Lab result explainedInflammationLast updated November 8, 2026

ESR blood test: what a high or low erythrocyte sedimentation rate means

Erythrocyte sedimentation rate (ESR) (ESR) · Erythrocyte sedimentation rate (often ordered with CRP and a CBC) · reported in mm/hr (millimetres of settling per hour)

The erythrocyte sedimentation rate (ESR, or sed rate) measures how far red blood cells fall through a column of blood in one hour, in millimetres. When there is inflammation in the body, the liver makes more fibrinogen and other proteins that make red cells stick together and sink faster, so a higher ESR means more inflammation. A normal result is roughly under 15 mm/hr for men and under 20 mm/hr for women, but the upper limit rises steadily with age; a useful rule of thumb is age divided by 2 for men and (age plus 10) divided by 2 for women.

ESR is one of the oldest blood tests still in routine use. It is not specific: infection, autoimmune disease, cancer, anemia, kidney disease, pregnancy and simply getting older all raise it. It is most useful for diagnosing and monitoring a handful of conditions where it is particularly high and informative, especially polymyalgia rheumatica, giant cell (temporal) arteritis, rheumatoid arthritis, multiple myeloma and bone or joint infections, and as a general check when someone is unwell without an obvious cause.

Most laboratories now also run C-reactive protein (CRP), which rises and falls within days rather than weeks and is less affected by anemia and age. The two are often read together: a high CRP with a high ESR confirms active inflammation; a high ESR with a normal CRP points toward lupus, myeloma, anemia or a chronic low-grade process; and a very high ESR (over 100 mm/hr) almost always has a serious, identifiable cause.

ESR at a glance

  • What it is: how many millimetres red cells settle in one hour in a standard tube (Westergren method); a slow, indirect measure of inflammation.
  • Normal: men under about 15 mm/hr, women under about 20 mm/hr; upper limit by age is roughly age/2 for men and (age+10)/2 for women. Labs differ.
  • Mildly high (20–50 mm/hr): common and non-specific; infection, anemia, pregnancy, obesity, kidney disease, age or a chronic inflammatory condition.
  • Very high (over 100 mm/hr): usually a serious infection, giant cell arteritis or polymyalgia rheumatica, multiple myeloma, metastatic cancer or active vasculitis; needs a full work-up.
  • Low ESR (0–2 mm/hr) is normal; it is only notable with polycythemia, sickle cell disease or very abnormal proteins.
  • ESR vs CRP: CRP changes within hours to days and is more specific; ESR lags by days to weeks and stays up longer, and is raised more by anemia and age.

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What ESR measures

Red blood cells carry a negative surface charge that keeps them apart. Fibrinogen, immunoglobulins and other large, positively charged plasma proteins neutralise that charge and let red cells stack into columns called rouleaux, which, being heavier, fall faster through plasma. The laboratory draws blood into a tube with anticoagulant, stands it vertically, and reads how many millimetres of clear plasma have appeared at the top after exactly one hour. The Westergren method is the international reference; automated analysers now reproduce it in a few minutes with results calibrated to Westergren values.

Because the test depends on both the proteins in plasma and the red cells themselves, anything that changes red cells changes ESR independently of inflammation. Anemia raises it (fewer cells fall faster), polycythemia lowers it, and abnormally shaped cells such as sickle cells or spherocytes cannot form rouleaux and lower it. High fibrinogen from pregnancy, oral contraceptives, diabetes or kidney disease raises it, as do paraproteins in myeloma and the high immunoglobulin levels of lupus or chronic infection.

ESR responds slowly. It starts to rise 24 to 48 hours after inflammation begins, often peaks a week or more later, and can take weeks to return to normal after an illness because fibrinogen and immunoglobulins clear slowly. CRP, by contrast, rises within 6 hours and halves roughly every day once the trigger stops. That lag makes ESR a poor test for acute change but a reasonable indicator of inflammation over the preceding weeks, which is why it remains part of disease-activity scores in rheumatoid arthritis and the diagnostic criteria for polymyalgia rheumatica and giant cell arteritis.

Normal range for ESR

Reference ranges vary between labs and by age, sex and pregnancy. Use the range printed on your own report.

