: Vitamin A (Retinol) Measurement

: What Is Being Measured

: Vitamin A is a fat-soluble nutrient that exists in the body mainly as retinol. This test estimates the concentration of vitamin A in the collected sample. Because the exact specimen and measurement method are not fully specified in the test code, your laboratory report should be reviewed to confirm what type of sample was used.

: Why the Test Is Ordered

: Your healthcare provider may order a vitamin A test if you have symptoms that suggest a deficiency, such as night blindness, dry eyes, or frequent infections, or if you have a condition that affects how your body absorbs fat. It may also be used when too much vitamin A is a concern, such as with high-dose supplement use.

: How to Prepare

: Preparation depends on the type of sample being collected. Ask your provider or lab whether you need to fast or make any other changes before the test. Do not start or stop vitamin supplements on your own without discussing it with your provider, since supplements can affect results.

: Understanding Your Results

: Your result is interpreted alongside your symptoms, medical history, diet, and other tests. Levels outside the expected range can point to a deficiency or excess, but results alone do not diagnose a condition. Your provider will explain what your specific result means, and no single number applies to everyone.