Home
/
Markers
/
Liver
/
ALP (Alkaline Phosphatase)

Alkaline phosphatase: what your value means

You got your blood results back and there is an ALP on them. The number sits just outside the line. Alkaline phosphatase is an enzyme that comes mainly from your liver and your bones. That is the awkward part: the result itself does not reveal which of the two. This page answers the question you probably arrived with. What does this number mean, how high can it go, and what does your GP do next.

Doctor's Assessment Included

Reference Ranges

See the value that applies to you:

Age years

Choose male or female — this range differs by sex.

Enter your age — this range changes with age.

This range also depends on context such as cycle phase or sample material; the highlighted rows apply to your group.

Your reference range

u/l

38 209 u/l

Reference ranges by group, in u/l
Sex	Age	Reference range (u/l)	Relative scale
Male	· 13–18 years	63–190 u/l	63 190
Male	· 19–50 years	45–128 u/l	45 128
Male	· 51–65 years	46–126 u/l	46 126
Male	· 66–80 years	44–134 u/l	44 134
Male	· 81 years and older	45–145 u/l	45 145
Female	· 6–12 years	107–209 u/l	107 209
Female	· 13–18 years	44–149 u/l	44 149
Female	· 19–50 years	38–123 u/l	38 123
Female	· 51–65 years	48–142 u/l	48 142
Female	· 66–80 years	47–138 u/l	47 138
Female	· 81 years and older	45–146 u/l	45 146

38 209 u/l

Source: NVKC Reference population: Nederlandse huisartsenpopulatie (NUMBER, n=7.574.327)

Reference ranges may vary between laboratories. When you order a test, a BIG-registered doctor assesses your personal results in context. For treatment decisions, discuss your results with your GP.

Check your own value

ALP (Alkaline Phosphatase): what this test measures

The test measures how much alkaline phosphatase is active in your blood, in u/l. Alkaline phosphatase is an enzyme almost all your tissues make. The test adds all those forms together. They are not measured separately, and that is where the whole ambiguity comes from.

You will see two spellings on reports. AF is the Dutch abbreviation and ALP the international one. They mean the same test.

The normal value depends heavily on your age and your sex. That is not sloppiness on the lab's part. The more active your bones, the higher the number. A teenager in the growth spurt sits well above an adult ceiling, and that is normal.

Who you are	Reference value in u/l
Man, 19 to 50	45 to 128
Woman, 19 to 50	38 to 123
Man, 51 to 65	46 to 126
Woman, 51 to 65	48 to 142
Man, 81 and older	45 to 145
Woman, 81 and older	45 to 146

These figures come from NUMBER, the national harmonisation project run by the NVKC. Look closely at the last two rows.

A value of 145 falls inside the band for a man of eighty. For a man of thirty it falls outside. Age changes what the same number means.

Your own laboratory may use slightly different limits. The reference on your own report always takes precedence.

ALP (Alkaline Phosphatase): why this value matters

The meaning of alkaline phosphatase is not in the number itself. It is in the question it asks: did this come from your liver or from your bones. Until you know that, the result gets you very little.

Your GP almost always resolves it the same way. They look at your gamma-GT. That enzyme sits in your liver and bile ducts, but not in bone. That turns it into a kind of switch.

If alkaline phosphatase and gamma-GT are both high, your doctor looks towards your liver or bile ducts. If only alkaline phosphatase is raised and gamma-GT is normal, it probably comes from your bones. Or it is not a problem at all.

That last case happens more often than people expect. Raised values belong with growth and with pregnancy. A healing fracture lifts them too. So can a fatty meal shortly before the draw.

The second step is often simpler than you expect. Many GPs simply repeat the test after a few weeks. A one-off mild abnormality says little, and a second measurement shows whether it stays. If it disappears, the story usually ends there.

What your result does not say is how serious something is. The height of the number does not track the seriousness of the cause. So read it alongside your ALT and your direct bilirubin.

ALP (Alkaline Phosphatase): when is testing worthwhile?

Usually you did not request this test yourself. Alkaline phosphatase sits in almost every liver panel as standard. It simply came out with the rest.

Asking for it deliberately makes sense in a few cases. With itching without a rash, or with yellowing of your skin or eyes. With dark urine or pale stools. And with bone pain that does not fit an injury you know about.

Never request it on its own. Without gamma-GT beside it you cannot place a raised result. You end up with a number that points nowhere. The other liver values belong with it.

