Loss of Smell (Anosmia): Nasal Polyps and Allergic Inflammation
Published: Tue Mar 24 2026 00:00:00 GMT+0000 (Coordinated Universal Time)
Losing your sense of smell — known medically as anosmia — can be a deeply unsettling experience. It may affect how you taste food, detect hazards like gas leaks, and engage with everyday life. For some individuals, chronic nasal inflammation may also contribute to difficulty concentrating or brain fog. For many people in the UK, loss of smell is closely linked to nasal polyps and underlying allergic inflammation, conditions that can develop gradually and sometimes go unrecognised for months or even years. Understanding the relationship between these conditions and the blood markers that may indicate allergic or inflammatory activity can be an important first step towards seeking appropriate healthcare advice.
This educational guide explores how nasal polyps and allergic inflammation may contribute to anosmia, which biomarkers can offer useful insights, and how proactive health screening may help you better understand what is happening within your body.
What Is Anosmia? A Quick Definition
Anosmia is the partial or complete loss of the sense of smell. It can result from nasal obstruction, nerve damage, or inflammatory processes affecting the nasal passages and olfactory region. When caused by nasal polyps or allergic inflammation, anosmia may develop gradually and can sometimes be associated with elevated inflammatory or allergic biomarkers identifiable through blood testing.
How Nasal Polyps and Allergic Inflammation Affect Your Sense of Smell
Nasal polyps are soft, painless, non-cancerous growths that develop on the lining of the nasal passages or sinuses. They are frequently associated with chronic inflammation, and when they grow large enough, they can physically obstruct the airflow reaching the olfactory receptors at the top of the nasal cavity.
Allergic inflammation — a persistent immune response to environmental allergens such as dust mites, pollen, pet dander, or mould — can cause ongoing swelling of the nasal mucosa. Over time, this chronic swelling may contribute to polyp formation and progressive loss of smell.
Key factors that may connect these conditions include:
- Eosinophilic inflammation — a type of immune cell activity commonly elevated in allergic conditions and nasal polyposis
- IgE-mediated responses — the antibody pathway most commonly associated with allergic reactions
- Chronic rhinosinusitis — long-term inflammation of the sinuses, often coexisting with nasal polyps
- Aspirin-exacerbated respiratory disease (AERD) — a triad of asthma, nasal polyps, and aspirin sensitivity
Practical Insight: If you have noticed a gradual decline in your ability to smell everyday scents — such as coffee, cooking, or perfume — this may sometimes be associated with underlying nasal or allergic inflammation worth investigating further.
Which Blood Markers May Be Relevant?
Blood testing cannot diagnose nasal polyps or anosmia directly. However, certain biomarkers can provide useful context about whether allergic or inflammatory processes may be active in the body. These results, when shared with an appropriate healthcare professional, may support a broader clinical picture.
Key Biomarkers to Consider
| Biomarker | What It May Indicate | Relevance to Anosmia |
|---|---|---|
| Total IgE | Overall allergic antibody level | Elevated levels can suggest an allergic predisposition that may contribute to nasal inflammation |
| Specific IgE (allergen panels) | Sensitivity to individual allergens | May help identify environmental triggers linked to chronic nasal symptoms |
| Eosinophil count (FBC) | A type of white blood cell involved in allergic responses | Raised eosinophils can sometimes be associated with eosinophilic nasal polyposis |
| CRP (C-Reactive Protein) | General inflammation marker | May indicate systemic inflammatory activity, though it is non-specific |
| ESR (Erythrocyte Sedimentation Rate) | Another general inflammation indicator | Can suggest ongoing chronic inflammation when elevated |
| Vitamin D | Immune regulation | Low vitamin D levels have been observed in some studies alongside chronic rhinosinusitis and nasal polyps |
Please note: Total IgE and specific IgE allergen panels are available through private allergy screening clinics such as ours. Eosinophil count (FBC), CRP, ESR, and vitamin D are general blood markers typically requested through your GP or NHS services. Understanding both sets of results together can provide a more complete picture.
Practical Insight: A single raised marker does not confirm a specific condition. However, a pattern of elevated allergic and inflammatory markers may sometimes highlight the value of seeking further clinical evaluation.
Who Should Consider Allergy and Inflammation Screening?
