Two practitioners can read the same hair mineral analysis and put the same person on two different programmes. When that happens, the calcium-to-phosphorus ratio is usually the reason. It is the one number where the two major interpretive systems agree completely on what it means and disagree on what to do about it.
Ca/P is tissue calcium in milligrams percent divided by tissue phosphorus in milligrams percent. The interpretation sits entirely in where the quotient lands.
| Value | Figure, with its lineage |
|---|---|
| Ideal Ca/P | 2.5 to 2.6 — 2.5 in the Analytical Research Labs set, 2.6 in the Trace Elements governing set (Nov–Dec 2010). |
| Trace Elements acceptable range | 1.8 – 3.6 in the 2010 set. The 1993 floor was 1.6, which is why any quoted figure needs its year attached. |
| ARL acceptable range | 1.6 – 3.6 |
| Ideal calcium level | 60 mg% (2008 onward), acceptable 22 – 97. The figure of 42 mg% is the retired 1985–93 value and should never be printed on its own as current. |
| Ideal phosphorus level | 16 mg%, acceptable 11 – 20. |
| Above 3.0 | Points to increased parathyroid and pancreatic activity as a trend. |
Worth noticing: Trace Elements revised its ideal calcium from 42 to 60 mg% and its ideal iron from 2.8 to 2.2, while the Ca/P ideal moved only from 2.63 to 2.6. The ratio held its position while the level underneath it changed by nearly half.
This part is settled and shared. A low Ca/P points to a sympathetic state; a high Ca/P points to a parasympathetic state. The work traces back to Melvin Page, DDS, and both traditions draw on that root.
Phosphorus is the volatile half of the pair — a key element in ATP, energy in motion. Calcium is structure. The ratio reads which side of the nervous system is currently running the show, expressed in two minerals.
Autonomic state is not autonomic dominance, and mixing them is the most common misreading of this ratio. Ca/P reads the state the body is in now. Na/K reads dominance — which branch a person actually lives in, with a Na/K above about 4 pointing to sympathetic dominance. The two can disagree on one chart. A Ca/P above 2.5 sitting next to a Na/K above 4 points to the burned-out sympathetic dominant pattern as a trend, and it is a common slow-oxidation picture.
One asymmetry matters. Either a high or a low phosphorus reading points to impaired protein synthesis, since all proteins carry phosphorus. But low phosphorus relative to calcium reads as the exhaustion end of the sequence, and is treated as the more consequential of the two directions.
Here is the divergence, stated plainly.
| Trace Elements (Watts) | Analytical Research Labs (Eck / Wilson) | |
|---|---|---|
| Framing of Ca/P | Autonomic: low sympathetic, high parasympathetic | Autonomic: low sympathetic, high parasympathetic |
| Position in the ratio table | First | Outside the core set |
| Weight given | Heavy — will move a client's metabolic pack from fast to slow, or slow to fast, on the strength of it | Read and reported, but the oxidation rate and the programme are not changed on it |
| Core ratios used to set type | Eight metabolic types, built gland by gland from the full ratio set | Four core ratios derived from ideal calcium, magnesium, sodium and potassium. Phosphorus sits outside that set entirely |
That last row is the mechanism. In the ARL system the oxidation rate is defined by exactly two ratios, Ca/K (ideal 4 to 4.2) and Na/Mg (ideal 4 to 4.17), and phosphorus appears in neither. Move the phosphorus and the ARL type does not move. In the Watts system the same shift can reclassify the person, and reclassification is what changes the pack. Two competent practitioners, one report, two programmes, and no contradiction between them. The mechanics of building the pack once a type is settled are covered in how a metabolic pack is assembled from a chart.
The split we work to is two recommendations rather than one. For the testing: Trace Elements, because more elements are reported and because Ca/P is actually applied to set the pack. For the interpretive ranges: the ARL guidelines, stricter because they are measured against an ideal standard of health rather than an average one. Narrower windows catch subtle deviations a wider range accepts. A Trace Elements report read against ARL ranges is the intended workflow, not an inconsistency. See the Trace Elements formulas we hand-select and the Endo-Met range.
