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Lab Testing, Explained
Evidence-based guides across every major testing category. No jargon, no sales pitch — just the science.
Looking up a specific term? See the glossary →
CRP and hsCRP: The Inflammation Marker Your Standard Blood Panel Might Skip
C-Reactive Protein (CRP) is one of the most sensitive acute-phase reactants in your blood — it rises fast when inflammation is present. High-sensitivity CRP (hsCRP) is the same test, but measured with enough precision to detect the low-grade chronic inflammation that standard CRP assays miss. It is now recommended as a cardiovascular risk modifier by the American Heart Association and the 2026 ACC/AHA dyslipidemia guideline — and it is one of the most useful single numbers you can add to a standard wellness panel.
Lp(a): The Cholesterol Number Your Standard Panel Completely Misses
Your doctor probably has not ordered this test — and there is a chance the 2026 ACC/AHA guidelines will change that. Lp(a) is one of the most potent, genetically determined cardiovascular risk factors we know how to measure, and it is not on your standard lipid panel.
Thyroid Function Tests Explained: TSH, T4, T3, and Antibodies
TSH, Free T4, Free T3, TPO, TgAb — what each test measures and why "subclinical" thyroid dysfunction matters.
Understanding Your Lipid Panel: LDL, HDL, Triglycerides, and Beyond
Cholesterol is more nuanced than LDL vs. HDL. This guide covers particle size, ApoB, Lp(a), and what your numbers actually tell you.
Complete Guide to Blood Panel Tests: What to Ask Your Doctor
A walkthrough of every standard blood panel — CBC, CMP, lipid panel, thyroid panel — with the exact questions to ask your provider.
Why Your Cholesterol Test Is Missing the Most Important Number
Your standard lipid panel tells you your LDL cholesterol. It does not tell you how many LDL particles are actually floating through your bloodstream. That number — apolipoprotein B, or ApoB — is what the 2026 ACC/AHA guidelines now specifically recommend for millions of Americans whose LDL looks fine but whose cardiovascular risk is not.
Vitamin D Testing: What 25(OH)D Actually Tells You
If your doctor ordered a "vitamin D test," there is a roughly 50% chance they checked the wrong metabolite — or ordered a test you did not need in the first place. Here is what the numbers mean — without the hype.