GroupTypical range (mm/hr (millimetres of settling per hour))Notes
Men under 500–15 mm/hrSome labs quote 0–10 or 0–20. Use the printed range.
Women under 500–20 mm/hrWomen run slightly higher at every age, partly because of lower hematocrit.
Men 50 and over0–20 mm/hrAge-adjusted upper limit: age divided by 2 (a 70-year-old man: 35 mm/hr).
Women 50 and over0–30 mm/hrAge-adjusted upper limit: (age plus 10) divided by 2 (a 70-year-old woman: 40 mm/hr).
Children0–10 mm/hrNewborns are lower (0–2 mm/hr); teenagers approach adult values.
PregnancyUp to 40–70 mm/hr in the third trimesterRising fibrinogen and dilutional anemia; ESR is not a reliable inflammation marker in pregnancy or for 6 weeks after delivery.
Mild to moderate elevation20–50 mm/hr (above the age-adjusted limit)Non-specific. Infection, anemia, obesity, chronic kidney disease, chronic inflammatory disease, or no cause found on follow-up in about a third.
Marked elevation50–100 mm/hrActive rheumatoid arthritis, polymyalgia rheumatica, inflammatory bowel disease, serious infection, cancer, nephrotic syndrome.
Extreme elevationAbove 100 mm/hrIn published series over 90 percent have a serious cause: infection (about a third, including osteomyelitis, endocarditis, abscess, tuberculosis), cancer or myeloma (about a quarter), giant cell arteritis, lupus, vasculitis or advanced kidney disease.

High ESR

A high ESR means there is probably more fibrinogen or immunoglobulin in your plasma than usual, which almost always reflects inflammation, infection, tissue damage, or an abnormal protein, and sometimes simply anemia or age. The size of the rise matters. Values between the upper limit and about 50 mm/hr are common, often transient, and frequently have a benign explanation (a recent infection, iron-deficiency anemia, pregnancy, obesity, kidney disease, or just being over 70). Repeating the test in a few weeks, alongside a CRP, resolves a large share of these.

Values from 50 to 100 mm/hr usually mean active disease that can be found: rheumatoid arthritis or another inflammatory arthritis, polymyalgia rheumatica, inflammatory bowel disease, a chronic or deep-seated infection, lupus, a blood protein disorder, or cancer. Above 100 mm/hr, studies consistently show that nine in ten people have a serious identifiable cause, with infection, cancer (particularly multiple myeloma and metastatic disease) and giant cell arteritis or other vasculitis leading the list. A very high ESR should never be put down to age alone.

ESR is interpreted alongside CRP. If both are high, inflammation is active now. If ESR is high but CRP is normal, the process is either resolving (CRP falls first), chronic and low-grade, or one of the conditions that raise ESR without much CRP: systemic lupus, multiple myeloma and other paraproteinemias, anemia, pregnancy, and kidney disease. In older adults with a new headache, jaw pain on chewing or visual disturbance, an ESR over 50 is treated as giant cell arteritis until proven otherwise because untreated it can cause permanent blindness within days.

Common causes

  1. Infection, especially chronic or deep-seated

    Bone infection (osteomyelitis), infected joints or prosthetic joints, endocarditis, abscesses, tuberculosis and pelvic infections produce ESRs of 50 to over 100 mm/hr. Acute viral and minor bacterial infections raise it more modestly and the rise persists for 2 to 4 weeks after recovery.

  2. Rheumatoid arthritis and other inflammatory arthritis

    ESR tracks disease activity and is built into the DAS28 score used to guide treatment. Active rheumatoid arthritis typically runs 30 to 80 mm/hr; psoriatic arthritis and ankylosing spondylitis raise it less reliably.

  3. Polymyalgia rheumatica and giant cell arteritis

    Classic causes of an ESR above 50 mm/hr, often 80 to 120, in people over 50 with shoulder and hip girdle stiffness (PMR) or new headache, scalp tenderness, jaw claudication or vision loss (GCA). About 5 to 20 percent of GCA cases have a normal ESR, so CRP and clinical judgement are also used.

  4. Anemia

    Fewer red cells settle faster, so a hemoglobin of 9 to 10 g/dL alone can push ESR to 30 to 50 mm/hr without any inflammation. Iron-deficiency anemia is one of the commonest explanations for a mildly raised ESR in otherwise well women.

