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Immunity & Inflammation

Neutrophils

Neutrophils are the largest group of white blood cells and the first on the scene at a bacterium or a wound. The count rises with a bacterial infection, stress, exercise and smoking, and falls after a virus or through medicines.

Medically reviewed by
Aäron Spapens
Aäron Spapens
Lifestyle physician at Optimize

In short

Healthy is a count between 1.8 and 7.0 ×10⁹/L, where the labs overlap, and for a non-smoker preferably in the lower half; below 1.5 ×10⁹/L the defence against bacteria gets thinner, and below 0.5 ×10⁹/L fever is an emergency.

  • A low count is usually a virus that has just passed or a medicine, and in many people with African or Middle Eastern ancestry simply make-up; it weighs more heavily than a high count because the defence against bacteria gets thinner.
  • A high count with fever and a high CRP is a bacterial infection; without fever it is almost always stress, yesterday's training, smoking or prednisone, and those lift the count without anything being wrong.
  • Read the absolute count and not the percentage, and always beside the lymphocytes and CRP: together they say whether it is a bacterium or a virus.
On this page7

What are neutrophils?

Of all white blood cells, neutrophils are the most numerous: more than half of what your blood count tallies. They are the first responders. They live only a day, are made in your bone marrow in enormous numbers, and move within minutes to the place where a bacterium enters or tissue is damaged. There they swallow bacteria and destroy them with enzymes and oxygen radicals. Pus is largely dead neutrophils. Because they live so briefly, the count in your blood is a snapshot of supply and demand. Your bone marrow keeps a large reserve ready, and part of the cells sit stuck to the wall of your blood vessels rather than flowing along. Adrenaline loosens them: with stress, a hard training session or a fright the count doubles within an hour and is back a few hours later. Cortisol and prednisone do the same, and keep the cells in the blood longer as well. A bacterial infection sets the bone marrow to extra production, and then young forms appear in your blood too. Your report shows the count in ×10⁹/L, and read it as an absolute count, not as a percentage. Normal is about 1.8 to 7.0 ×10⁹/L, where the labs overlap. Below 1.5 ×10⁹/L the defence against bacteria gets thinner, and below 0.5 ×10⁹/L an ordinary infection is an emergency.

Why are neutrophils relevant?

Neutrophils are the value that says whether an infection is bacterial. A bacterium lifts the count, with a high CRP alongside and often young forms on the report; a virus leaves the neutrophils normal or low and lifts the lymphocytes. That difference is the reason a blood count with differential says more than the total of white cells, and it is the question a doctor answers before deciding on antibiotics. Outside an infection, neutrophils say something about the state of your body. Smoking keeps the lungs in a light inflammatory state and lifts the count persistently, belly fat does so more mildly, and poor sleep and chronic stress through cortisol. A count that sits against the upper bound year after year without you being ill is therefore a sign of smouldering inflammation, and it goes with more cardiovascular disease. It is also the numerator in the ratio with lymphocytes, the NLR, which measures exactly that balance between stress and recovery. A low count is the side that counts for your safety. Most falls are harmless: a virus that has just passed, a medicine, or a make-up that is common in people with African or Middle Eastern ancestry and in which the immune system simply works. But below 0.5 ×10⁹/L your body has hardly any defence against bacteria, and fever is then a reason to be seen the same day. That is why a low count is phoned through and a high one not.

Neutrophils reference ranges

What counts beside the number:

  • The absolute count, not the percentage, because that also shifts when another type moves
  • The lymphocytes from the same draw: neutrophils up is a bacterium, lymphocytes up a virus
  • CRP, which says whether inflammation is running or stress or exercise lifted the count
  • Whether you trained hard the day before, whether you smoke and which medicines you take
  • Your ancestry, because a count around 1.0 to 1.5 is make-up in many people
  • With a low count: haemoglobin, platelets, B12 and folate
Neutrophils reference ranges
GroupReference range
AdultsWhere the four labs overlap; the upper bound runs from 7.0 to 7.5 and there they agree strikingly well1.8–7.0 ×10⁹/L
Unilabs telephones throughHere your body has hardly any defence against bacteria, and fever is an emergency Unilabs< 0.5 ×10⁹/L
Clinical Diagnostics telephones throughHere the defence against bacteria gets thinner; in people with a naturally lower count this is often their usual state Clinical Diagnostics< 1.5 ×10⁹/L
Above age 15The national band; slightly wider at both ends than where these four labs meet LESA Laboratory diagnostics1.5–7.5 ×10⁹/L

Read neutrophils as an absolute count, not as a percentage of the white cells, because a percentage also shifts when another type moves. A count just below the band is make-up in many people with African or Middle Eastern ancestry, with an immune system that simply works. Yesterday's training and today's stress sit in your blood for a few hours, so a calm morning gives your true value.

