Plasma zinc is a direct blood measure of the zinc circulating in plasma, about 0.1% of the body's total and mostly bound to albumin. Practitioners use it for clients with low-meat diets, malabsorption, poor wound healing, recurrent infections or long-term zinc use. Inflammation, low albumin, pregnancy, the pill and afternoon or post-meal samples all lower it, so read it with CRP and albumin.
| Test type | Measured in a blood sample |
|---|---|
| Measurements required | Plasma zinc only |
| Sample and collection | Blood draw at a collection centre |
| Preparation | Book a morning collection and fast overnight beforehand (water is fine), as plasma zinc falls after meals and through the day. |
| Turnaround | About 5 to 10 business days |
| Available through | Vitamins & Trace Elements. |
| Pricing | Price on sign-up |
| Results | Returned in the Vively practitioner platform, beside your client's other markers |
What are the Plasma zinc reference and optimal ranges?
| Typical lab reference | Vively optimal | |
|---|---|---|
| Adults | 10 to 20 µmol/L | 15 to 20 µmol/L |
Labs differ, so read the result against the range printed on the client's report (RCPA guidance). The optimal range is a target for tracking, not a diagnostic cut-off.
Check a client's Plasma zinc result
Enter the value from your client's lab report to see where it sits against the typical lab range and the Vively optimal range.
A guide only, not a diagnosis. One result is a starting point: read it with symptoms, history and a repeat test. Labs differ, so check the result against the range on your client's report. Nothing you enter is stored or sent.
How do you arrange Plasma zinc testing through Vively?
- Get verified. Practitioners with a recognised qualification or membership (ATMS, NHAA, ANTA, Dietitians Australia, NSA, CMA or Ahpra registration) can request free practitioner access.
- Choose a panel. Log in to the practitioner platform and pick a panel that includes Plasma zinc, or build your own. Add-on pricing shows when you sign up.
- Client collects. Your client collects at a partner collection centre, with their request on their phone or printed.
- Review results. Results come back to you in the practitioner platform, beside your client's other markers, ready for the follow-up consult.
Why does the optimal range sit there?
Our 15 to 20 µmol/L band sits above the lower third of the lab range, where marginal status and sampling effects overlap.
Homeostasis holds plasma zinc steady until intake has been low for some time, and it drops with inflammation, low albumin, meals and afternoon sampling (IZiNCG, 2012).
Sustained high zinc intake blocks copper absorption, and zinc-induced copper deficiency can cause anaemia, low neutrophils and neuropathy.
Neither bound comes from outcome trials. A client within the band is unlikely to be short of zinc, even allowing for timing.
What should Plasma zinc be read with?
- LowLow zinc with raised hs-CRP
Can reflect the acute phase response moving zinc into the liver; repeat once CRP settles before calling it deficiency.
- LowLow zinc with low albumin
Less binding protein lowers total plasma zinc; consider protein intake, liver or gut causes.
- HighHigh zinc with low neutrophils or low haemoglobin
Possible zinc-induced copper deficiency in a client taking zinc; needs GP review and a copper level.
- LowLow zinc with low ferritin and low B12
Raises the question of malabsorption (coeliac disease, IBD) or a restrictive diet.
- LowLow zinc with high HbA1c
Often seen with poorly controlled diabetes, where urinary zinc losses rise.
What can affect a Plasma zinc result?
- Time of day and meals: afternoon and post-meal samples run lower than morning fasting ones
- Inflammation, infection and recent surgery lower plasma zinc
- Low albumin, pregnancy and the oral contraceptive pill lower results
- Haemolysis raises results, as red cells contain far more zinc than plasma
- Contamination from standard tubes; labs need trace-element tubes for an accurate result
- Zinc supplements or zinc lozenges in the past day raise results
When should you refer the client to their GP?
- Below the lab range with diarrhoea, skin lesions around the mouth or extremities, or poor wound healing
- Above the lab range in a client taking zinc, especially with fatigue, low neutrophils, anaemia or numbness, which can point to copper deficiency
- Persistently low despite adequate intake, which can point to malabsorption, kidney or liver disease
- Clients with IBD, coeliac disease, bariatric surgery or a high-output stoma
How should a client prepare for a Plasma zinc test?
Copy or print this to send to your client.
Preparing for your Plasma zinc test
- Book a morning collection and fast overnight beforehand (water is fine), as plasma zinc falls after meals and through the day.
- Tell your practitioner if you've taken zinc in the 24 hours before your test, including in a multivitamin.
- Take your pathology request to any of 4,000+ collection centres. Bring it printed or on your phone.
- Keep taking prescribed medicines as usual unless your doctor tells you otherwise.
- Results usually take about 5 to 10 business days and come to your practitioner. Book your results appointment for after that.
How do practitioners use Plasma zinc with clients?
Ask for a morning fasting collection and check hs-CRP on the same draw; without both, a low-normal zinc cannot be separated from timing or inflammation. When a client already takes zinc, check how long they have taken it and whether the product also contains copper.
Plasma zinc FAQs
Can a naturopath, nutritionist or dietitian order plasma zinc through Vively?
Yes. Add it to any client panel on the Vively practitioner platform. It sits in Vitamins & Trace Elements. Add-on pricing shows when you sign up. No account yet? Request free access.
Does a normal plasma zinc rule out zinc deficiency?
No. Plasma zinc stays in range until deficiency is fairly advanced, so a normal result in a client with a low-zinc diet and suggestive signs does not settle the question. Read it with diet history, CRP and albumin, and trend it over time. Hair zinc is not a validated alternative for individual clients.
Why does collection timing matter for zinc?
Plasma zinc falls after meals and over the course of the day, enough to move a borderline result across the lower limit. IZiNCG sets separate cut-offs for morning fasting, morning non-fasting and afternoon samples for that reason. Book an early morning fasting collection and keep the timing the same for repeat tests.
Why read plasma zinc alongside CRP and albumin?
Both shift the result without any change in zinc intake. Inflammation moves zinc into the liver, and low albumin means less binding protein, so total plasma zinc falls. Check hs-CRP on the same draw. If it is raised, repeat once it settles before calling a low zinc deficiency, and consider protein intake, liver or gut causes when albumin is low.
Can a high plasma zinc be a problem?
Yes, in a client taking zinc. Sustained high intake blocks copper absorption, and zinc-induced copper deficiency can cause anaemia, low neutrophils and neuropathy. Check how long they have taken it and whether the product contains copper, and note that haemolysis or zinc taken in the previous day can also raise the result. A high result with those blood count changes needs GP review and a copper level.
References
- Royal College of Pathologists of Australasia. RCPA Manual: Zinc.
- International Zinc Nutrition Consultative Group (IZiNCG). Assessing population zinc status with serum zinc concentration. Technical Brief No. 2. 2012. Source
- King JC, Brown KH, Gibson RS, et al. Biomarkers of Nutrition for Development (BOND): zinc review. Journal of Nutrition. 2016. Source