What Your Blood Test Results May Reveal About Health

A routine blood test can reveal important information about your health. Internal Medicine expert Justin Yadegar, MD, explains what providers look for — and why you should always consider your results in context.

If you have visited your primary care provider for an annual checkup, you may have been asked to have blood drawn. Laboratory testing can provide a valuable snapshot of your overall health, help identify potential concerns, and give your provider information to guide follow-up care.

“Blood tests can help us evaluate how organs such as the kidneys and liver are functioning and begin to identify potential health issues,” says Dr. Yadegar. “They can also help us monitor certain conditions and determine whether medications are working as intended.”

One commonly ordered blood test is a metabolic panel. A basic metabolic panel generally measures glucose, calcium, electrolytes, and kidney function indicators. A comprehensive metabolic panel includes those measurements as well as proteins and substances associated with liver function.

Numbers your provider may review

Blood glucose

Glucose is your body’s primary energy source. A higher-than-expected blood glucose level may be associated with prediabetes or diabetes. However, factors such as eating before the test, stress, illness, and certain medications can also affect the result.

Low blood glucose is more common among people who take insulin or certain diabetes medications. Your provider may review your eating patterns, medications, and other factors to determine whether changes are needed.

A single glucose result does not necessarily confirm diabetes. Depending on the result, your provider may recommend additional testing, such as an A1C or fasting blood glucose test.

Kidney function

Your kidneys filter waste and excess fluid from your blood. A metabolic panel commonly measures creatinine and blood urea nitrogen, or BUN, to help assess how well they are working.

Elevated levels may signal reduced kidney function, but dehydration, medications, diet, and other health factors can also affect them. Creatinine may also be used to calculate an estimated glomerular filtration rate, or eGFR, which helps assess how effectively the kidneys are filtering blood.

“We look at the complete picture rather than relying on one number,” says Family Medicine specialist Sami Daher, DO. “An unexpected result may simply mean that we need to repeat the test or gather more information.”

Liver function

A comprehensive metabolic panel measures several substances associated with liver health, including enzymes, proteins, and bilirubin.

Bilirubin is a yellowish waste product produced as the body breaks down red blood cells. Elevated bilirubin may indicate a liver condition or a blockage affecting bile flow. Abnormal liver enzyme levels may also indicate inflammation, injury, or another condition requiring further evaluation.

Because medications, alcohol use, recent illness and other factors can affect these measurements, your provider will interpret them in the context of your overall health.

Electrolytes

Electrolytes — including sodium, potassium, chloride and bicarbonate — help regulate fluid balance, muscle and nerve function, blood pressure and heart rhythm.

“Electrolyte levels can tell us a great deal about how the body is maintaining its internal balance,” Dr. Yadegar. “Abnormal levels may be related to hydration, medications, or an underlying health condition.”

Significant electrolyte imbalances can sometimes require prompt attention, but a mildly abnormal result may have several possible explanations. Your provider can determine whether follow-up testing or treatment is appropriate.

Understanding your results

Laboratory reports typically display a reference range next to each result. These ranges can vary slightly among laboratories and may differ based on factors such as age, sex, and testing method.

A result outside the listed range does not necessarily mean something is wrong. Likewise, a result within the reference range does not always rule out a health concern. Your provider will consider your results alongside your symptoms, health history, medications and previous test results.

Before having blood drawn, ask whether you need to fast or make any temporary changes to medications or supplements. Do not stop taking prescribed medication unless your provider specifically instructs you to do so.

Schedule your checkup

Routine primary care visits can help you understand your health, identify potential concerns early, and stay current with recommended screenings.

Find an Adventist Health Simi Valley primary care provider or schedule an appointment near you.