What Dutch labs actually use

These four labs agree strikingly well about the ceiling: 7.0 at Certe, 7.3 at Star-shl, 7.5 at Unilabs and Clinical Diagnostics. Where they part company is over when a low number counts as an alarm. Unilabs telephones a count through only below 0.5; Clinical Diagnostics already does so below 1.5. The same value of 1.2 sets the phone ringing at one lab and not at the other.

Adults · every lab calls this normal

1.8 – 7×10⁹/L

Between 1.5 and 1.8 and between 7 and 7.5 it depends on the lab, because each sets its limits on its own method and population. Above 7.5 every lab calls it abnormal.

Unilabs(Saltro, Medlon, SHO, Atalmedial)
1.5–7.5 ×10⁹/L
1.8–7.3 ×10⁹/L
1.8–7 ×10⁹/L
1.5–7.5 ×10⁹/L

every lab calls 1.8 – 7 ×10⁹/L normal. Between 1.5 and 1.8 and between 7 and 7.5 it depends on the lab.

Every age, per lab
What Dutch labs actually use
LaboratoryGroupReference range
Unilabs(Saltro, Medlon, SHO, Atalmedial)2026Above 15 yrs1.5–7.5 ×10⁹/L
Call-back limit< 0.5 ×10⁹/LDecision limit
Star-shl2026All ages1.8–7.3 ×10⁹/L
Certe2026Women from 18 yrs1.8–7 ×10⁹/L
Men from 18 yrs1.8–7 ×10⁹/L
Clinical Diagnostics2026Above 15 yrs1.5–7.5 ×10⁹/L
Call-back limit< 1.5 ×10⁹/LDecision limit

Each band as the lab publishes it, retrieved in 2026, unless marked otherwise.

Neutrophils high or low: what it means

A low count usually means the bone marrow is temporarily making less or cells have been drawn into the tissue. From common to rare: a viral infection in the past weeks, which keeps the count low for up to a few weeks; medicines, such as some painkillers, antibiotics, thyroid blockers, drugs for rheumatoid arthritis, epilepsy or psychosis; and make-up, in which the count sits around 1.0 to 1.5 without you being ill more often. Rarer are a B12 or folate deficiency, which makes the bone marrow slower at all cells, and an autoimmune disease. A count that keeps falling without explanation, or falls together with anaemia and few platelets, should be investigated. A high count means your body is mobilising neutrophils. With fever and a high CRP it is a bacterial infection or tissue damage, and then the count falls with recovery. Without fever it is almost always something else: a hard training session the day before, stress, smoking, prednisone, a pregnancy or belly fat. The difference sits in the young forms: with an infection the bone marrow releases immature cells, with stress only mature cells from the vessel wall. A count far above the band with immature cells alongside is a different picture, and a doctor assesses that the same day. What you do about it: with a high count from an infection nothing, and with a count that stays at the high end without an infection, stopping smoking is the biggest step, followed by less belly fat, better sleep and less chronic stress. Have blood drawn on a rest day, because yesterday's training is in your blood today. With a low count from a medicine the question is whether that medicine stays necessary, and that is a conversation with whoever prescribed it. With a B12 or folate deficiency the bone marrow recovers as soon as you top up. Set neutrophils beside the lymphocytes, because together they show whether it is a bacterium or a virus, beside CRP, which says whether inflammation is running, and beside the total of white cells. With a low count, haemoglobin, platelets and B12 and folate belong with it too.

What lowers it

The bone marrow is temporarily making less, cells have been drawn into the tissue, or your count is naturally lower.

What lowers it: Neutrophils
CauseHow often
Viral infectionA virus slows production for a few days and draws cells out of the blood; the count stays low for up to a few weeks and recovers by itselfOften
MedicationSome painkillers, antibiotics, thyroid blockers and drugs for rheumatoid arthritis, epilepsy or psychosis suppress productionOften
A naturally lower countIn many people with African or Middle Eastern ancestry the count sits around 1.0 to 1.5, with an immune system that simply worksSometimes
B12 or folate deficiencyThe bone marrow makes all cells more slowly; then the MCV is usually raised and haemoglobin lowered as wellRare
Autoimmune diseaseIn lupus or rheumatoid arthritis antibodies can break down neutrophils; then there are usually symptoms and other abnormalities tooRare

What raises it

Your body is mobilising neutrophils, from the bone marrow or from the vessel wall, and with or without fever makes the difference.

What raises it: Neutrophils
CauseHow often
Bacterial infectionThe classic reason: the bone marrow releases extra cells, young forms appear in the blood and CRP rises alongOften
Hard exercise shortly beforehandAdrenaline loosens cells from the vessel wall; the count doubles within an hour and is back a few hours laterOften
CorticosteroidsPrednisone releases cells from the bone marrow and keeps them in the blood longer; during a course the count sits high without an infectionOften
Tissue damageAn operation, an injury, a burn or a heart attack give the same response as a bacteriumSometimes
SmokingSmokers have persistently more neutrophils; after stopping, the count falls over monthsSometimes
Bone marrow diseaseWith a count far above the band, with immature cells on the report, the bone marrow is making cells uncontrolledRare

How does a neutrophils blood test work?

