Understanding Labs & Numbers

 Your health numbers can provide valuable information about how your body is functioning. Blood pressure, blood sugar, A1C, cholesterol, and routine laboratory tests can help you and your healthcare team recognize patterns and changes over time.

Understanding these numbers doesn't mean diagnosing yourself. It means becoming a more informed participant in your own wellness journey.

When you understand what a test measures and why it matters, you can:

• Recognize changes and trends over time
• Better understand conversations with your healthcare provider
• Ask more informed questions about your health
• See how different areas of the body may be connected
• Make informed lifestyle choices that support your overall wellness

Awareness brings change. Knowing your numbers is one more way to become an active participant in your health and quality of life.

Educational information only. Laboratory results and health measurements should be interpreted by your qualified healthcare

 Laboratory tests provide information that healthcare providers use to better understand different aspects of your health. Results are usually compared with a reference range, which shows the range of values expected for that particular test in a reference population.

A result may be marked High (H) or Low (L) when it falls outside the laboratory's reference range. An abnormal or flagged result does not automatically mean that you have a health condition. Results need to be considered along with your health history, symptoms, medications, other test results, and other individual factors.

Reference ranges can also vary between laboratories because different testing methods, equipment, and populations may be used.

• Look at the reference range printed on your own laboratory report. 
• One result provides a snapshot; changes and trends over time can provide additional information. 
• Avoid comparing your numbers directly with someone else's. 
• Ask your healthcare provider about results you don't understand or results that are outside the reference range. 
• Laboratory results are one piece of your overall health picture. 

Know your numbers. Ask questions. Stay involved in your healthcare.

For educational purposes only. Laboratory results should be interpreted by a qualified healthcare provider based on your individual health history and circumstances.

Blood pressure measures the force of blood pushing against the walls of your arteries as your heart pumps blood throughout your body.

A blood pressure reading contains two numbers:

• Systolic pressure — top number: the pressure in your arteries when your heart beats.
• Diastolic pressure — bottom number: the pressure in your arteries while your heart rests between beats.
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For most adults, the American Heart Association currently defines normal blood pressure as less than 120/80 mm Hg. Blood pressure categories increase from elevated to Stage 1 and Stage 2 hypertension based on the systolic and/or diastolic readings.

One blood pressure reading is only a snapshot. Tracking readings over time can provide a more complete picture for you and your healthcare provider.

Know your numbers. Understanding what they measure can help you become a more informed participant in your healthcare.

The A1C test is a blood test that estimates your average blood glucose (blood sugar) level over approximately the past 2–3 months. Unlike a fasting glucose test, you generally do not need to fast before an A1C test. 

🟢 NORMAL
Below 5.7%

🟡 PREDIABETES
5.7% – 6.4%

🟠 DIABETES RANGE
6.5% or higher

These are diagnostic thresholds; they are not the same as an individualized A1C goal for someone who already has diabetes. A diabetes diagnosis generally requires confirmation with another abnormal test unless there are clear symptoms. Certain conditions affecting red blood cells or hemoglobin can also affect A1C accuracy

A fasting blood glucose test measures the amount of glucose (sugar) in your blood after you have not eaten or had anything to drink except water for at least 8 hours. Glucose is an important source of energy for your body's cells. 

For nonpregnant adults, the standard diagnostic ranges are:

Normal: 70–99 mg/dL
Prediabetes: 100–125 mg/dL
Diabetes range: 126 mg/dL or higher

MedlinePlus notes that laboratory reference ranges can vary slightly, and a diabetes diagnosis is generally confirmed with additional testing rather than based on a single fasting result alone. 

A fasting glucose result is a snapshot of your blood sugar at that moment, while A1C provides information about average blood glucose over the previous 2–3 months. That's why the two numbers tell you different things.

A cholesterol test, also called a lipid panel or lipid profile, measures cholesterol and other fats in your blood. These numbers help your healthcare provider evaluate your cardiovascular risk. 

For adults age 20 and older, MedlinePlus provides these general healthy/desirable levels:

Total Cholesterol: Less than 200 mg/dL

LDL (“bad” cholesterol): Less than 100 mg/dL

Lower LDL is generally better. Individual LDL goals may be lower for people with cardiovascular disease or higher cardiovascular risk.