  5. Multiple myeloma and other paraproteinemias

    Monoclonal immunoglobulins cause intense rouleaux formation; ESR over 100 mm/hr with a normal CRP, anemia, bone pain, high calcium or kidney impairment should prompt serum protein electrophoresis and free light chains. Waldenstrom macroglobulinemia and MGUS also raise it.

  6. Cancer

    Lymphoma, metastatic breast, lung, colon and kidney cancers raise ESR through inflammatory cytokines and tissue breakdown. ESR is not a screening test, but a persistently high value with weight loss, night sweats or a lump needs investigation.

  7. Autoimmune and connective tissue disease

    Systemic lupus erythematosus characteristically raises ESR while CRP stays low; the ESR reflects high immunoglobulins rather than acute inflammation. Vasculitis, Sjogren's syndrome, scleroderma, inflammatory myositis and sarcoidosis also raise it.

  8. Kidney disease and nephrotic syndrome

    Chronic kidney disease raises fibrinogen and often causes anemia; in end-stage disease ESR is commonly 50 to 100 mm/hr with no infection. Nephrotic syndrome loses albumin and raises fibrinogen, producing very high values.

  9. Pregnancy, oral estrogen and obesity

    Fibrinogen rises through pregnancy, pushing ESR to 40 to 70 mm/hr by the third trimester, and stays raised for several weeks post-partum. The combined pill and oral HRT raise it modestly, and obesity adds a few mm/hr through low-grade inflammation and higher fibrinogen.

  10. Older age and medications

    ESR drifts up with age even in healthy people, hence the age-adjusted limits. Dextran infusions, methyldopa, theophylline, vitamin A and some anticonvulsants are reported to raise it; high cholesterol raises it slightly through altered red cell membranes.

Symptoms that can go with it

  • Often none when the ESR is only mildly raised; the test is frequently ordered because of vague fatigue
  • Fever, night sweats and unexplained weight loss, which raise concern for infection, cancer or myeloma
  • Morning stiffness lasting over 45 minutes in the shoulders, neck and hips in someone over 50 (polymyalgia rheumatica)
  • New headache, scalp tenderness, jaw pain when chewing or any visual change in someone over 50 (giant cell arteritis, an emergency)
  • Painful, swollen or warm joints, especially small joints of the hands and feet (inflammatory arthritis)
  • Bone pain, particularly in the back or ribs, with tiredness, frequent infections or thirst (possible myeloma)
  • Abdominal pain, bloody diarrhea or mouth ulcers (inflammatory bowel disease)
  • Localised bone or back pain with fever, or pain over a joint replacement (deep infection)

Low ESR

An ESR of 0, 1 or 2 mm/hr is normal and is the usual result in healthy children and young men. There is no lower limit of concern, and a low ESR is reassuring when inflammation was the question, though it does not exclude every inflammatory disease: a minority of people with giant cell arteritis, early infection or localised inflammation have a normal ESR, and CRP or imaging may still be needed if symptoms are convincing.

A few conditions actively push ESR down by changing the red cells or plasma. Polycythemia (too many red cells) crowds the cells and slows settling; sickle cell disease, hereditary spherocytosis and other red cell shape abnormalities prevent rouleaux forming; very high white cell counts in leukemia can do the same; and low fibrinogen from severe liver disease, disseminated intravascular coagulation or inherited afibrinogenemia removes the protein that normally drives settling. In these settings a 'normal' ESR can mask real inflammation, and CRP is the better marker.

Common causes

  1. Normal health

    Most healthy people under 40, particularly men, have an ESR under 10 mm/hr; a result of 0 to 2 is common and needs no explanation.

  2. Polycythemia

    A high hematocrit (over 50 to 55 percent), whether from polycythemia vera, smoking, sleep apnea or living at altitude, slows red cell settling and can keep ESR near zero even during infection.

  3. Sickle cell disease and other red cell shape disorders

    Sickled cells, spherocytes and the cells of some thalassemias cannot stack into rouleaux, so ESR stays low; CRP is used instead to detect infection or a crisis in people with sickle cell disease.

  4. Low fibrinogen

    Severe liver failure, disseminated intravascular coagulation and rare inherited fibrinogen deficiencies remove the main protein that drives settling; ESR can be near zero despite serious illness.

