Blood cells: the CBC
A complete blood count measures red cells, white cells and platelets, along with features such as hemoglobin and the average size of red blood cells. Hemoglobin carries oxygen; white cells help fight infection; platelets help blood clot.[1]
These results can help investigate anemia or changes in blood cell counts. Interpretation depends on the pattern and your history. An out-of-range result can also be influenced by factors such as hydration, medication use or menstruation.[1]
Chemistry: the metabolic panel
A comprehensive metabolic panel includes glucose, electrolytes, proteins and measurements related to liver and kidney health. For example, creatinine is a waste product filtered by the kidneys, while ALT and AST are enzymes considered in liver assessment.[2]
The results are read together. One unusual number can point toward a follow-up question, but it often takes additional information or testing to establish a diagnosis.[2]
Blood fats: the lipid panel
A lipid panel usually reports LDL cholesterol, HDL cholesterol, total cholesterol and triglycerides. It contributes to an assessment of cardiovascular risk, alongside information such as blood pressure, smoking and family history.[3]
What does the red flag mean?
The flag usually means a result is outside that laboratory's reference range. Healthy people can sometimes have results outside those ranges, and a result inside the range does not rule out every illness. Different labs may also use different methods and ranges.[4]
The most useful explanation of a report connects the finding to a next step: whether it changes a decision, needs confirmation, or simply provides a comparison for later. Keep the complete report, including units, reference ranges and date, so future comparisons use the same information.[4]
