A biomarker is a measurable substance, characteristic, or biological process that can provide information about health or disease. Blood tests can measure biomarkers such as cholesterol, glucose, and C-reactive protein (CRP). Different biomarkers provide information about different aspects of health.

What Does an A1C Test Tell You?

An A1C test measures average blood sugar levels over approximately the previous 2 to 3 months. It is used to screen for and diagnose prediabetes and diabetes and to monitor blood sugar control in people with diabetes. An A1C below 5.7% is generally considered normal, 5.7% to 6.4% indicates prediabetes, and 6.5% or higher is in the diabetes range when used for diagnosis.

What Does an Insulin Blood Test Tell You?

An insulin blood test measures the amount of insulin in the blood. Depending on the circumstances and other test results, insulin measurements can help healthcare professionals evaluate blood sugar regulation and investigate conditions such as insulin resistance or abnormal blood sugar levels. Insulin results need to be interpreted in context because a single insulin measurement does not diagnose a condition by itself.

What Getting Your Blood Work Done Can Tell You About Your Health

Q: What Does a Blood Test Tell You About Your Health?

Blood tests can provide information about blood cells, blood sugar, cholesterol, enzymes, electrolytes, hormones, nutrients, and organ function. They can help identify signs of certain health conditions, monitor existing conditions, and assess how the body is functioning. Blood-test results should be interpreted together with symptoms, medical history, and other clinical information.

Q: What Would a Complete Blood Count (CBC) Test Show?

A complete blood count (CBC) measures the number and characteristics of red blood cells, white blood cells, and platelets. Abnormal results can provide clues about conditions such as anemia, infection, inflammation, immune disorders, or some blood and bone marrow disorders. A CBC result alone does not establish a diagnosis.

Q: Can Biomarkers Change Over Time?

Yes. Biomarker levels can change over time because of factors such as aging, illness, changes in health, medications, treatments, lifestyle, and other biological factors. Tracking results over time can help healthcare professionals evaluate changes in a person's health.

Q: What Can Blood Tests Tell You About Thyroid Health?

Blood tests can measure thyroid-related hormones such as thyroid-stimulating hormone (TSH) and thyroxine (T4). These results can help healthcare professionals evaluate thyroid function and identify patterns consistent with conditions such as hypothyroidism or hyperthyroidism. Triiodothyronine (T3) may also be measured in certain circumstances.

Q: What Can Blood Tests Tell You About Your Pancreas?

Blood tests can measure enzymes such as lipase, which can provide information about pancreatic injury or inflammation. Elevated lipase levels can occur with pancreatitis, although abnormal results can have other causes and need to be interpreted with symptoms and other findings.

Q: What Can Blood Tests Tell You About Hormone Levels?

Blood tests can measure hormones such as estrogen and testosterone, as well as thyroid hormones. Abnormal hormone levels may provide clues about conditions affecting reproductive health, fertility, menopause, or other aspects of health. Hormone results need to be interpreted according to factors such as age, sex, symptoms, medications, and the timing of the test.

Q: Can Blood Tests Identify Nutrient Deficiencies?

Yes. Blood tests can help identify certain nutrient deficiencies. For example, ferritin and iron studies can help evaluate iron status, while vitamin D testing can identify low vitamin D levels. Results should be interpreted using the laboratory's reference range and the person's overall clinical situation.

A Row Of Tubes Filled With Blood For Further Testing.

Blood tests are routine medical tests. They can be ordered when you:

Exhibit symptoms of a health problem
Have a physical
Have an increased risk of developing specific health issues
Receive treatment for a health condition

While imaging tests look at physical structures inside your body, such as organs and bones, blood tests measure biomarkers and chemical levels in your blood.

Book Your Non-Invasive Scan.

What Does a Blood Test Tell You About Your Health?

What shows in a blood test can indicate if your blood is performing normally. Blood tests can also reveal issues with enzyme and electrolyte levels.

CBC Tests

What would a complete blood count (CBC) test show? A CBC provides details about the number and size of your red and white blood cells and platelets.

Tests assessing your platelet count can indicate when you may have trouble forming blood clots. Issues with your platelet count can indicate serious health issues, such as:

Tests assessing your platelet count can indicate if your blood has trouble clotting. Issues with your platelet count can indicate serious health issues, such as:

Anemia
Cancer
Crohn’s disease
Rheumatoid arthritis

Tests that assess your red blood cells can also indicate blood disorders or cancer.

White blood count tests can indicate other health issues, such as immune system diseases, infections, inflammatory diseases, and cancer.

What Is a Biomarker?

