Vitamin A deficiency diagnosis:
Vitamin A levels are measured by tests for retinol. Usually the 30-60 mg/dl retinol concentrations of bold-serum are believed to be within the normal range. Vitamin A levels below that range suggest vitamin A deficiency.
Also, plasma levels of retinol can be measured. If vitamin A deficiency is advanced the plasma levels of retinol are below the usual 28 to 86 μg/dL (1 to 3 µmol/L).
We can measure night blindness by electroretinography. Other illnesses connected with vitamin A deficiency, such as keratinomalacia are diagnosed by trained medical personnel.
See also: Vitamin A overview, Vitamin A deficiency description, Vitamin A deficiency causes and symptoms, Vitamin A deficiency treatment, Vitamin A deficiency prevention