Zinc (serum/plasma zinc)

Pick Ordered or Not ordered to see the note.

Indicated when

• —Suspected zinc deficiency in a defined risk group: malabsorption syndromes, significant chronic diarrhea, total parenteral nutrition, or after bariatric or gastric bypass surgery [1]
• —Monitoring in a patient on chronic high-dose zinc supplementation, particularly alongside copper, since excess zinc intake can itself cause copper deficiency [2]
• —Growth faltering in a child where dietary zinc intake or absorption is a concern, interpreted together with growth response to supplementation rather than the level alone [1]

Not indicated when

• —Routine or 'wellness panel' screening for fatigue or general immune support with no malabsorption, GI surgery, or relevant dietary risk factor [3]
• —Interpreting a single plasma zinc result during acute illness or inflammation without accounting for that effect [1]

Why not

Plasma zinc concentration is influenced by recent meal consumption, the time of day, inflammation, and certain drugs and hormones, so a single value can be misleading if these factors are not accounted for, and the BOND expert panel found several other proposed biomarkers, including hair, urinary, nail, and blood cell zinc, do not have enough evidence to be recommended for assessing zinc status [1].

Better first step

For fatigue or a general concern with no defined risk factor, look for a more likely cause before testing zinc. When a real risk factor is present, malabsorption, bariatric surgery, TPN, or high-dose zinc supplementation, plasma zinc is a reasonable first test interpreted alongside the clinical picture [1].

Typical ND rationale

An ND may order zinc for a patient with frequent infections, slow wound healing, hair loss, or as part of a general nutrient panel, reasoning that zinc is essential for immune function and wound healing and that a mild deficiency can otherwise be missed.

Ontario coverage & CONO orderability

OHIP status

insured

L266 Zinc is listed in the 2026 Schedule of Benefits for Laboratory Services with no restricting condition, so it is insured when a physician orders it after clinically assessing the patient ([4]; Reg. 552 s.22). ND-ordered testing is patient-paid regardless [7].

CONO orderable

Yes — CONO list #133

CONO list item 133, blood: 'Zinc.'

Linked conditions

• tired ↗

Counselling script

“If you have a gut condition affecting absorption, have had weight-loss surgery, or take high-dose zinc supplements regularly, checking zinc makes sense. Without one of those, I wouldn't add it to routine bloodwork, since a single zinc level can be affected by things like recent meals or inflammation and often doesn't give a clear answer on its own.”

Revisit if

• —Malabsorption, chronic diarrhea, or a new diagnosis affecting nutrient absorption develops
• —Bariatric or gastric surgery, or starting total parenteral nutrition
• —Starting or continuing high-dose zinc supplementation

References

1. [1]Biomarkers of Nutrition for Development (BOND) Project (2016). Biomarkers of Nutrition for Development (BOND)-Zinc Review. linkPlasma zinc concentration is influenced by recent meal consumption, time of day, inflammation, and certain drugs and hormones; other proposed zinc biomarkers lack sufficient evidence to be recommended
2. [2]Annals of Hematology (2018). Copper deficiency anemia: review article. linkExcess zinc intake can cause copper deficiency, so zinc and copper are monitored together in that setting
3. [3]College of Family Physicians of Canada / Choosing Wisely Canada (2026). Family Medicine: Fifteen Tests and Treatments to Question. linkDon't do annual screening blood tests unless directly indicated by the patient's risk profile
4. [4]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026) - L266 Zinc. linkL266 Zinc is listed in the 2026 OHIP Schedule with no restricting condition
5. [5]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026). linkCommunity lab tests are insured only when ordered under the Schedule by an authorized prescriber
6. [6]Government of Ontario (e-Laws) (2026). Health Insurance Act, R.R.O. 1990, Reg. 552: General, s. 22 (insured laboratory services). linkA lab test is insured only when ordered by a physician, midwife, or NP who has clinically assessed the patient
7. [7]Ontario Ministry of Health (2026). Ontario Health Insurance Plan: Schedule of Benefits for Laboratory Services (effective April 1, 2026). linkTests ordered by anyone other than an authorized provider, including NDs, are not insured services