What is phosphate?
Phosphate sits mostly in your bones and teeth, where it forms the hard structure together with calcium. The rest works in your cells: it is the building block of ATP, the molecule with which every cell passes energy on, and of your genetic material and your cell membranes. In your blood only a small part circulates, and that part is what is measured. How much stays in your blood is regulated by three players together. Your kidneys excrete what you take in too much of. PTH, the hormone of the parathyroid glands, sets the kidneys to excreting more. Vitamin D raises the uptake from the gut. In that system phosphate is the value that usually moves as a consequence: if it rises, it is usually the kidneys that can get rid of less; if it falls, it is usually PTH pulling too hard or vitamin D letting too little in. Your report shows phosphate in mmol/L, often with a range for men and for women that differs slightly. Normal in a man from age 19 is 0.81 to 1.32 mmol/L and in a woman 0.81 to 1.40 mmol/L where the labs overlap; one lab starts lower, and the national agreement uses a slightly higher range, 0.9 to 1.5 mmol/L. A value just under 0.9 is therefore not called the same everywhere.
Why is phosphate relevant?
For anyone healthy who eats healthily, phosphate is a value that rarely moves: you get plenty of it, from meat, dairy, fish, nuts and grains, and your kidneys excrete the surplus. It becomes interesting when the kidneys filter less. Then phosphate slowly accumulates, the parathyroid glands respond with more PTH, and that pulls calcium out of bone. In chronic kidney disease phosphate is therefore one of the values followed, and a high phosphate there goes with a higher chance of calcification of the vessels. That is also where the lifestyle side sits. Phosphate from natural food is only half absorbed; phosphate from additives in processed food, cola, processed cheese, processed meat and ready meals is absorbed almost completely. Anyone who eats a lot of processed food takes in a phosphate load that healthy kidneys can handle, but that counts with weaker kidneys and with age. Less processed food is the lever, and that is the same lever as for blood pressure and weight. A low phosphate in healthy people is the other side of the same system: a vitamin D deficiency, which lets too little phosphate in, or too much PTH, which sends too much into the urine. Alcohol, eating too little and rapid refeeding after a period of eating little push it down too, because the cells then take up phosphate to make energy again.
Phosphate reference ranges
What counts beside the number:
- Creatinine and eGFR, because a high phosphate is usually a kidney value
- Calcium and PTH, which show which way the system is pulling
- Vitamin D, the most common reason for a low phosphate
- How much processed food, cola and processed cheese you eat
- Alcohol, eating too little and antacids
- Your own lab's range, because the floor differs per lab and the national agreement sits slightly higher
The bands above are where the labs overlap; the range on your own report is usually wider at the bottom, and the national agreement sits slightly higher instead. A slightly low value in a healthy person is therefore often a matter of which limit you use, and not of your phosphate. Phosphate is above all a kidney value: read it beside calcium, PTH, vitamin D and your kidney function.
What Dutch labs actually use
Phosphate is the only value in this group where a national figure exists and that figure is at odds with all four labs. The Dutch primary-care laboratory agreement publishes 0.9 to 1.5 mmol/L. All four labs set their adult floor lower: Clinical Diagnostics at 0.81, Certe at 0.71 and 0.76, and Unilabs and Star-shl both at 0.62 for men and 0.73 for women. That means a value of 0.81 mmol/L falls inside the reference range at every Dutch laboratory and below the only national figure at the same time. Neither is wrong; they describe different things, just as with LDH, where the same collision runs the other way. Certe is also the only lab that splits adult men by age, and that band gets narrower after forty-nine rather than wider: from 0.71 to 1.53 down to 0.71 to 1.23. And only at Star-shl and Unilabs does the women's band sit above the men's.
0.81 – 1.40mmol/L
Between 0.73 and 0.81 and between 1.40 and 1.45 it depends on the lab, because each sets its limits on its own method and population. Above 1.45 every lab calls it abnormal.
every lab calls 0.81 – 1.40 mmol/L normal. Between 0.73 and 0.81 and between 1.40 and 1.45 it depends on the lab.