Do you need to fast? For this test alone, usually not. Fasting is still smart here. The intestinal form of the enzyme rises for a few hours after a fatty meal.

Blood groups O and B are where that shows up most. It is a harmless explanation for a mildly raised result. You would simply rather not have it in your measurement.

If other values are drawn at the same time, follow the instructions for that test.

ALP (Alkaline Phosphatase): symptoms of a high or low value

Low Levels

You will not notice a low value. It almost always turns up by chance, and usually there is nothing behind it.

Even so, low is not automatically good news, which is exactly why this section is here.

If your value stays low on repeat testing, a zinc or magnesium deficiency may be in play. An underactive thyroid and severe malnutrition are on that list too. Rarer are Wilson's disease and hypophosphatasia, an inherited condition in which the enzyme itself works poorly.

One low result without symptoms need not occupy you. If it comes back low twice, put it to your GP.

High Levels

Most people with a mildly raised value feel nothing at all. That is the ordinary course, not the exception.

Where there are symptoms, they often give away the source. If it comes from your bile ducts, you get itching without a rash.

Yellowing of skin or the whites of the eyes belongs here too. So do dark urine and pale stools. Sometimes pain in the upper right of your abdomen comes with it.

If it comes from your bones, the picture is different. Then it is bone pain that carries on at night. Or a bone changing shape. Or a fracture after a fall that was really too light.

One thing matters more than the list itself. How high the number sits says little about how serious the cause is.

ALP (Alkaline Phosphatase): what to do about an abnormal value

Male

If Low

Low ALP is generally not concerning.

If High

Elevated ALP may indicate bile duct or bone problems. Consider further evaluation.

Female

If Low

Low ALP is generally not concerning.

If High

Elevated ALP may indicate bile duct or bone problems. Consider further evaluation.

ALP (Alkaline Phosphatase): lifestyle and this value

You cannot steer this number down directly, and saying so is more honest than pretending otherwise. What you can do is help the two tissues the enzyme comes from.

For your liver and bile ducts: keep alcohol limited and work towards a healthy weight. Take medication as prescribed. If you have been on something long term, mention it. Drug-induced cholestasis is a real cause, and often a reversible one.

For your bones: get enough vitamin D and calcium. Move in ways that make you carry your own weight. Walking, stairs and strength training all count.

And three things to avoid. Do not start high-dose vitamin D yourself because of this result alone. The source has to be clear first.

Do not leave an abnormal value sitting for years. And do not draw a conclusion from one measurement.

Going for another draw? Choose a fasting sample, on a day without heavy training.

ALP (Alkaline Phosphatase): frequently asked questions

What does a raised alkaline phosphatase say?

On its own, mainly that there is something to look into. The enzyme comes from your liver and from your bones, and the test adds both sources together. Only next to gamma-GT does it become clear which way it points.

What is the normal value of alkaline phosphatase?

That depends on your age and sex. According to NUMBER the band for men aged 19 to 50 runs from 45 to 128 u/l. For women of that age it runs from 38 to 123 u/l. Above fifty both bands rise again.

How high may the ALP value be?

The ceiling shifts with age. For an adult man under fifty it sits around 128 u/l. For a man over eighty it sits around 145 u/l. That is why the same number can be normal for one person and not for another.

My value reads 145, is that too high?

That depends entirely on who you are. For a man of eighty, 145 falls inside the reference band. For a man of thirty it falls outside. So compare your result against the row for your own age and sex on your own report.

What does my GP do if the ALP value in blood is too high?

Usually two things. First they place your result beside gamma-GT and the other liver values. That separates liver from bone. A repeat after a few weeks often follows, to see whether the rise persists.

Can I do anything myself to lower the value?

Not directly. You can support the sources: less alcohol and a healthy weight. Get enough calcium and vitamin D, and take exercise where you carry your own weight. Do not start high-dose supplements on your own initiative.

Test Products

This marker is included in the following test panels.

Health Checkups

Complete Metabolic Panel

Comprehensive metabolic panel: electrolytes, kidney, liver, glucose, HbA1c, and protein.

Bicarbonate Calcium Chloride Potassium Sodium Glucose (Fasting) HbA1c (Glycated Hemoglobin) Albumin ALP (Alkaline Phosphatase) ALT (Alanine Aminotransferase) AST (Aspartate Aminotransferase) Bilirubin (Total) Urea (BUN) Creatinine eGFR (Estimated Glomerular Filtration Rate) Total Protein

€149,-

Whoop

A 43-biomarker comprehensive health panel inspired by WHOOP Advanced Labs — a deep look at metabolism, cardiovascular risk, hormones, liver, kidney and inflammation.

