Carnitine, Total and Free

Also known as: L-carnitine

A compound that shuttles long-chain fatty acids into mitochondria to be burned for energy.

Central to fat oxidation and mitochondrial energy production. Deficiency is uncommon but meaningful in vegetarians, dialysis patients, and certain metabolic conditions — and it's relevant to the TMAO conversation.

🔒 The full Carnitine, Total and Free protocol is inside the Academy

Optimal ranges, root causes, and the complete correction protocol — nutrition, supplements, lifestyle, hormones and peptides — plus 100+ other markers.

Unlock everything — $10/mo →

📚 Koeth RA et al., Nat Med 2013 — carnitine, gut microbiota and TMAO.

🩸 Test your Carnitine, Total and Free

Order directly through Marek Diagnostics — no doctor's visit needed, drawn at any Quest location in the US. Code CAMERON applies 10% off automatically.

Order this test — 10% off → Browse all 102 markers →

What Carnitine, Total and Free is usually tested alongside

On its own, one marker is a data point. These panels include Carnitine, Total and Free plus the markers that make it interpretable — each names every test, why it is on the list, and loads the whole set into your cart in one click at 10% off.

🍭 Metabolic Health & Prediabetes $81.45
includes this + 7 more markers — Weight that won't shift, energy crashes after meals, expanding waistline, family history of diabetes, or a fasting glucose that's crept into the 90s.
🫀 Real Cardiovascular Risk $187.60
includes this + 8 more markers — Anyone over 30, anyone with a family history of early heart disease, or anyone who's been told their cholesterol is 'fine' and wants to know what that actually means.
🌸 PCOS Workup $225.90
includes this + 9 more markers · built for women — Irregular or absent periods, acne, unwanted hair growth, scalp thinning, difficulty losing weight, or you've been told 'probably PCOS' without a workup.

What moves your Carnitine, Total and Free

2 compounds and 2 supplements in the Vault have a documented effect on this marker, or are a reason to have measured it first:

L-Carnitine — The actual level — worth knowing before and after
SS-31 — Mitochondrial fuel handling
L-Carnitine L-Tartrate — The actual level — worth knowing before and after
Urolithin A — Mitochondrial function — the mechanism actually being claimed

Browse all 237 compounds & 350 supplements →

Would you feel it? Symptoms Carnitine, Total and Free helps explain

People rarely search for a marker — they search for how they feel. These are the complaints where this marker is worth checking, and whether it is a first-line test or a follow-up once the obvious causes are ruled out.

💊 I take a lot of supplements — is any of it actually working?then

Why your Carnitine, Total and Free might be wrong

Most abnormal results are interference, not disease. These are the things that measurably move this specific marker — check them before you change anything. Each one says whether the number is wrong and should be repeated, badly timed and should be redrawn, or real with a cause worth explaining.

💊 Valproate, pivalate antibioticsA real change — account for the cause

Valproate and pivalate-containing antibiotics both deplete carnitine substantially over months of use, by conjugating it and forcing renal loss.

Note any long-term use — it is the likeliest explanation for a low result.

🏃 Kidney impairment and dialysisA real change — retest once it passes

Alters carnitine handling markedly in both directions depending on stage.

Interpret alongside kidney function.

🕐 Fasting stateThe value is real but reflects a moment — retime it

Rises after eating, so a non-fasted draw measures your breakfast rather than your baseline.

Draw fasted, 10–12 hours, water only.

What Carnitine, Total and Free means in combination

A single marker tells you a little. Combinations tell you the story — these are the named patterns this marker takes part in, and what each one points at.

The plant-based gap
B12 low · Ferritin low · Carnitine low · Vitamin D low · Zinc low

A well-run plant-based diet is fine, but four nutrients are genuinely harder to get and this combination shows a diet that has not been supplemented deliberately.

B12 is non-negotiable and non-optional — deficiency causes irreversible neurological damage. Add iron with vitamin C away from tea and coffee, plus vitamin D, zinc and an algal omega-3. Retest in 3 months.

What to test next

Markers rarely answer alone. These are the ones that put Carnitine, Total and Free in context — each with its own full breakdown.

Frequently asked questions

What is a normal Carnitine, Total and Free level?

Total 30–89 µmol/L, free 22–66 µmol/L Ranges vary by laboratory and assay — always compare to the range printed on your own report.

What is the optimal Carnitine, Total and Free level?

Optimal ranges, root causes and the full correction protocol are available inside Coach Cam's Peptide Academy.

What causes high Carnitine, Total and Free?

See the full breakdown inside the Academy.

What causes low Carnitine, Total and Free?

See the full breakdown inside the Academy.

How do I test Carnitine, Total and Free?

You can order Carnitine, Total and Free directly through Marek Diagnostics without a doctor's visit — drawn at any Quest Diagnostics location in the US. Code CAMERON applies 10% off automatically.

Important: This page is education only. The ranges shown are published reference and functional ranges from the cited literature — not a diagnosis and not medical advice. Lab ranges vary by assay and laboratory; always compare against the range printed on your own report and discuss your results with a qualified healthcare provider.