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Phosphate is a mineral in your blood that you need for strong bones and teeth, for energy and for your nerves and muscles. A high level can point to kidneys that are not getting rid of excess phosphate properly. A low level can point to, for example, a lack of vitamin D or too little phosphorus from your food.[1]
On this page you can read what phosphate is, what the guidelines say about a low or high level, what affects your level and which values are best looked at alongside it.
Also known as: phosphorus, inorganic phosphorus, P. At the lab: PO4.
Phosphate contains the mineral phosphorus. It is an electrolyte: a mineral with an electric charge. Electrolytes help regulate the amount of fluid and the balance between acid and base in your body.[1]
Most of the phosphate in your body is in your bones, together with calcium. You get phosphorus from your food, such as nuts, seeds, dairy, dried beans, meat, poultry and eggs.[1]
Phosphate also goes by other names, such as phosphorus, inorganic phosphorus, P and PO4. So your result may say phosphorus or phosphate. Both mean the same thing.[1]
An abnormal phosphate level can point to a problem in the systems that regulate your phosphate. Think of your kidneys, your bones and your parathyroid glands, small glands in your neck.[1]
Too much phosphate can pull calcium out of your bones and make them weaker over time. It can also lower the calcium in your blood. That can cause symptoms such as muscle cramps, itching, brittle nails or an irregular heartbeat.[1]
A very low phosphate level can be life-threatening and needs a doctor straight away. Symptoms can include muscle pain or weakness, bone pain, and confusion or becoming irritable easily.[1]
The lab (Labplusarts) uses a reference value for phosphate (PO4) of 0.73 to 1.4 mmol/l. The lab calls a value between these limits normal.[2]
| Value | What the lab says | Who it is for |
|---|---|---|
| 0.73 to 1.4 mmol/l[2] | Normal according to the lab | Everyone tested at this lab |
Source: Labplusarts, reference value for phosphate (PO4). MedlinePlus does not give its own limits.[2]
A slightly low level is often not a problem for your health. A low level can point to parathyroid glands that make too much hormone, a lack of vitamin D or too little phosphorus from your food. Long-term use of certain antacids containing aluminium hydroxide or calcium carbonate can also lower your phosphate.[1]
A high level can point to kidneys that no longer filter excess phosphate properly, especially with advanced kidney disease. It can also point to parathyroid glands that make too little hormone, or to too much acid in your blood. Long-term use of certain medicines, such as steroids, or laxatives and enemas containing phosphate, can also raise your level.[1]
BioProfile is working on its own zones for each value, from risk to optimal. A doctor reviews those zones before they appear in your result.
Your phosphorus comes from your food. Your gut determines how much of it you absorb. Sometimes your healthcare provider asks you not to eat or drink for a few hours before the test.[1]
Certain medicines, vitamins and supplements can affect your result. So tell your healthcare provider about everything you take. Do not stop taking prescription medicines on your own.[1]
When your calcium rises, your phosphate usually falls, and the other way round. Vitamin D helps your body use phosphate. Parathyroid hormone keeps phosphate and calcium in balance.[1]
Your kidneys filter extra phosphate out of your blood and remove it through your urine. If your phosphate is low, they hold on to more of it. If your kidneys work less well, phosphate can build up.[1]
Phosphate is included in BioProfile 87, 121 and 150.[3]
The BioProfile editorial team wrote this page on 10 October 2026 from the sources below, which we read on 10 October 2026. Every number on this page appears in one of those sources, with that source's number next to it. An expert has yet to check this page; after that check, the expert's name and the date of the check will appear at the top. This page offers explanation, not a diagnosis. Discuss a value outside the range with your GP.