SHBG (Sex Hormone Binding Globulin) TSH (Thyroid Stimulating Hormone) ALT (Alanine Aminotransferase) LDL Cholesterol Cortisol DHEA-S Estradiol (E2) Free Testosterone FSH (Follicle Stimulating Hormone) LH (Luteinizing Hormone) Total Testosterone Bicarbonate Calcium Chloride Ferritin Iron (Serum) Magnesium Potassium Sodium Transferrin CRP (C-Reactive Protein) Homocysteine Glucose (Fasting) HbA1c (Glycated Hemoglobin) ApoB (Apolipoprotein B) HDL Cholesterol Total Cholesterol Albumin HOMA-IR ALP (Alkaline Phosphatase) AST (Aspartate Aminotransferase) Bilirubin (Total) Total Protein Urea (BUN) Creatinine Vitamin D (25-OH) eGFR (Estimated Glomerular Filtration Rate) Insulin (Fasting) Leukocyte Differential Transferrin Saturation Lipoprotein(a) Triglycerides Basic Blood Count

€499,-

Whoop

Whoop Heart Health

A 45-biomarker heart health panel inspired by the WHOOP Heart Health Panel — an advanced look at cholesterol, lipoproteins, inflammation and kidney function.

Complete Blood Count (CBC) Leukocyte Differential ALP (Alkaline Phosphatase) ALT (Alanine Aminotransferase) AST (Aspartate Aminotransferase) Albumin Total Protein Bilirubin (Total) ApoB (Apolipoprotein B) Total Cholesterol LDL Cholesterol HDL Cholesterol Triglycerides Lipoprotein(a) Urea (BUN) Creatinine eGFR (Estimated Glomerular Filtration Rate) Calcium Bicarbonate Chloride Sodium Potassium Magnesium Cortisol DHEA-S Estradiol (E2) FSH (Follicle Stimulating Hormone) LH (Luteinizing Hormone) SHBG (Sex Hormone Binding Globulin) Total Testosterone Free Testosterone TSH (Thyroid Stimulating Hormone) Glucose (Fasting) HbA1c (Glycated Hemoglobin) Insulin (Fasting) HOMA-IR CRP (C-Reactive Protein) Homocysteine Ferritin Iron (Serum) Transferrin Transferrin Saturation Vitamin D (25-OH) Cystatin C Uric Acid

€629,-

Whoop

Whoop Performance Health

A 50-biomarker performance panel inspired by the WHOOP Performance Health Panel — recovery, blood production, thyroid, hormones, iron and nutrient status for people who train.

€689,-

Whoop

Whoop Metabolic Health

A 51-biomarker metabolic panel inspired by the WHOOP Metabolic Health Panel — blood sugar regulation, insulin, thyroid, liver and the mineral cofactors behind your metabolism.

€799,-

Whoop

Whoop Women's Health

A 53-biomarker women's health panel inspired by the WHOOP Women's Health Panel — fertility, cycle and thyroid hormones plus a complete metabolic and nutrient base.

€709,-

Whoop

Whoop Men's Health

A 48-biomarker men's health panel inspired by the WHOOP Men's Health Panel — testosterone, PSA and prostate health plus a complete metabolic and hormone base.

€659,-

Medical standards

Dr. Naimi oversees the medical standards behind our content and assessments.

Medical policy

CIBG Ministerie van Volksgezondheid,
Welzijn en Sport Official BIG registration BIG 49928676701

Doctor's Assessment Included

Every result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.

ALP (Alkaline Phosphatase)

€8,-

Reference Ranges

ALP (Alkaline Phosphatase): what this test measures

ALP (Alkaline Phosphatase): why this value matters

ALP (Alkaline Phosphatase): when is testing worthwhile?

ALP (Alkaline Phosphatase): symptoms of a high or low value

Low Levels

High Levels

ALP (Alkaline Phosphatase): what to do about an abnormal value

Male

Female

ALP (Alkaline Phosphatase): lifestyle and this value

ALP (Alkaline Phosphatase): frequently asked questions

Test Products

Complete Metabolic Panel

Whoop

Whoop Heart Health

Whoop Performance Health

Whoop Metabolic Health

Whoop Women's Health

Whoop Men's Health

Read more about this blood value

Getting liver values tested: how a liver function test works

Gamma-GT too high: causes and what it means

Understanding liver values: ALAT, ASAT and gamma-GT

Medical standards