Every age, per lab
| Laboratory | Group | Reference range |
|---|---|---|
| Unilabs(Saltro, Medlon, SHO, Atalmedial)2026 | Women 13 to 18 yrs | 0.82–1.52 mmol/L |
| Men 13 to 18 yrs | 0.88–1.53 mmol/L | |
| Women from 19 yrs | 0.73–1.40 mmol/L | |
| Men from 19 yrs | 0.62–1.32 mmol/L | |
| Star-shl2026 | Women 13–18 yrs | 0.82–1.52 mmol/L |
| Men 13–18 yrs | 0.88–1.53 mmol/L | |
| Women from 18 yrs | 0.73–1.40 mmol/L | |
| Men from 18 yrs | 0.62–1.32 mmol/L | |
| Certe2026 | Women 13–16 yrs | 1.02–1.81 mmol/L |
| Men 13–16 yrs | 1.14–2.01 mmol/L | |
| Women 16–18 yrs | 0.95–1.63 mmol/L | |
| Men 16–18 yrs | 0.95–1.63 mmol/L | |
| Women from 18 yrs | 0.76–1.41 mmol/L | |
| Men 18–49 yrs | 0.71–1.53 mmol/L | |
| Men from 49 yrs | 0.71–1.23 mmol/L | |
| Clinical Diagnostics2026 | Adults | 0.81–1.45 mmol/L |
Each band as the lab publishes it, retrieved in 2026, unless marked otherwise.
Phosphate high or low: what it means
A high phosphate comes, in order of how often it occurs, from: reduced kidney function, which cannot get rid of the surplus; plenty of phosphate additives from processed food, cola and processed cheese; too little PTH, after surgery in the neck; and rarely rapid cell breakdown or an excess of vitamin D. With a high value kidney function is the first look, and what you eat the second. A low phosphate comes from too little uptake or too much excretion: a vitamin D deficiency, a parathyroid gland making too much PTH, plenty of alcohol, eating too little or rapid refeeding afterwards, antacids that bind phosphate in the gut, and rarely an inherited leak in the kidney. A slightly low value in a healthy person is often simply the lab's floor, or a meal shortly before; phosphate fluctuates over the day. What you do about it: with a high value and weaker kidneys less processed food, cola and processed cheese, and protein from natural sources; with a low value top up vitamin D if that deficiency is there, less alcohol, and enough food. Phosphate as a supplement is rarely needed and unwise without reason. Read phosphate beside calcium, PTH, vitamin D and your kidney function. The order that helps: first the kidneys, then calcium, then PTH; in that system phosphate is usually the consequence and rarely the cause.
What lowers it
Too little uptake or too much excretion; in a healthy person often the lab's floor.
| Cause | How often |
|---|---|
| A vitamin D deficiencyVitamin D lets phosphate and calcium be absorbed from the gut; with a deficiency phosphate falls and PTH rises | Often |
| Too much PTHPTH sends phosphate into the urine; a parathyroid gland making too much gives a low phosphate beside a high calcium | Sometimes |
| Plenty of alcohol, eating too little or rapid refeedingAlcohol and malnutrition deplete the store, and with rapid eating again the cells pull phosphate inside to make energy | Sometimes |
| Antacids with aluminium or magnesiumBind phosphate in the gut, so that it is not absorbed | Rare |
What raises it
Usually the kidneys, which cannot get rid of the surplus, and what you eat.
| Cause | How often |
|---|---|
| Reduced kidney functionKidneys that filter less excrete less phosphate; it slowly accumulates and the parathyroid glands respond with more PTH | Often |
| A high phosphate intake from foodAbove all phosphate additives in processed food, cola, processed cheese and processed meat, which are absorbed almost completely; healthy kidneys excrete it, weaker ones do not | Sometimes |
| Too little PTHWithout PTH the kidneys excrete less phosphate; usually after surgery in the neck, with a low calcium beside it | Rare |
| Rapid cell breakdown or too much vitamin DWhen many cells break down at once phosphate is released, and an excess of vitamin D lets too much be absorbed | Rare |
How does a phosphate blood test work?
- Referral
- Not needed. You can have phosphate measured without going through your GP.
- Fasting
- Preferably yes, or at least always the same way: phosphate fluctuates over the day and dips temporarily after a carbohydrate-rich meal.
