Almost every figure on a hair mineral analysis carries a footnote about which laboratory produced it. Zinc to copper is the exception. Trace Elements puts the ideal at 8; Analytical Research Labs puts it at 8. Two lineages that disagree about calcium, about sodium, and about how to read half the chart agree here — a fair signal the ratio carries something the readings themselves do not.
Zinc and copper are direct antagonists. Zinc keeps copper in check, and excess copper produces a relative zinc deficiency — not by removing zinc from the diet, but by raising the metabolic demand for it faster than intake can meet. Copper is a sedative, anabolic mineral that increases parasympathetic activity; zinc is the steadying, anti-stress element on the other side of the seesaw. The consequence is arithmetic. Hold copper at the ideal 2.5 mg% and move zinc alone:
| Zinc | Copper | Zn/Cu | Where that lands |
|---|---|---|---|
| 30 mg% | 2.5 mg% | 12 | Top of both laboratories' acceptable windows |
| 20 mg% | 2.5 mg% | 8 | The ideal, on both reference sets |
| 12 mg% | 2.5 mg% | 4.8 | Below the ARL window entirely |
The copper reading never moved; a practitioner reading only that column would report the same thing three times. Watts gives the mirror-image case in his 1988 zinc paper: a zinc of 12 mg% — frankly low — against a copper of 0.5 mg% produces 24 to 1, three times ideal. That chart is zinc-deficient in absolute terms and zinc-dominant in relative terms at once, and the ratio is the only place it shows.
The governing thesis, in one line from Trace Elements: deficiencies and excesses matter, but the relationship between the nutrients matters more. Subclinical deficiencies are estimated to outnumber frank ones ten to one, and a relative deficiency is invisible to any test reporting one element at a time.
| Marker | Ideal | Acceptable range |
|---|---|---|
| Zinc | 20 mg% | Normal band 15–22 mg% |
| Copper | 2.5 mg% | Both tails are read as dysregulation |
| Zn/Cu | 8 — both laboratories | Trace Elements 4–12 · ARL 6–12 |
| Zn/Cd (toxic pairing) | — | Minimum 500 : 1 |
The two windows differ on the low side. ARL draws its floor at 6, Trace Elements at 4, so a chart reading 5.2 is inside one acceptable range and outside the other — a reference-set difference rather than a contradiction, and the reason a ratio should never be quoted without naming the laboratory. Both sets assume unwashed hair.
The ARL trend table divides the low side into two bands, and its language is copper-forward rather than zinc-forward.
The point ARL states flatly and repeats: a low Zn/Cu is read as a copper trend even when the copper level is unremarkable. Copper elevates sodium and depresses potassium, so a chart can carry copper's fingerprints in three or four places while the copper column looks ordinary — potassium under 3–4 mg%, calcium over about 80 mg%, Ca/K above 30 to 1, Na/K under 2 to 1. A cluster, not a single number.
This is the half nobody writes about. Trace Elements closes its 1989 copper paper with the sentence that ought to end the argument: just as much consideration should be given to the possibility of copper deficiency as to copper toxicity. Copper runs cytochrome c oxidase, ceruloplasmin, tyrosinase and lysyl oxidase, the enzyme governing elastin quality and collagen cross-linking. A chart drifting high is one to read carefully.
Two things inflate the high side artificially. Cadmium elevates the zinc reading, because it displaces zinc in more than seventy enzyme systems and the displaced zinc reports into hair. And a hair copper below about 1.0–1.1 mg% is read as a decreased ability to release copper from storage, not a simple shortage. Either one pushes Zn/Cu upward for reasons that have nothing to do with an improving picture.
Copper can only be used when bound to a transport protein, and the main one is ceruloplasmin — synthesised in the liver under adrenal stimulation. When adrenal activity is low the liver under-produces it, and copper that has nowhere to bind can be neither used nor readily excreted. It accumulates in tissue, principally liver and brain, while the copper-dependent enzymes go unserved: excess total-body copper coexisting with functional copper shortage.
That is why both tails of the copper column point at the same thing — ARL defines bio-unavailable copper as a reading above 3.0 or below 1.0 mg%. The normal exit route is bile, so anything slowing biliary flow accumulates copper quietly over years at ordinary intake. Copper sequestered in organs the test does not sample may not appear on a first chart at all; it commonly surfaces on a second or third, which is why a rising copper figure on a retest is generally read as copper on its way out.
