slowly. The level in a blood sample can still shift within hours: dehydration concentrates it, extra fluid dilutes it, and acute illness draws it out of the blood vessels into the tissues. A yearly measurement taken while someone is well reads the liver's protein output and any ongoing loss. This is Do Health's monitoring schedule, not a general recommendation for everyone.