Not everyone who experiences a temporary change in smell needs blood testing. However, screening may be worth considering if you:
- Have experienced a gradual or persistent loss of smell lasting several weeks or longer
- Have a known history of allergies, hay fever, eczema, or asthma — understanding whether your rhinitis is allergic or non-allergic may provide additional clarity
- Experience recurring nasal congestion or sinus pressure without clear cause
- Have been told you may have nasal polyps and wish to understand your inflammatory profile
- Want to check whether allergic sensitisation to common environmental allergens may be present
- Have a family history of allergic conditions or chronic sinusitis
For individuals living and working in London, exposure to urban air pollutants and high pollen counts during spring and summer months may further contribute to ongoing nasal inflammation. Proactive screening can offer a clearer picture of your body's current immune and inflammatory status.
If you are interested in understanding your allergic profile, our allergy blood testing services may provide a helpful starting point.
How Often Should You Screen for Allergic Inflammation?
The appropriate frequency of testing can vary depending on individual circumstances. As a general educational guide:
| Situation | Suggested Consideration |
|---|---|
| No symptoms, general curiosity | Once as a baseline may be sufficient |
| Mild seasonal allergies | Annually, particularly before peak allergy seasons |
| Chronic nasal congestion or reduced smell | Consider testing and then discuss results with a healthcare professional |
| Known nasal polyps or chronic rhinosinusitis | Periodic monitoring of eosinophils and IgE may be useful, guided by medical advice |
| Post-viral anosmia (e.g., after COVID-19) | Screening may help distinguish allergic causes from other contributing factors |
Practical Insight: If you have already undergone testing and your results were within normal ranges, repeat screening may only be necessary if your symptoms change or new concerns arise.
What Do Your Results Mean?
Blood test results from a screening clinic provide data — not a diagnosis. Understanding what your numbers may suggest is an important part of being proactive about your wellbeing.
- Elevated Total IgE — can suggest the immune system is producing higher-than-typical levels of allergic antibodies. This may sometimes be seen in individuals with allergic rhinitis, asthma, or nasal polyposis.
- Positive Specific IgE results — may indicate sensitisation to particular allergens. Sensitisation does not always mean clinical allergy, but it can provide useful information when considered alongside symptoms.
- Raised eosinophils (available via full blood count through your GP) — can sometimes highlight eosinophilic inflammation, which is commonly associated with nasal polyps and allergic conditions.
- Low Vitamin D (available through your GP or NHS services) — may be relevant as some research has explored associations between vitamin D insufficiency and chronic upper airway inflammation, though evidence is still developing.
It is important to have your results reviewed by an appropriate healthcare professional who can interpret them in the context of your full medical history and symptoms.
For further reading on how allergy testing works, you may find our blog hub helpful.
NHS vs Private Screening: A Balanced Comparison
In the UK, both NHS and private pathways offer routes to investigating loss of smell and related allergic conditions. Understanding the differences can help you make an informed choice.
| Factor | NHS Pathway | Private Screening |
|---|---|---|
| Access | Via GP referral; may involve waiting times | Direct access without referral |
| Waiting times | Can vary; specialist ENT referrals may take weeks to months | Typically faster appointment availability |
| Scope of testing | Guided by clinical presentation and GP assessment | You may select specific allergy or inflammation panels |
| Cost | Free at point of use | Fee applies; check the clinic website for current information |
| Follow-up | Integrated NHS care pathway | Results provided for you to share with your healthcare provider |
Both routes have clear merits. Private screening can sometimes complement the NHS pathway by providing timely baseline data, particularly for individuals in London who may face longer referral wait times for specialist services.
Practical Insight: Private screening is not a replacement for NHS care. It can, however, support informed conversations with your GP or specialist by providing objective blood marker data.
The London Context: Urban Allergies and Nasal Health
Living in London presents unique considerations for nasal and allergic health. High levels of traffic-related air pollution, particularly nitrogen dioxide and particulate matter, have been associated in research with increased nasal inflammation and may exacerbate symptoms in individuals predisposed to allergic conditions.
Additionally, London's diverse built environment — from older properties with potential mould exposure to densely planted parks releasing seasonal pollen — means that allergen exposure can be varied and sometimes unexpected.
Accessing allergy screening in London can be a practical step for residents who wish to better understand their individual allergen sensitivities and inflammatory markers.
