The Complete Blood Panel Glossary

A protein made by your liver that circulates in your blood, albumin helps maintain fluid balance and transport hormones, vitamins, and medications throughout your body. Low levels can signal liver disease, kidney problems, or chronic inflammation, while very high levels often point to dehydration. Normal range is 3.5–5.5 g/dL.

ApoB is a protein found on the surface of all atherogenic lipoproteins — the particles that cause arterial plaque. Each potentially harmful particle carries exactly one ApoB molecule, making it a more accurate measure of cardiovascular risk than LDL-C alone. Optimal level is below 90 mg/dL for most men, below 60 mg/dL for high-risk individuals.

BUN measures the amount of urea nitrogen in your blood — a waste product your kidneys filter out. Elevated levels can indicate kidney dysfunction, dehydration, or a high-protein diet, while very low levels may suggest liver disease. Normal range is 7–20 mg/dL, and the BUN-to-creatinine ratio provides additional diagnostic context.

The CBC is the most commonly ordered blood test, measuring red blood cells, white blood cells, hemoglobin, hematocrit, and platelets. It screens for anemia, infection, clotting disorders, and blood cancers in a single panel. This is the foundational test every man should get annually — it reveals more than most people realize.

Creatinine is a waste product from normal muscle metabolism that your kidneys filter out of the blood. Elevated levels suggest reduced kidney function, though muscular men may naturally run slightly higher. Normal range for men is 0.7–1.3 mg/dL, and this number is used to calculate your GFR — the gold standard for kidney health assessment.

CRP is produced by your liver in response to inflammation anywhere in the body. Chronically elevated CRP is linked to increased cardiovascular risk, metabolic syndrome, and autoimmune conditions. The high-sensitivity version (hs-CRP) detects subtle inflammation: below 1.0 mg/L is low risk, 1.0–3.0 is moderate, and above 3.0 signals high cardiovascular risk.

eGFR is a calculated estimate of how well your kidneys filter blood, derived from your creatinine level, age, and sex. A result below 60 mL/min/1.73m² indicates chronic kidney disease and requires further evaluation. Values above 90 are considered normal, though eGFR naturally declines with age — tracking the trend matters more than any single result.

GFR is the gold standard measurement of kidney function, representing how many milliliters of blood your kidneys filter per minute. A GFR below 60 for three months or more indicates chronic kidney disease, while below 15 means kidney failure. Most labs report estimated GFR (eGFR) calculated from creatinine, age, and body metrics.

HDL is the "good" cholesterol that carries excess cholesterol from your arteries back to your liver for disposal, protecting against plaque buildup. For men, levels above 40 mg/dL are acceptable but 60 mg/dL or higher is considered protective against heart disease. Regular exercise, moderate alcohol, and healthy fats are the most effective ways to raise HDL naturally.

A1C measures the percentage of hemoglobin coated with sugar, reflecting your average blood glucose over the past 2–3 months. Below 5.7% is normal, 5.7–6.4% indicates prediabetes, and 6.5% or higher signals diabetes. This is arguably the most important metabolic marker for men over 40 — it reveals blood sugar problems years before symptoms appear.

hs-CRP is a refined version of the CRP test that detects very low levels of inflammation — the kind associated with cardiovascular disease rather than acute infection. Levels below 1.0 mg/L indicate low cardiovascular risk, 1.0–3.0 mg/L is moderate, and above 3.0 mg/L is high risk. Many cardiologists now consider it essential alongside the standard lipid panel.

Homocysteine is an amino acid that, at elevated levels, damages blood vessel walls and increases the risk of heart attack, stroke, and blood clots. High levels often indicate a deficiency in folate, vitamin B12, or vitamin B6. Optimal level is below 8 µmol/L, with normal range extending to 15 µmol/L — but many longevity-focused physicians target the lower end.