HDL (“good” cholesterol): 60 mg/dL or higher is considered best
MedlinePlus identifies HDL below 40 mg/dL for men and below 50 mg/dL for women as low. 

Triglycerides:
Normal: Less than 150 mg/dL
Borderline high: 150–199 mg/dL
High: 200–499 mg/dL
Very high: 500 mg/dL or higher 

Total cholesterol measures the overall amount of cholesterol in your blood. LDL carries cholesterol and can contribute to plaque buildup in arteries when levels are high. HDL helps transport cholesterol back to the liver for removal. Triglycerides aren't cholesterol; they're another type of fat measured as part of the lipid panel. 

These numbers should be considered together with factors such as age, family history, blood pressure and overall cardiovascular risk. Your healthcare provider can determine what levels are appropriate for you. 

Vital signs are basic measurements that provide information about how the body is functioning. They may be checked during routine healthcare visits and can be influenced by age, activity, medications, illness, stress, environment, and other individual factors.

For a typical healthy adult at rest:

❤️ Resting Heart Rate: 60–100 beats per minute (bpm)
A well-trained athlete may normally have a resting heart rate below 60 bpm.

🫁 Respiratory Rate: 12–18 breaths per minute
This is the number of breaths taken in one minute while at rest.

🌡️ Body Temperature: approximately 97.7°F–99.1°F (36.5°C–37.3°C)
Normal temperature varies by person, time of day, activity and how the temperature is measured. An average often cited is 98.6°F (37°C).

🩸 Oxygen Saturation (SpO₂): generally 95%–100%
Pulse oximetry estimates how much oxygen the blood is carrying. Certain health conditions and higher elevations can result in lower usual readings.

 Explore Medline Plus

Vital signs provide a snapshot of basic body functions. A single measurement doesn't necessarily tell the whole story. Healthcare providers consider the measurement along with symptoms, medical history, medications, usual baseline and other clinical information.

Blood tests can provide healthcare providers with information about blood cells, metabolism, cholesterol, thyroid function, and how organs such as the kidneys and liver are functioning. Different tests measure different substances, so providers may order several tests together depending on what information they need. 

CBC — Complete Blood Count
Measures components of your blood, including red blood cells, white blood cells, platelets, hemoglobin, hematocrit, and MCV. 

CMP — Comprehensive Metabolic Panel
Measures 14 substances, including glucose, calcium, electrolytes, proteins, liver-related markers, bilirubin, BUN, and creatinine. It provides information about metabolism, fluid and electrolyte balance, and liver and kidney health. 

Lipid Panel
Measures fats in the blood, including total cholesterol, LDL, HDL, and triglycerides, and is used as part of evaluating cardiovascular risk. 

Thyroid Tests
Common thyroid blood tests include TSH, T4, and T3. Additional thyroid tests may be ordered when appropriate, such as thyroid antibody testing. 

Kidney Tests
Blood tests such as creatinine and BUN, along with other blood and urine measurements, can provide information about kidney function. Creatinine is also used when calculating eGFR, an estimate of kidney filtration. 

Liver Tests
Common liver-related measurements include ALT, AST, ALP, bilirubin, albumin, and total protein. Some of these are included in a CMP. Liver tests alone generally cannot identify the specific cause of an abnormal result. 

Important: A result outside a laboratory's reference range does not automatically mean that you have a medical condition. Healthcare providers interpret laboratory results together with your health history, symptoms, medications, other testing, and previous results. 

  When you look at laboratory results, you may see an H (High) or L (Low) next to some of your numbers. These flags show that the result falls outside the reference range used by that particular laboratory.

H — High
The result is above the laboratory's reference range.

L — Low
The result is below the laboratory's reference range.

Reference Range
A reference range is the set of values a laboratory uses to compare your result with values found in a defined reference population. Different laboratories may use different testing methods and reference ranges, so always compare your result with the range printed on your own laboratory report.

An H or L is a flag—not a diagnosis.

A healthy person can sometimes have a result outside a reference range, while a result inside the reference range doesn't always rule out a health concern. Healthcare providers interpret laboratory results in context, including your health history, symptoms, medications, other test results, and changes over time.