Watts organises interpretation gland by gland rather than around a single metabolic rate. Zn/Cu appears in two of those columns, on opposite sides.
| Column | Zn/Cu reading | Read alongside |
|---|---|---|
| Increased ovarian (estrogen) activity | Zn/Cu below 8 | Ca/Mg above 8, Ca/K above 4, Ca/P above 2.6 |
| Decreased thyroid activity | Zn/Cu above 8 | Ca/K above 4, Ca/P above 2.6, Na/Mg below 4, a low Fe/Cu |
Two cautions belong with that table. These are readings of gland activity trends, not conditions — a chart does not say a thyroid is underactive, it says a group of ratios is sitting where decreased thyroid activity tends to sit, over the last two to three months of growth. And no row is read alone; the estrogen column wants four ratios pointing the same way. The mechanism is documented in both lineages: estrogen retains copper and excretes zinc, so anything raising estrogen exposure moves both halves at once.
Zinc is also the nutrient cadmium is measured against, at a minimum Zn/Cd of 500 to 1. Every toxic ratio works this way: the metal is judged against the nutrient that antagonises it, so a ratio can fail while the metal sits inside its own limit — cadmium's being under 0.04 mg%. Cadmium raises sodium through an aldosterone-like effect, lowers copper, and substitutes for zinc across many enzyme systems, which is why a failing Zn/Cd and an inflated Zn/Cu so often arrive together. The rest of the minimums, Ca/Pb at 84 to 1 and Zn/Hg at 200 to 1 among them, are in the article on reading the toxic ratio block.
Not by supplementing the number. Eck's account of taking 60 mg of zinc for a suspected deficiency, and getting anxiety and fearfulness he had not had before, produced the line the literature keeps returning to: taking a mineral does not necessarily raise that mineral. Dosing on a report is written as a schedule such as 1-1-0 or 2-2-2 across morning, noon and evening, set by the practitioner from the chart rather than from a bottle label. The ranges we hand-select from — the Endo-Met line and the Trace Elements line — are chosen the same way, and the choice often turns on which side of 8 this ratio sits.
The rest is sampling discipline and time: scalp hair, no more than 1.5 inches from the scalp, roughly 250 mg, unwashed. Each report averages two to three months of growth, which is why a retest at three to five months tells you more than any adjustment in between. And compare retests within the same laboratory — the two reference sets are not interchangeable.
None of the above is a recommendation for any individual — which pattern you carry is what the test is for. Start with a tissue mineral analysis kit and follow the sampling instructions exactly. The 1.5-inch rule alone is the difference between a current reading and years of accumulated exposure.
I came to hair analysis in 2010, under ARNP Julie Walker in Kennewick, Washington. I worked directly with Analytical Research Labs, testing family and friends, and I listened to every cassette Dr. Paul Eck recorded and read every ARL newsletter that came through. I signed up with Dr. Larry Wilson in August 2011 and have practised independently since autumn 2017.
My background before any of that was nuclear quality engineering, which is probably why this is the ratio I trust most on a first chart. In that work you learn early that one instrument reading is nearly worthless without a second measurement to check it against. Zinc to copper is that second channel — the number I read before I have any opinion about the copper column.
The common misreading is to see a modest copper figure on a report and conclude the subject does not apply — on a low Zn/Cu the copper column is not where the pattern shows itself.
Curated by Practitioner Eileen Durfee, NBS (Nutritional Balancing Science), NASM-CPT — wellness educator, inventor with 10 U.S. and 6 international patents, and former nuclear quality engineer
This article is the numbers. The companion piece on EileenDurfee.com is the experience — what copper does to sleep, to mood, to chocolate cravings, and why it has been called the mineral with a double life.
Both — they answer different questions. The copper column reports a quantity; the ratio reports a relationship, and in this literature the relationship outranks the reading. A low Zn/Cu is treated as meaningful even when copper sits in range, partly because copper also elevates sodium and depresses potassium, so its influence shows up in several places on a chart before it shows in its own column.
Not automatically. Above 8 is read as a copper-deficiency or copper-unavailability trend, and two artefacts push it there for the wrong reasons — cadmium elevating the zinc reading, and a very low copper figure reflecting an inability to release copper from storage rather than a shortage of it.
Please do not decide that from an article. Zinc and copper are antagonists, so moving one moves the other, and prolonged high zinc intake is documented to produce copper, iron, chromium and manganese deficiencies. The dose on a report is set by the practitioner reading your chart, and written as a daily schedule rather than a label serving.
This article is for educational purposes only. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. Hair tissue mineral analysis is a screening test for nutritional and toxic element status and is not a diagnostic test. Nuco Enterprise Solutions LLC.
