What Biomarkers Should You Test Annually?
Most annual physicals include a handful of basic blood tests. Your doctor orders a CBC, a metabolic panel, maybe a lipid panel, and calls it a day. But if you are serious about preventing chronic disease rather than just detecting it after it arrives, you need a much more comprehensive picture of what is happening inside your body.
Here are the biomarkers that actually matter for long-term health, organized from essential basics to advanced markers that most doctors never order.
The Basics Everyone Should Test
These are the foundational markers. If you are only going to get one blood panel per year, make sure it includes these.
A Complete Blood Count (CBC) measures your red blood cells, white blood cells, hemoglobin, hematocrit, and platelets. It is the most basic overview of your blood health and can flag issues ranging from anemia to infection to blood cancers. Every annual physical should include this.
A Comprehensive Metabolic Panel (CMP) covers 14 measurements including glucose, kidney function markers like BUN and creatinine, liver enzymes like ALT and AST, electrolytes, and protein levels. This gives you a snapshot of your metabolic health, organ function, and hydration status.
A Lipid Panel measures total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides. These numbers are used to estimate cardiovascular risk, though as we will discuss below, standard lipid panels miss critical information.
Hemoglobin A1C reflects your average blood sugar over the past two to three months. It is the gold standard for diabetes screening and monitoring. An A1C below 5.7 is considered normal, 5.7 to 6.4 is prediabetic, and 6.5 or above indicates diabetes. Nearly 40 percent of American adults are prediabetic, and most do not know it.
Thyroid Stimulating Hormone (TSH) screens for thyroid dysfunction. However, TSH alone is not enough. If your TSH is borderline or you have symptoms of thyroid issues, you need a full thyroid panel including Free T3, Free T4, and thyroid antibodies (TPO and thyroglobulin antibodies).
Advanced Markers for Deeper Insights
This is where testing gets genuinely predictive rather than just diagnostic. These markers can identify risk years or decades before disease develops.
Apolipoprotein B (ApoB) is arguably the single most important cardiovascular marker that most people have never heard of. While standard LDL cholesterol measures the amount of cholesterol inside LDL particles, ApoB counts the actual number of atherogenic particles in your blood. Research consistently shows that ApoB is a better predictor of heart attack and stroke risk than LDL-C. An optimal ApoB level is below 80 mg/dL, and ideally below 60 mg/dL for people at higher risk.
Lipoprotein(a), or Lp(a), is a genetically determined lipoprotein that dramatically increases cardiovascular risk in roughly one in five people. Unlike LDL, Lp(a) levels are almost entirely determined by your genes and do not respond to diet or exercise. You only need to test it once in your lifetime to know your level, but most people have never been tested. If your Lp(a) is elevated, you and your doctor can take more aggressive preventive action on other modifiable risk factors.
Fasting Insulin is perhaps the most underutilized marker in preventive medicine. Blood glucose and A1C only become abnormal after your body has been struggling with insulin resistance for years. Fasting insulin rises much earlier, often five to ten years before glucose starts climbing. An optimal fasting insulin level is below 5 uIU/mL. If yours is above 8 to 10, you likely have early insulin resistance that diet and exercise changes can still reverse.
The Omega-3 Index measures the percentage of EPA and DHA in your red blood cell membranes. An index above 8 percent is associated with significantly lower risk of cardiovascular disease, cognitive decline, and depression. Most Americans have an index between 4 and 5 percent, well below the optimal range. This test tells you whether your omega-3 supplementation or fish consumption is actually working.
High-Sensitivity C-Reactive Protein (hs-CRP) measures systemic inflammation. Chronic low-grade inflammation is now understood to be a root driver of heart disease, cancer, diabetes, and neurodegenerative disease. An hs-CRP below 1.0 mg/L is ideal. Between 1.0 and 3.0 indicates moderate risk, and above 3.0 suggests high inflammatory burden that needs to be addressed.
Hormone and Nutrient Markers
Vitamin D levels should be tested at least annually. Deficiency is extremely common, affecting an estimated 40 percent of Americans. Optimal levels are between 40 and 60 ng/mL, though many labs still use an outdated reference range that considers anything above 30 as normal. Low vitamin D is associated with increased risk of osteoporosis, immune dysfunction, depression, and certain cancers.
Ferritin measures your iron stores. Both low and high ferritin can be problematic. Low ferritin (below 30 ng/mL) causes fatigue, brain fog, and exercise intolerance even when your hemoglobin is technically normal. Elevated ferritin (above 200 in women, above 300 in men) can indicate iron overload, inflammation, or liver disease.
For men over 30, testosterone including both total and free testosterone should be part of annual testing. Testosterone levels have been declining across generations, and low testosterone affects energy, mood, body composition, and metabolic health. For women, testing estradiol, progesterone, and DHEA-S provides important information about hormonal balance, especially around perimenopause.
Why Standard Panels Miss Critical Markers
The standard annual blood panel was designed decades ago for disease detection, not disease prevention. Insurance companies will typically cover a CBC, CMP, lipid panel, and A1C. They may cover TSH if you have symptoms. But they routinely deny coverage for ApoB, Lp(a), fasting insulin, omega-3 index, and many other markers that research has shown to be critical for early risk detection.
The reason is simple: insurance operates on a sick-care model. Tests are covered when there is a clinical indication, meaning you already have symptoms or a diagnosis. Truly preventive testing, the kind that catches problems five or ten years before symptoms appear, is often classified as not medically necessary.
This is the gap that comprehensive testing services are designed to fill.
How Function Health Covers All of These
Function Health includes over 100 biomarker tests in its annual membership, and every marker discussed in this article is included. ApoB, Lp(a), fasting insulin, omega-3 index, hs-CRP, a full thyroid panel, vitamin D, ferritin, hormone panels, and dozens more are all part of the standard package.
You get tested twice per year at Quest Diagnostics locations, and results are delivered through a dashboard that tracks your trends over time. At $499 per year (currently $365 with membership pricing), the per-test cost is a fraction of what you would pay ordering these tests individually, with or without insurance.
Building Your Annual Testing Protocol
If you are designing your own annual testing protocol, here is a practical framework. At minimum, get a CBC, CMP, lipid panel, A1C, and TSH every year. Add ApoB and hs-CRP for cardiovascular and inflammation monitoring. Test fasting insulin to catch metabolic dysfunction early. Check vitamin D and ferritin to optimize energy and immune function. Test Lp(a) at least once. And if budget allows, add an omega-3 index and hormone panel.
The goal is not to run as many tests as possible. The goal is to measure the markers that give you actionable information, the ones that tell you something you can actually change before it becomes a serious problem. Preventive testing is the most cost-effective healthcare investment you can make.