Vitamin C
A blood sample measures serum vitamin C directly. The body cannot synthesise it and stores almost none, relying entirely on daily intake — so blood levels reflect not how much you have taken, but the real balance between intake and consumption.
Worth testing if:
- You supplement vitamin C but aren't sure the dose is enough
- You live with sustained stress, late nights or an irregular schedule
- You smoke, or are regularly exposed to second-hand smoke
- You eat out often and your fruit and vegetable intake is low
- Wounds heal slowly, gums bleed easily, or skin problems keep recurring
- Your immunity fluctuates and you catch colds easily
- You are supplementing iron and want to confirm the cofactor conditions are in place
What this test is for
A blood sample measures serum vitamin C directly. Vitamin C is a key antioxidant nutrient supporting collagen synthesis and immune function while countering the free-radical damage produced by stress.
It differs from other nutrients in one respect: the body cannot synthesise it and stores almost none, relying entirely on daily dietary intake. That means blood levels reflect not the total you have taken, but the recent balance between intake and consumption — stress, late nights, smoking, infection and post-operative recovery all accelerate consumption, so a dose that was once adequate can suddenly fall short.
Its other, commonly overlooked role is iron absorption. Vitamin C reduces ferric iron to the better-absorbed ferrous form, a key condition for whether plant-based iron can be used by the body. When iron supplementation is not working, the gap is sometimes not iron itself, but vitamin C.
Test items
1 biomarkers
Vitamin C (Ascorbic Acid)
Four steps to start your test
Order online, book a location
Choose your test and pick a blood-draw time and location that suits you as you order.
A 10-minute blood draw
When the time comes you just show up. A professional takes your sample — we handle the rest.
Accredited laboratory analysis
Samples are processed by accredited testing institutions and interpreted to standard protocols.
Digital report
Once complete, your report is uploaded to your personal account with values and reference ranges clearly marked.
Pair it with Body Decode for the full picture
This test isn't part of the core package. Build a whole-body baseline with Body Decode, then add this test on top for fuller health context
| Body Decode + this add-on | This test on its own | |
|---|---|---|
| Number of biomarkers | 68 + this test's 1 | This test's 1 only |
| Biomarkers on this page | ||
| Cross-system interpretation | ||
| Full-system integrated report | ||
| Advisor report walkthrough | ||
| Personalized action plan | ||
| 120-day check-ins |
Frequently asked questions
I take vitamin C daily — do I still need to test?
Vitamin C is barely stored; whatever is surplus is excreted, so blood levels depend on the moment-to-moment balance between intake and consumption. Stress, late nights, smoking, infection and post-operative recovery all sharply raise the rate of consumption, and a dose that was once adequate may no longer be.
Serum levels tell you whether your dose matches your current consumption.
Isn't eating more fruit enough?
Vitamin C degrades with heat, light and storage time, and losses continue from harvest to plate. The amount you actually absorb from the same portion can differ considerably from the nutrition table — and since consumption rates vary between people, a food diary cannot reliably estimate it.
Measure blood levels directly, instead of estimating.
Excess is excreted, so overdosing isn't a concern?
Vitamin C is indeed water-soluble and excreted in excess, but sustained high doses still carry a cost — gastrointestinal discomfort in some people, and a possible increase in oxalate stone risk. "Non-toxic" is not the same as "the more the better".
Knowing your level is what lets you decide to raise or lower the dose.
What does vitamin C have to do with iron?
Vitamin C reduces dietary ferric iron to the better-absorbed ferrous form, which matters most for plant-based iron. When iron supplementation has run for a while without moving the numbers, the problem is sometimes not the iron itself but this missing cofactor.
Especially worth reading together for vegetarians and anyone supplementing iron.
How is this different from the Essential Nutrients Panel?
This test covers vitamin C only — suited to anyone who already knows which marker they want to track, or who wants a before-and-after comparison around a dose change. The six-marker Essential Nutrients Panel adds vitamin D3, B12, folate, ferritin and coenzyme Q10, revealing gaps across haematopoiesis, methylation, immunity and energy metabolism at once.
Single-marker tracking? This one. The full picture? The six-marker panel.