Serum zinc optimal range and reference range

Compiled by Alina Radu, founder of Sera, from the published sources below · Last reviewed November 9, 2026

Sera's bands for Serum zinc:

Optimal 90 – 120 μg/dL (14 – 18 μmol/L); sufficient 70 – 150 μg/dL (11 – 23 μmol/L); out of range below 70 or above 150 μg/dL.

Evidence grade: Published reference interval. A band that primarily reflects a published adult laboratory or population reference interval. It is not necessarily applicable to every assay or laboratory.

At Sera's last range review a change to this band was proposed and held, because the evidence for it was thin, so the band is unchanged. The note below says where it matches published intervals and where it does not.

All units

Unit	Optimal	Sufficient	Out of range
μg/dL	90 – 120	70 – 150	below 70 or above 150
μmol/L	14 – 18	11 – 23	below 11 or above 23
mg/L	0.9 – 1.2	0.7 – 1.5	below 0.7 or above 1.5

What the evidence says

The acceptable band of 70 to 150 μg/dL (11 to 23 μmol/L) is close to one UK trace-element laboratory's interval of 11 to 24 μmol/L. Other laboratories run lower: ARUP 60 to 120 μg/dL and Labcorp 44 to 115. The optimal upper edge of 120 equals ARUP's upper limit; the optimal lower edge of 90 has no source. Serum zinc falls after meals and with inflammation.

Assay: Results differ meaningfully between platforms and methods. Compare against the interval printed by the issuing laboratory before acting on a borderline value.

Sources

Zinc (Plasma/Serum) — Black Country Pathology Services (Trace Elements Laboratory, Sandwell; NHS), 2026 · Laboratory / reference-interval sourceReference range for all ages 11 to 24 µmol/L; deficiency may be indicated below 7.0; above 24 suggests supplement use or contamination. Matches Sera's acceptable band of 11 to 23 µmol/L (70 to 150 µg/dL).
Zinc, Serum or Plasma — ARUP Laboratories, 2026 · Laboratory / reference-interval sourceARUP's interval is 60 to 120 µg/dL. The upper limit equals Sera's optimal upper edge; the lower limit is below Sera's 70. Notes that zinc falls with infection, inflammation, oral contraceptives and pregnancy.
Zinc, Plasma or Serum — Labcorp, 2026 · Laboratory / reference-interval sourceLabcorp's interval from 11 months of age is 44 to 115 µg/dL for both sexes, well below Sera's lower edge of 70. Zinc should be read with serum albumin.
Zinc, serum — Newcastle Hospitals NHS Foundation Trust — Newcastle Laboratories, 2026 · Laboratory / reference-interval sourceSex- and age-specific intervals by ICP-MS: 19 to 64 years, women 9.6 to 20.5 and men 10.1 to 20.2 µmol/L. Advises measuring two weeks after an acute phase response has resolved.
Serum Zinc Concentrations in the US Population Are Related to Sex, Age, and Time of Blood Draw but Not Dietary or Supplemental Zinc — Hennigar SR, Lieberman HR, Fulgoni VL, McClung JP — The Journal of Nutrition, 2018 · Peer-reviewed publicationUS population means are 84.9 µg/dL in men and 80.6 in women, both below Sera's optimal lower edge of 90. Afternoon and evening draws read about 10 to 15 µg/dL lower, and serum zinc did not track zinc intake.

What Zinc (Serum) measures

Serum zinc, the circulating fraction — distinct from the red cell compartment, which reflects a longer window.

Falls during any acute-phase response independently of status, so a low serum zinc alongside a raised CRP usually reflects inflammation rather than deficiency. That is the main reason to measure the red cell compartment as well.

Related vitamins & minerals markers

See Serum zinc in the full list of biomarker ranges

This page is a reference for practitioners, not medical advice. Sera's bands are practitioner targets for structured review, not diagnostic thresholds, and Sera does not diagnose or recommend treatment. Read a result alongside the interval printed by the issuing laboratory and the client's history and symptoms. Range set: Sera Production, version 1.0, last reviewed November 9, 2026.