Biomarkers are measurable substances or processes. Blood tests that utilize biomarkers include the following:

Cholesterol (LDL, HDL, and ApoB) can reveal the risk of plaque buildup in your arteries. ApoB and Lipoprotein(a) are the most accurate biomarkers indicating the risk of heart disease or stroke.
C-Reactive Protein (CRP) indicates inflammation due to illness or injury.
Glucose tests can reveal if your blood sugar levels are too high or low and are used to diagnose certain conditions, such as diabetes and hypoglycemia.

Can Biomarkers Change Over Time?

Biomarkers can change. Changes may be due to aging, disease progression, or medical treatments.

What Does A1C Tell You?

An A1C test measures the average level of your blood sugar over the past few months. It can indicate that you have prediabetes or diabetes.

What Does Insulin Tell You?

A fasting insulin blood test can indicate the following issues:

Hypoglycemia
Insulin resistance
Tumor in pancreas affecting insulin production
Type 2 diabetes

What Can Blood Tests Tell You About Thyroid Health?

Measuring your thyroid-stimulating hormone (TSH) and thyroxine (T4) levels can indicate hypothyroidism or hyperthyroidism.

Additional tests measuring triiodothyronine (T3) can indicate whether your metabolism is functioning correctly.

What Can Blood Tests Tell You About Your Pancreas?

Measuring your lipase levels can indicate injury or illness affecting the pancreas, such as pancreatitis.

What Can Blood Tests Tell You About Hormone Levels?

Blood tests can reveal high or low levels of hormones that regulate thyroid function. Tests can also measure the number of other hormones, including:

Estrogen
Testosterone

These measurements may indicate fertility issues in men and women. Issues with estrogen levels can also indicate other health issues, such as menopause, liver disease, and polycystic ovary syndrome. Issues with testosterone levels may indicate erectile dysfunction, low muscle mass, or anemia.

Can Blood Tests Identify Nutrient Deficiencies?

Blood tests can reveal nutrient deficiencies.

Ferritin and iron panels can reveal an iron deficiency. A total iron-binding capacity (TIBC) test measures transferrin levels. Transferrin carries the iron through your blood. Too much transferrin can indicate low iron levels, while too little transferrin can indicate high iron levels.

A vitamin D deficiency weakens your immune system, making you more likely to get sick. It can also cause fatigue, back pain, muscle weakness and bone weakening.

What Can Blood Tests Tell You About Liver and Kidney Health?

Blood tests assessing liver health can indicate the following:

Blocked bile ducts
Liver disease
Liver inflammation
Liver injury

Blood tests assessing kidney health can indicate issues with chloride, creatinine,sodium, and potassium levels, which can indicate that the kidneys aren’t functioning properly.

How Accurate Are Blood Tests?

Blood tests are fairly accurate. However, any test can produce a false positive or false negative.

What Can Affect Blood Test Results?

Things that can affect the accuracy of your blood test results include:

Beverages
Caffeine
Dehydration
Foods
Medications
Menstruating
Strenuous exercise
Stress
Supplements
Time of test

Incorrect testing procedures can also affect test results.

Do You Need To Fast Before a Blood Test?

You will receive instructions when your blood test is scheduled. These instructions may include directions to:

Avoid excessive exercise: Don’t do any strenuous workouts for a full day before your test because exercise can affect hormone levels, blood sugar, lipids, liver enzymes, and muscle enzymes.
Drink water: Hydration levels can affect test results.
Fast: For example, if you’re having a test to check your cholesterol or lipid markers, you may need to fast for up to 12 hours.

You also should not chew gum, smoke, or take some supplements before your blood test.

What Does an Abnormal Blood Test Result Mean?

An abnormal blood test may or may not mean there’s a health problem. The result could be due to dehydration or lack of sleep. Your doctor can help determine whether your readings fall outside the typical range or indicate a health issue.

What Happens After You Receive Your Results?

You should receive results within 48 hours of your test. Talk to your doctor about the results. You may have to go for additional tests to confirm or rule out potential health issues.

What Blood Tests at Preventative Diagnostic Center Can Reveal About Your Health

Getting blood tests at Preventative Diagnostic Center can reveal critical information about your overall health. Test results may indicate issues with blood flow, nutrient deficiencies, or injuries or illnesses affecting specific organs. You can contact us to schedule a blood test.

Preventative Diagnostic Center also performs non-invasive scans.

Schedule Your Scan.

Sources:

How to Understand Your Lab Results. (2025).

Platelet Tests. (2024)

Red Blood Cell Disorders. (2026).

White Blood Count (WBC). (2024).