LDL is the "bad" cholesterol that deposits fatty plaque inside your artery walls, narrowing them over time and raising heart attack and stroke risk. Standard guidelines target below 100 mg/dL for healthy men, but many cardiologists now advocate for levels below 70 mg/dL — especially if you have additional risk factors like family history, smoking, or elevated ApoB.

Lp(a) is a genetic variant of LDL cholesterol that independently increases your risk of heart attack, stroke, and aortic valve disease. Unlike LDL, Lp(a) levels are largely determined by genetics and don't respond to statins or lifestyle changes. Every man should have this tested once in adulthood — under 30 mg/dL is optimal, above 50 mg/dL is high risk.

Platelets are small cell fragments that help your blood clot to stop bleeding after injury. A CBC measures your platelet count, with normal range between 150,000 and 400,000 per microliter. Low counts increase bleeding and bruising risk, while very high counts may indicate bone marrow disorders, chronic inflammation, or increased clotting risk.

PSA is a protein produced by the prostate gland, measured via blood test to screen for prostate cancer. The USPSTF recommends individualized screening decisions for men 55–69, though many urologists recommend a baseline test in your 40s. Levels above 4.0 ng/mL typically prompt further investigation — but BPH, prostatitis, and even recent exercise can elevate PSA without cancer being present.

Red blood cells carry oxygen from your lungs to every tissue, and hemoglobin is the protein inside them that binds that oxygen. Low levels indicate anemia (often from iron deficiency or chronic disease), while high levels may suggest polycythemia — thick blood that raises clot risk. Normal hemoglobin for men is 13.5–17.5 g/dL; anything outside this range warrants investigation.

Testosterone is the primary male sex hormone driving muscle mass, bone density, libido, red blood cell production, and mood. Total testosterone below 300 ng/dL is clinically low, causing fatigue, decreased libido, and muscle loss. Free testosterone — the unbound, bioavailable fraction — is equally important and often overlooked. Levels decline roughly 1% per year after age 30.

Triglycerides are the most common type of fat in your blood, derived from excess calories — especially sugar, refined carbs, and alcohol. Levels below 150 mg/dL are normal, but optimal is under 100 mg/dL. Elevated triglycerides increase cardiovascular risk significantly when combined with low HDL and high blood sugar — a combination known as atherogenic dyslipidemia.

Total protein measures the combined amount of albumin and globulin in your blood — reflecting liver function, nutritional status, and immune activity. Normal range is 6.0–8.3 g/dL. Low levels may indicate liver disease, kidney disease, or malnutrition, while high levels can suggest chronic infection or inflammatory conditions like multiple myeloma.

TSH is the frontline screening test for thyroid function, measuring the signal your pituitary sends to your thyroid gland. Normal range is 0.4–4.0 mIU/L, but many functional medicine practitioners consider 1.0–2.5 mIU/L optimal. High TSH suggests hypothyroidism (fatigue, weight gain, brain fog), while low TSH may indicate hyperthyroidism (anxiety, rapid heart rate, weight loss).

Uric acid is a waste product formed when your body breaks down purines — substances found in red meat, organ meats, and beer. Elevated levels can crystallize in joints causing gout, and chronically high uric acid is associated with kidney stones, metabolic syndrome, and cardiovascular disease. Normal range for men is 3.4–7.0 mg/dL; keeping it below 6.0 reduces gout risk substantially.

VLDL (Very Low-Density Lipoprotein) carries triglycerides from your liver to your tissues and is considered atherogenic — meaning it contributes to arterial plaque formation. Normal VLDL is 2–30 mg/dL, and it's typically calculated from your triglyceride value rather than measured directly. High VLDL signals poor metabolic health and is often the first lipoprotein to rise when diet deteriorates.

WBC counts your white blood cells — the immune system's front-line soldiers that fight infection and inflammation. Normal range is 4,500–11,000 cells per microliter. High WBC can signal active infection, chronic inflammation, or rarely blood cancers, while low WBC may indicate immune suppression, bone marrow problems, or certain autoimmune conditions.