Referral
Not needed. Neutrophils are in every blood count with differential, and you can have that measured yourself.
Fasting
Not needed; the count does not respond to food. It does respond to exertion and stress, so come to the draw calmly.
When
On a rest day, not the morning after a hard training session, and not during or in the weeks after an infection if you want to know your usual level.
The draw
One tube of blood from a vein in your arm. The lab counts the white cells and sorts them into five types; CRP can come from the same draw.
Repeating
With a low count after two to four weeks, to see whether it was a virus that passed. With a low count from make-up one repeat is enough; after that it need not be more often than once a year.
Which test
Neutrophils is in the comprehensive test (€229) and in .
Where to draw
You can draw at 250+ locations near you, no referral needed. See the locations

Frequently asked questions

What are neutrophils?

The largest group of white blood cells and the first responders of your immune system. They live only a day, are made in your bone marrow in enormous numbers, and move within minutes to a bacterium or damaged tissue, where they swallow bacteria and destroy them. Pus is largely dead neutrophils. The count in your blood is a snapshot of supply and demand.

What is a normal neutrophil value?

Between 1.8 and 7.0 ×10⁹/L, where the four labs overlap. A non-smoker usually sits in the lower half. In many people with African or Middle Eastern ancestry the count naturally sits around 1.0 to 1.5, and for them that is healthy. Read the absolute count, not the percentage, and measure on a calm morning, because exertion and stress lift the count for a few hours.

What does a high neutrophil count mean?

That your body is mobilising neutrophils. With fever and a high CRP it is a bacterial infection or tissue damage, and then young forms appear in your blood. Without fever it is almost always something else: a hard training session the day before, stress, smoking, prednisone, a pregnancy or belly fat, and then it is mature cells that have been loosened from the vessel wall. A count far above the band with immature cells alongside is assessed the same day.

What does a low neutrophil count mean?

Usually that a virus has just passed or that a medicine is slowing production, and that recovers by itself over weeks. In many people a lower count is simply make-up. The count matters for your safety: below 1.5 ×10⁹/L the defence against bacteria gets thinner, and below 0.5 ×10⁹/L fever is a reason to be seen the same day. If the count keeps falling without explanation, or haemoglobin and platelets fall along, then an investigation belongs with it.

Why is my count low while I am never ill?

Because a lower count is make-up in many people. In people with African or Middle Eastern ancestry an inherited variant is common in which more neutrophils sit against the vessel wall and fewer flow along; the blood count then tallies around 1.0 to 1.5, while the cells are there and the immune system simply works. One repeat showing the same is enough to record this as your usual state.

Why is my count high after training?

Because adrenaline loosens neutrophils from the vessel wall, where part of the cells sit stuck rather than flowing along. Within an hour of a hard effort the count can double, and a few hours later it is back. They are mature cells, not a sign of infection, and CRP stays normal. So have blood drawn on a rest day if you want to know your usual level.

How do I tell a bacterium from a virus?

By the ratio between neutrophils and lymphocytes. A bacterium lifts the neutrophils, with young forms on the report and a high CRP. A virus leaves the neutrophils normal or low and lifts the lymphocytes, with a CRP that rises only a little. That is why a blood count with differential says more than the total of white cells, and why neutrophils and lymphocytes always belong side by side.

What do I do about a count that stays at the high end?

With an infection nothing; it falls with recovery. If the count stays against the upper bound without an infection, that is usually smoking, belly fat, poor sleep or chronic stress, and those keep your body in a light inflammatory state. Stopping smoking is the biggest step, and after that less belly fat and better sleep. Count on months before the count falls.

Which tests include neutrophils?

Neutrophils is in the Biological age test (€69, also as an add-on for €15), in the comprehensive test (€229) and in .

Related biomarkers

Sources

  1. 1.Unilabs, test catalogue (Dutch): white cell differential. 2026. bepalingenklapper.nl
  2. 2.Star-shl, test catalogue (Dutch): neutrophils. 2026. star-shl.nl
  3. 3.Certe, test catalogue (Dutch): neutrophil granulocytes. 2026. bepalingenwijzer.certe.nl
  4. 4.Clinical Diagnostics, lab guide (Dutch): neutrophils. 2026. clinicaldiagnostics.nl
  5. 5.LESA Laboratory diagnostics (Dutch primary-care laboratory agreement). 2026. richtlijnen.nhg.org

Educational information only, not medical advice. Consult a healthcare professional for clinical decisions.

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