The metabolic panel, and why there are three of them

Ask for a "metabolic panel" and you might get any of three things. A hospital means the basic metabolic panel, eight tests run in minutes to check fluids, electrolytes and kidney function. A GP's annual bloods usually mean the comprehensive metabolic panel, which adds liver and protein tests to make fourteen. And when people talk about "metabolic health", they mean something neither of those covers well: how the body handles glucose and fat over months. This page sorts out the three.

The basic metabolic panel (BMP)

MedlinePlus lists the BMP as eight of the fourteen CMP tests: glucose, calcium, sodium, potassium, bicarbonate (often reported as CO2), chloride, blood urea nitrogen and creatinine. It is designed for speed and for acute questions. Is this person dehydrated? Is potassium safe? Are the kidneys clearing waste? It is what gets drawn in an emergency department and before many procedures.

The comprehensive metabolic panel (CMP)

The CMP adds six tests to the BMP: albumin, total protein, alkaline phosphatase, ALT, AST and bilirubin. Those add a liver and nutrition dimension. Most routine annual bloodwork in the US includes a CMP, and most labs report an eGFR calculated from its creatinine. The CMP guide goes through all fourteen.

What neither panel tells you

Both panels contain one glucose measurement, and it is a snapshot. If you ate before the draw it is not even a fasting value. Neither panel includes:

• HbA1c, which reflects average glucose over roughly two to three months and is a diagnostic test for diabetes in the ADA Standards (6.5 percent or more is diabetes; 5.7 to 6.4 percent is prediabetes).
• Fasting insulin, which can rise years before glucose does, because the pancreas compensates for insulin resistance by making more. It has no guideline cut-off and assays differ between labs.
• A lipid panel: total, LDL and HDL cholesterol, and triglycerides. Triglycerides in particular move with insulin resistance, alcohol and weight. See the lipid panel guide.
• Uric acid, which tracks with insulin resistance and kidney handling as well as with gout.
• Vitamin D (25-OH), which is not a metabolic test in the lab sense but is often ordered alongside.

The cardiometabolic version

When people say "metabolic health" they usually mean five things clinically: waist, blood pressure, fasting glucose or HbA1c, triglycerides and HDL. Three of those are blood tests. The ADA Standards recommend screening for diabetes in all adults from age 35, and at any age with overweight or obesity plus at least one risk factor, repeating at least every three years when normal. The tests it accepts are HbA1c, fasting plasma glucose, or a two-hour glucose after a 75 g oral glucose tolerance test. Fasting, for that purpose, means no caloric intake for at least eight hours.

How the markers talk to each other

Read singly, each metabolic marker is a weak signal. Read together they make a pattern. Rising fasting insulin with steady glucose suggests the pancreas is working harder to hold the line. High triglycerides with low HDL is the lipid fingerprint of insulin resistance. A raised ALT with high triglycerides and a large waist is the common shape of fatty liver. HbA1c that looks too good for the fasting glucose sometimes means something is shortening red cell life, which is why the ADA notes that HbA1c may not be a suitable diagnostic test in people with anaemia, some haemoglobin variants or other conditions that change red cell turnover.

Where each marker can mislead

• Creatinine reflects muscle mass as well as kidneys. Heavy training, high muscle mass and creatine supplements raise it; large weight loss can lower it. KDIGO 2024 suggests cystatin C when that matters.
• ALT and AST rise for days after hard resistance exercise, because muscle contains them too.
• Glucose and triglycerides depend on the last meal. A non-fasting value is not wrong, it is answering a different question.
• BUN moves with hydration and protein intake, which is why it is read alongside creatinine rather than alone.

Units, and the numbers that look wrong

Most US labs report metabolic markers in conventional units and most of the rest of the world uses SI units. Glucose in mg/dL divided by about 18 gives mmol/L, so 90 mg/dL is about 5.0 mmol/L. The ADA gives HbA1c both ways: 6.5 percent is 48 mmol/mol, and the prediabetes band of 5.7 to 6.4 percent is 39 to 47 mmol/mol. Creatinine in mg/dL multiplied by 88.4 gives micromoles per litre. A result that looks alarming next to a figure you read online is often a unit mismatch, so read the unit printed beside the number before anything else.

Which to order

That is a clinical decision, and the what blood tests to get page lays out the guideline basis by situation. As a rough guide, a CMP covers organ function; HbA1c and a lipid panel cover the slow metabolic story; fasting insulin and uric acid add detail that some clinicians find useful and others do not. On a GLP-1, the GLP-1 blood work page shows which of these moved in the trials.

In the app

Peptide AI's metabolic panel takes the overlap that matters for tracking over time: fasting glucose, fasting insulin, HbA1c, the four lipid values, ALT, AST, eGFR, creatinine, BUN, uric acid and vitamin D, scored together and plotted against your dose timeline. The panels page lists each one, and bloodwork tracking covers upload.