- The draw
- One tube of blood from a vein in your arm, usually together with calcium, PTH, vitamin D and creatinine.
- The result
- A single number in mmol/L, often with a range for men and for women; usually available the same day.
- Where to draw
- You can draw at 250+ locations near you, no referral needed. See the locations
Frequently asked questions
What is phosphate?
A mineral that builds your bones and teeth together with calcium and that passes energy on in every cell, as part of ATP. In your blood only a small part circulates, and how much that is, your kidneys, PTH and vitamin D regulate together. That makes phosphate above all a value that moves as a consequence: of the kidneys, of the parathyroid glands or of vitamin D.
What is a normal phosphate level?
In a man from age 19, 0.81 to 1.32 mmol/L and in a woman 0.81 to 1.40 mmol/L, where the labs overlap. Most labs start lower, and the national agreement uses 0.9 to 1.5 mmol/L. A value just under 0.9 is therefore called normal at one lab and low by the national figure; in a healthy person that is rarely anything to worry about.
What does a high phosphate mean?
Usually that your kidneys cannot get rid of the surplus: with reduced kidney function phosphate slowly accumulates, and the parathyroid glands respond with more PTH. Processed food with phosphate additives, cola, processed cheese and processed meat lifts the value too, because that phosphate is absorbed almost completely. Rarely it is too little PTH, after surgery in the neck, or rapid cell breakdown. Kidney function is the first look.
What does a low phosphate mean?
Too little uptake or too much excretion: a vitamin D deficiency, a parathyroid gland making too much PTH, plenty of alcohol, eating too little or rapid refeeding afterwards, and antacids that bind phosphate in the gut. A slightly low value in a healthy person is often the lab's floor or a meal shortly before, because phosphate fluctuates over the day. Measure again fasting first.
What does processed food have to do with phosphate?
Phosphate from natural food, meat, dairy, nuts and grains, is only half absorbed. Phosphate from additives in processed food, cola, processed cheese, processed meat and ready meals is absorbed almost completely. Healthy kidneys excrete that surplus; with weaker kidneys and with age it counts and goes with a higher chance of calcification of the vessels. Less processed food is the lever.
Why does the national value sit higher than the labs' values?
Because the sources measured different groups and drew their limit differently; neither is wrong. What counts for you: a value between your lab's floor and 0.9 mmol/L is not a finding in a healthy person, and a value that is genuinely low comes with a cause you find back in vitamin D, PTH or your eating pattern.
Why is phosphate determined together with calcium and PTH?
Because the three form one regulatory system, with vitamin D and the kidneys included. PTH pulls calcium out of bone and sends phosphate into the urine, vitamin D lets both be absorbed from the gut, and the kidneys excrete the surplus. A single phosphate value therefore says little; beside calcium and PTH you see which way the system is pulling and what the cause is.
Do I need to fast?
Preferably yes, or at least always the same way: phosphate dips temporarily after a carbohydrate-rich meal and fluctuates over the day. Have calcium, PTH, vitamin D and creatinine taken from the same draw.
Which tests include phosphate?
Phosphate is part of Advanced, the broader panel. It is not orderable yet.
Related biomarkers
Sources
- 1.Unilabs, test catalogue (Dutch): phosphate. 2026. bepalingenklapper.nl
- 2.Star-shl, test catalogue (Dutch): inorganic phosphate. 2026. star-shl.nl
- 3.Certe, test catalogue (Dutch): phosphate. 2026. bepalingenwijzer.certe.nl
- 4.Clinical Diagnostics, lab guide (Dutch): phosphate. 2026. clinicaldiagnostics.nl
- 5.LESA Laboratory diagnostics (Dutch primary-care laboratory agreement). 2026. richtlijnen.nhg.org
- 6.NHG guideline on chronic kidney disease (M109), Dutch College of General Practitioners. 2026. richtlijnen.nhg.org
- 7.Dutch chronic kidney disease guideline: secondary hyperparathyroidism. 2026. richtlijnendatabase.nl
Educational information only, not medical advice. Consult a healthcare professional for clinical decisions.
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Phosphate is part of Advanced, the broader panel. It is not orderable yet.
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