Total IgE
Also known as: Immunoglobulin E, IgE
What Does Total IgE Measure?
Total IgE measures the overall level of Immunoglobulin E antibodies circulating in your blood. IgE is a type of protein produced by your immune system's B cells and plasma cells, and it plays a central role in allergic responses and defense against certain parasites. Unlike other antibody classes, IgE is present in very small quantities in the bloodstream under normal conditions, making it one of the least abundant immunoglobulins. The test reports results in international units per milliliter (IU/mL) or kilounits per liter (kU/L), and it captures the sum of all IgE antibodies regardless of what specific allergen they target.
Why Does Total IgE Matter?
Total IgE is a critical biomarker for evaluating allergic diseases, atopic conditions, and parasitic infections. Elevated levels are strongly associated with allergic disorders such as asthma, hay fever, atopic dermatitis (eczema), and food allergies, making it a valuable screening tool when these conditions are suspected. It also helps guide the decision to pursue more specific allergen testing and can be used to monitor the effectiveness of immunotherapy treatments over time. Beyond allergy, abnormally elevated IgE can signal underlying parasitic infections or rare immune disorders, while very low levels may point to certain immunodeficiency conditions. Understanding your total IgE in conjunction with your symptoms and other lab results helps clinicians develop targeted and effective treatment plans.
Normal Ranges
Males
< 100 IU/mL (adult males; many labs use < 87–100 IU/mL)
Females
< 100 IU/mL (adult females; many labs use < 87–100 IU/mL)
Children
Varies by age: newborns < 1.5 IU/mL; 1–5 years < 60 IU/mL; 6–9 years < 90 IU/mL; 10–15 years < 200 IU/mL
Causes of High Levels
- Allergic diseases (asthma, allergic rhinitis, hay fever, food allergies, atopic dermatitis/eczema)
- Parasitic infections (roundworm, hookworm, schistosomiasis, toxocariasis)
- Allergic bronchopulmonary aspergillosis (ABPA), a fungal-triggered lung condition
- Hyper-IgE syndrome (Job's syndrome), a rare primary immunodeficiency disorder
- Certain hematologic malignancies such as IgE-secreting multiple myeloma or Hodgkin's lymphoma
- Smoking and chronic exposure to environmental allergens or pollutants
Causes of Low Levels
- Primary immunodeficiency disorders such as common variable immunodeficiency (CVID)
- Selective IgE deficiency, a rare but recognized immune condition
- Agammaglobulinemia (Bruton's disease), a genetic condition causing very low or absent antibody production
How to Improve Your Total IgE
Diet
- Follow an anti-inflammatory diet rich in fruits, vegetables, whole grains, and omega-3 fatty acids to reduce overall immune hypersensitivity
- Identify and eliminate confirmed food allergens (e.g., peanuts, dairy, gluten if sensitized) under guidance of an allergist or dietitian
- Increase consumption of quercetin-rich foods such as apples, onions, and berries, which have natural antihistamine and mast-cell stabilizing properties
- Include probiotic-rich foods such as yogurt, kefir, and fermented vegetables to support gut microbiome balance and immune regulation
- Reduce ultra-processed foods, artificial additives, and high-sugar items that can promote inflammatory signaling
Supplements
- Vitamin D3: 1,000–4,000 IU/day — low vitamin D is associated with higher IgE levels and increased atopic disease risk
- Quercetin: 500–1,000 mg/day — acts as a natural mast cell stabilizer and may help modulate IgE-mediated responses
- Probiotics (Lactobacillus rhamnosus GG or mixed-strain): 5–10 billion CFU/day — evidence suggests benefit in reducing allergic sensitization
- Omega-3 fatty acids (fish oil): 1,000–3,000 mg EPA+DHA per day — may reduce allergic inflammation and IgE production
Related Biomarkers
Frequently Asked Questions
What does a high total IgE level mean?
A high total IgE level most commonly indicates that your immune system is producing excess IgE antibodies, which is typically seen in allergic conditions such as asthma, hay fever, eczema, and food allergies. However, elevated IgE can also result from parasitic infections, certain lung conditions like allergic bronchopulmonary aspergillosis (ABPA), rare immune disorders like Hyper-IgE syndrome, or even some blood cancers. A single elevated result should be interpreted alongside your symptoms, medical history, and additional testing rather than in isolation.
What is a normal total IgE level for adults?
For most adult men and women, a normal total IgE level is generally below 100 IU/mL, although some laboratories set their upper reference limit at 87 IU/mL or slightly higher. Levels above 150–200 IU/mL are often considered clearly elevated and warrant further investigation. It's important to note that reference ranges can vary between laboratories, so always interpret your result in the context of the specific lab's reference values printed on your report.
Can total IgE be used to diagnose a specific allergy?
Total IgE alone cannot identify a specific allergy. It is a broad screening test that tells you whether IgE antibodies are elevated overall, but it does not reveal which particular allergen is triggering the response. To pinpoint specific allergens, doctors order allergen-specific IgE tests (such as ImmunoCAP or RAST panels) that test your blood's reactivity to individual triggers like pollen, dust mites, peanuts, cat dander, or mold. Skin prick testing is another common method used alongside blood testing.