  5. Very high white cell count or heart failure

    Leukemia with a very high white count and severe congestive heart failure (through increased plasma viscosity and other mechanisms) are reported to lower ESR.

  6. High-dose corticosteroids and NSAIDs

    Prednisone and other anti-inflammatories lower ESR by suppressing the inflammation that raises it; aspirin and NSAIDs have a small additional direct effect.

Symptoms that can go with it

  • None; a low ESR causes no symptoms
  • If a condition that lowers ESR is present (sickle cell disease, polycythemia), its own symptoms dominate and CRP is used to track inflammation

Read it alongside

  • CRP (C-reactive protein) — faster and more specific; both high confirms active inflammation, high ESR with normal CRP points to lupus, myeloma, anemia, pregnancy or kidney disease.
  • Hemoglobin and hematocrit — anemia alone raises ESR and polycythemia lowers it; always check before interpreting a borderline result.
  • White blood cell count and differential — a raised neutrophil count with a high ESR favours bacterial infection; abnormal cells raise concern for a blood cancer.
  • Serum protein electrophoresis and free light chains — the key tests when ESR is over 100 mm/hr with a normal CRP, to find a paraprotein.
  • Creatinine and eGFR — chronic kidney disease is a common, often overlooked reason for a persistently raised ESR.
  • Rheumatoid factor, anti-CCP and ANA — ordered when joint pain or systemic symptoms accompany a high ESR.
  • Ferritin — iron-deficiency anemia raises ESR; ferritin also rises as an acute-phase protein with active inflammation.
  • Urinalysis and blood cultures — when infection is possible and the source is not obvious.

What usually happens next

  1. A mildly raised ESR (under 50 mm/hr) in someone who feels well is usually repeated in 4 to 6 weeks together with a CRP and CBC; roughly a third normalise, and a persisting rise prompts a fuller history, examination and targeted tests.
  2. If anemia is present, it is investigated and corrected first, since it may explain the whole ESR rise.
  3. An ESR above 50 mm/hr, or any raised ESR with fever, weight loss, night sweats, bone pain or new joint symptoms, leads to a structured work-up: CRP, CBC, kidney and liver tests, protein electrophoresis, urinalysis, autoimmune screen and often a chest X-ray.
  4. An ESR above 100 mm/hr is not watched; expect imaging and blood tests aimed at infection, myeloma or cancer, and vasculitis, usually within days.
  5. If you are over 50 with a high ESR and any headache, scalp tenderness, jaw pain or visual symptom, say so immediately; giant cell arteritis is treated the same day, before biopsy results.
  6. In a known inflammatory disease, ESR is one measure of control; ask how it fits with your symptoms, CRP and examination rather than aiming for a number on its own.

Diet, lifestyle and natural levers with evidence

What can move ESR once the cause is known. Nothing here replaces finding the cause.

Correct iron-deficiency anemia

Strong evidence

Anemia itself raises ESR, independent of inflammation. Restoring hemoglobin from 10 to 13 g/dL typically brings a 'mildly raised' ESR of 30 to 40 mm/hr back into the normal range within 2 to 3 months. Iron tablets or infusions correct iron-deficiency anemia in most people within 8 to 12 weeks; the cause of the deficiency (menstrual loss, gut blood loss, poor absorption) still needs to be found.

Do not take iron without a confirmed low ferritin; iron overload is harmful and iron can mask gut bleeding. Separate iron from levothyroxine and some antibiotics by 4 hours.

Weight loss when carrying excess abdominal fat

Moderate evidence

Visceral fat raises fibrinogen and interleukin-6, both of which raise ESR. Weight-loss interventions lower fibrinogen by about 0.2 to 0.3 g/L and CRP by around 0.13 mg/L per kilogram lost in meta-analyses, and ESR falls alongside, though it is less often reported. The effect is modest for ESR (a few mm/hr) but moves people near the age-adjusted limit back inside it.

Regular moderate exercise

Moderate evidence

Exercise training trials lower CRP by about 0.3 to 0.5 mg/L and fibrinogen by a small amount, and observational studies find lower ESR in physically active older adults. In rheumatoid arthritis, supervised aerobic and resistance programmes improve function without raising ESR or disease activity, and some trials show small ESR reductions. 150 minutes a week of moderate activity is the dose most trials used.