Read gland by gland, these are the trends associated with Ca/P in the Trace Elements set. Every line is a tendency the chart points at, not a finding about a person.
| Reading | Trend indicated |
|---|---|
| Above 3.0 | Increased parathyroid activity; increased pancreatic (insulin) activity. Corroborated on the same chart by Ca/Mg above 13 to 14 and Ca/K above 4.2. |
| Above 2.63 | Decreased thyroid activity trend; increased ovarian oestrogen trend, particularly alongside a Zn/Cu below 8. |
| Below 2.63 | Increased thyroid activity trend; decreased parathyroid trend; catabolic adrenal dominance when it appears with Na/K below 1.8 and Ca/K below 4. |
| Phosphorus below 12 mg% | Read as impaired protein digestion or utilisation, or low dietary animal protein. On a report this is one of the trends commonly reviewed alongside dietary protein intake. |
Notice that no line in that table stands alone. Ca/P above 3.0 means one thing beside a high Ca/Mg and another beside a low Na/K, which is why the calcium and magnesium relationship and the position in the stress sequence get read in the same pass.
Ca/P moves because glandular activity moves the two minerals in opposite directions — parathyroid activity retains calcium and copper while excreting phosphorus, magnesium, chromium, sodium, potassium, iron and manganese. The ratio is downstream of that. Adding phosphorus to a chart with a high Ca/P addresses the arithmetic and leaves the reason alone.
The same logic runs the other way. A low Ca/P is a sympathetic, catabolic picture, and the response is built around the oxidation rate and the stress stage rather than around calcium as a number to be raised. This is the technical face of why I rarely give a mineral to raise that same mineral and the seesaw minerals.
On dosing: the amount on a bottle label is not the recommendation. Lab reports schedule formulas as 1-1-0 or 2-2-2 across morning, noon and evening, and the practitioner sets that from the report in front of them.
A Ca/P ratio is only as good as the hair it came from, and phosphorus is the element most sensitive to how the sample was taken.
Full instructions are on the sample collection page, and the test kit itself is here.
Curated by Practitioner Eileen Durfee, NBS (Nutritional Balancing Science), NASM-CPT — wellness educator, former nuclear quality engineer, inventor with 10 U.S. and 6 international patents
I came to hair analysis in 2010 under ARNP Julie Walker in Kennewick, Washington, and worked directly with Analytical Research Labs, testing family and friends while I learned to read charts. I listened to every cassette Dr. Paul Eck recorded and read every ARL newsletter. I signed up with Dr. Larry Wilson in August 2011, and I have practised independently since autumn 2017.
That path matters here, because I learned the ratios in ARL's vocabulary first, where Ca/P is a number you read and largely set aside. I learned the ratios in ARL's vocabulary first, and the Trace Elements set gives Ca/P a position at the top of the table that the ARL core set does not. My engineering years are what kept me on it until I worked it through: the measurement is shared, and the decision rule is not.
What I took from that is a habit. When a chart shows a Ca/P near the edge of the range, I read it against the stress stage and the oxidation ratios before it changes anything, and I want a second chart before treating a shift as a direction. One reading of a ratio this weighted is a snapshot. Two are a line.
This page covers the numbers and the decision rule. The companion pieces on EileenDurfee.com cover the principle underneath: why raising a mineral directly so rarely does what people expect.
The number does not tell you that on its own. Above 3.0 is read as a parathyroid and pancreatic activity trend, and what a programme does about it depends on the oxidation ratios, the Na/K and the Ca/Mg sitting beside it. Take the reading to whoever oversees your programme rather than acting on one figure.
Quite possibly neither. If one works from Trace Elements and the other from the ARL tradition, Ca/P is the likeliest place the readings split, because one system moves a metabolic pack on that ratio and the other does not. Ask each which ratios set your type. The answers usually explain the difference in a minute.
Diet is part of the picture, but the ratio mostly reflects glandular activity rather than what is on the plate, which is why phosphorus intake is not the lever people assume. The saying in this field is that diet is what is consumed and nutrition is what is retained and utilised. Ca/P sits on the retention side of that sentence.
Each reading averages roughly two to three months of hair growth, so a chart taken too soon is largely re-reading the period you already saw. Three to five months is the usual interval, and the direction across two or three charts carries far more information than any single value. More on timing on the retest page.
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.
Written by Eileen Durfee.
