Vitamin C
A water-soluble antioxidant essential for collagen synthesis, immune function, iron absorption and neurotransmitter production.
Central to connective tissue repair — genuinely relevant to anyone training hard, recovering from injury, or working on tendon health. Also markedly depleted by smoking and chronic stress.
Optimal ranges, root causes, and the complete correction protocol — nutrition, supplements, lifestyle, hormones and peptides — plus 100+ other markers.
Unlock everything — $10/mo →📚 Institute of Medicine DRI for vitamin C. Carr AC, Maggini S, Nutrients 2017 — vitamin C and immune function.
🩸 Test your Vitamin C
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 Vitamin C is usually tested alongside
On its own, one marker is a data point. These panels include Vitamin C 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.
includes this + 10 more markers — Restrictive diet, plant-based, post-bariatric, on a GLP-1, heavy training load, or you just want to stop guessing which supplements you actually need.
Would you feel it? Symptoms Vitamin C 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.
Why your Vitamin C 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.
Ascorbate oxidises quickly in the tube. Samples need protection from light, prompt processing and often acid stabilisation, or the result reads falsely low.
A low vitamin C from a lab that isn't set up for it is more likely a handling problem than scurvy.
Serum ascorbate reflects the last day or two, not tissue stores.
Draw fasted, before any supplement.
Both genuinely lower vitamin C — smokers have measurably higher requirements.
A real deficiency, not an artefact. Correct it.
What Vitamin C 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.
That is a malabsorption pattern, not a diet pattern. Coeliac disease, atrophic gastritis, H. pylori, pancreatic insufficiency and inflammatory bowel disease all present this way, and correcting the individual nutrients without finding the cause is a treadmill.
Investigate why absorption is failing rather than supplementing indefinitely. Coeliac serology must be done before removing gluten. Any neurological symptom with low B12 or copper needs urgent attention.
What to test next
Markers rarely answer alone. These are the ones that put Vitamin C in context — each with its own full breakdown.
Frequently asked questions
0.4–2.0 mg/dL Ranges vary by laboratory and assay — always compare to the range printed on your own report.
Optimal ranges, root causes and the full correction protocol are available inside Coach Cam's Peptide Academy.
See the full breakdown inside the Academy.
See the full breakdown inside the Academy.
You can order Vitamin C directly through Marek Diagnostics without a doctor's visit — drawn at any Quest Diagnostics location in the US. Code CAMERON applies 10% off automatically.