A single very hard or unaccustomed session raises inflammatory markers for 2 to 3 days; do not test straight after a race or a new programme.

Mediterranean-style eating pattern

Moderate evidence

In a randomised trial in rheumatoid arthritis, 12 weeks of a Mediterranean diet reduced disease activity (DAS28) and improved function compared with a control diet, with a fall in CRP; the PREDIMED trial found lower CRP, IL-6 and fibrinogen with a Mediterranean diet over one to five years. ESR is rarely the primary endpoint, but it tracks these markers. Higher fibre intake (over 25 g a day) is associated with lower inflammatory markers in cohort studies.

Omega-3 fatty acids (fish oil)

Moderate evidence

Meta-analyses of randomised trials in rheumatoid arthritis found that 2.7 g or more a day of EPA plus DHA for at least 3 months reduced tender joint counts, morning stiffness and NSAID use, with small reductions in ESR (around 3 to 5 mm/hr in pooled analyses) and CRP. Effects in healthy people with a normal ESR are negligible.

Doses above 3 g a day can increase bleeding tendency and, in some trials, atrial fibrillation; discuss if you take anticoagulants or antiplatelet drugs.

Curcumin

Preliminary evidence

Small randomised trials in rheumatoid arthritis and ulcerative colitis report that 500 to 1,500 mg a day of an enhanced-absorption curcumin for 8 to 12 weeks lowers disease activity scores and CRP, with ESR reductions of roughly 5 to 10 mm/hr in some trials. The trials are small, short and heterogeneous, so this is supporting evidence rather than a reason to change treatment.

Can increase bleeding with anticoagulants, interact with some chemotherapy and cause gallbladder contraction; rare reports of liver injury with high-dose supplements.

When to see a clinician promptly

  • An ESR above 50 mm/hr in anyone over 50 with new headache, scalp tenderness, jaw pain on chewing, double vision or any loss of vision: possible giant cell arteritis, which can cause permanent blindness and is treated the same day.
  • An ESR above 100 mm/hr: nine in ten people have a serious cause (deep infection, myeloma or cancer, vasculitis) and prompt investigation is needed.
  • A raised ESR with fever, shaking chills, severe localised bone, back or joint pain, or pain and swelling over a joint replacement: possible osteomyelitis, septic arthritis, endocarditis or abscess.
  • A raised ESR with unexplained weight loss, drenching night sweats, bone pain, a new lump or persistent fatigue.
  • A raised ESR with new, persistent joint pain and morning stiffness lasting over 30 to 45 minutes, or with shoulder and hip girdle stiffness in later life.
  • Any ESR that stays above the age-adjusted limit on a repeat test 4 to 6 weeks later with no explanation.

Frequently asked questions

What is a normal ESR by age?

A widely used rule is that the upper limit of normal is age divided by 2 for men and (age plus 10) divided by 2 for women. So a 30-year-old man should be under 15 mm/hr, a 30-year-old woman under 20, a 60-year-old man under 30 and a 60-year-old woman under 35. Many labs print a single range (often 0 to 15 or 0 to 20 mm/hr) that does not adjust for age, so a result of 25 in a healthy 70-year-old may be flagged high but still be within the expected range for age.

Is an ESR of 30, 40 or 60 high?

An ESR of 30 mm/hr is above the standard adult range but within the age-adjusted range for a woman over 50 or a man over 60, and is commonly explained by anemia, a recent infection, pregnancy or obesity. An ESR of 40 is mildly to moderately raised for most adults and is usually repeated with a CRP and CBC. An ESR of 60 is clearly raised at any age and generally prompts a search for inflammatory disease, infection, kidney disease or a blood protein disorder, especially if symptoms are present.

What is the difference between ESR and CRP?

Both rise with inflammation, but CRP is a single protein made by the liver that rises within 6 hours and falls within days, while ESR is a physical property of the blood that depends on fibrinogen, immunoglobulins and the red cells themselves and takes days to weeks to rise and fall. CRP is more specific for acute inflammation and infection and is not affected by anemia or age. ESR is better for a few chronic conditions (polymyalgia rheumatica, giant cell arteritis, lupus, myeloma) and shows the inflammatory burden over the previous few weeks. Most clinicians order both when the cause of symptoms is unclear.

What does it mean if ESR is high but CRP is normal?

The combination suggests either inflammation that is resolving (CRP falls first), or a condition that raises ESR without triggering much CRP: systemic lupus, multiple myeloma or another paraprotein, anemia, pregnancy, chronic kidney disease, or simply older age. If ESR is above 100 mm/hr with a normal CRP, protein electrophoresis to look for myeloma is one of the first tests ordered.

What ESR level indicates cancer?

There is no ESR that diagnoses cancer, and most high ESRs are not cancer. In series of people with an ESR above 100 mm/hr, about a quarter had a malignancy, most often multiple myeloma, lymphoma or metastatic solid cancer, and nearly all of those had other findings such as anemia, weight loss, bone pain or abnormal proteins. A mildly raised ESR in someone who feels well is far more likely to be anemia, infection or inflammation than cancer.

Can stress, anxiety or lack of sleep raise ESR?

Only slightly. Chronic stress, depression and poor sleep are associated with modestly higher inflammatory markers in population studies, enough to add a few mm/hr but not to produce values of 40, 60 or 100. A clearly raised ESR should never be attributed to stress without excluding infection, anemia, inflammatory disease and kidney disease.

How can I lower my ESR naturally?

ESR falls when the cause is treated, so the first step is finding the cause. Beyond that, the measures with evidence are correcting iron-deficiency anemia, losing excess abdominal fat, regular moderate exercise, a Mediterranean-style diet, and in inflammatory arthritis, fish oil at 2.7 g or more of EPA plus DHA a day. Each produces modest changes of a few mm/hr; none substitutes for treating an infection, inflammatory disease or blood disorder.

Does ESR go up with age?

Yes. Fibrinogen and immunoglobulin levels rise slowly throughout adult life and hemoglobin drifts down, so a healthy 75-year-old commonly has an ESR of 20 to 35 mm/hr. This is why age-adjusted limits exist. Age does not, however, explain values over about 40 to 50 mm/hr, and in older adults a high ESR is more likely, not less, to have a significant cause such as polymyalgia rheumatica, giant cell arteritis, myeloma or infection.

References

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  2. Sed rate (erythrocyte sedimentation rate). Mayo Clinic (2023)View source
  3. Inflammation markers (C-reactive protein, erythrocyte sedimentation rate). Merck Manual Professional Version (2024)
  4. Brigden ML. Erythrocyte sedimentation rate and C-reactive protein measurements and their relevance in clinical medicine. Wisconsin Medical Journal (2016)
  5. Brigden ML. Clinical utility of the erythrocyte sedimentation rate. American Family Physician (1999)
  6. Bray C, Bell LN, Liang H, et al.. Approach to the patient with an elevated erythrocyte sedimentation rate. Wisconsin Medical Journal (2016)
  7. Miller A, Green M, Robinson D. Determination of the normal range of the erythrocyte sedimentation rate in the elderly. British Medical Journal (1983)
  8. Fincher RM, Page MI. Extreme elevation of the erythrocyte sedimentation rate: a retrospective study of 100 patients. Archives of Internal Medicine (1986)
  9. Dasgupta B, Cimmino MA, Maradit-Kremers H, et al.. 2012 provisional classification criteria for polymyalgia rheumatica: a European League Against Rheumatism/American College of Rheumatology collaborative initiative. Annals of the Rheumatic Diseases (2012)
  10. Kratz A, Plebani M, Peng M, Lee YK, McCafferty R, Machin SJ. ICSH recommendations for modified and alternate methods measuring the erythrocyte sedimentation rate. International Journal of Laboratory Hematology (2017)
  11. Lee YH, Bae SC, Song GG. Efficacy of omega-3 polyunsaturated fatty acids in the treatment of rheumatoid arthritis: a systematic review and meta-analysis. Archives of Medical Research (2012)
  12. Skoldstam L, Hagfors L, Johansson G. An experimental study of a Mediterranean diet intervention for patients with rheumatoid arthritis. Annals of the Rheumatic Diseases (2003)

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This page is educational and is not medical advice or a diagnosis. Lab results have to be interpreted together with your history, symptoms and other results by a clinician who knows you. Do not start or stop a supplement to change a lab value before the cause is known.