Frequently Asked Questions
Can blood testing diagnose nasal polyps?
Blood testing alone cannot diagnose nasal polyps. However, certain markers such as eosinophil counts and total IgE levels may sometimes be elevated in individuals with nasal polyposis, providing supportive context. A definitive assessment of nasal polyps typically requires clinical examination by an appropriate healthcare professional, often including nasal endoscopy.
What is the most common cause of loss of smell in the UK?
In the UK, common causes of loss of smell include upper respiratory infections, chronic rhinosinusitis with or without nasal polyps, and allergic rhinitis. Understanding whether your symptoms point to sinusitis or hay fever can help guide appropriate investigation. Post-viral anosmia, including cases following COVID-19, has also become widely recognised. Blood markers associated with allergic inflammation may help clarify whether an allergic component could be contributing to symptoms.
How does allergic inflammation lead to anosmia?
Allergic inflammation can cause persistent swelling of the nasal mucosa, reducing airflow to the olfactory receptors located at the top of the nasal cavity. Over time, chronic inflammation may also contribute to the development of nasal polyps, which can further obstruct smell perception. Elevated eosinophils and IgE levels may sometimes indicate this type of inflammatory activity.
Is loss of smell always permanent?
Loss of smell is not always permanent. In many cases, particularly where allergic inflammation or nasal polyps are involved, appropriate management guided by a healthcare professional may help improve olfactory function. Early investigation of underlying causes can sometimes support better long-term outcomes, though individual experiences vary.
Should I see my GP if I lose my sense of smell?
If you experience a persistent or unexplained loss of smell, it is advisable to seek medical advice from your GP. They can assess your symptoms, consider potential causes, and refer you to specialist services if appropriate. Having recent blood test results available may support this conversation with objective data.
What allergens are most commonly linked to nasal polyps?
Nasal polyps are frequently associated with sensitivity to airborne allergens such as house dust mites, mould spores, pet dander, and certain pollens. Specific IgE testing for these allergens may help identify potential sensitivities, though sensitisation does not always equate to clinical allergy.
Can children develop anosmia from allergic inflammation?
While less common than in adults, children with significant allergic rhinitis or chronic rhinosinusitis may experience reduced smell perception. If a child reports difficulty smelling, it is important to seek appropriate medical advice. Allergy screening may sometimes be considered as part of a broader clinical assessment.
How long does it take to get allergy blood test results?
Turnaround times can vary depending on the clinic and the specific tests requested. For information about testing timelines and available panels, visiting the Allergy Clinic website can provide current details relevant to your needs.
Is there a link between asthma and loss of smell?
Research suggests a notable association between asthma, particularly eosinophilic asthma, and nasal polyps with associated anosmia. Individuals with asthma who also experience nasal congestion and reduced smell may benefit from understanding their eosinophil and IgE levels through blood screening.
Can air pollution in London worsen anosmia?
Emerging research suggests that chronic exposure to urban air pollutants may contribute to nasal mucosal inflammation, potentially exacerbating symptoms in individuals already prone to allergic rhinitis or nasal polyposis. While blood testing cannot measure pollution exposure directly, monitoring inflammatory markers may offer indirect insights.
Supporting Your Wellbeing Through Knowledge
Understanding the potential connection between loss of smell, nasal polyps, and allergic inflammation is an empowering step. Blood screening for allergic and inflammatory markers does not provide a diagnosis, but it can offer meaningful data to support informed conversations with your healthcare provider.
At The Allergy Clinic, we provide allergy blood testing services designed to help you gain a clearer picture of your body's immune and inflammatory activity. Your results are delivered directly to you, ready to share with your GP or specialist. Whether you are exploring concerns about reduced smell, persistent nasal congestion, or known allergic conditions, proactive screening may help you take the next step with confidence.
If you would like to explore your options, we welcome you to visit our website or get in touch at a time that suits you. There is no pressure — only the opportunity to learn more about your own health.
About This Article
This article has been produced in accordance with UK medical editorial best practice. The content is evidence-based, drawing upon published clinical literature and established allergy and immunology science. It has been written to support general understanding and does not constitute clinical advice.
All content has been prepared in accordance with GMC advertising guidance, CQC patient communication standards, and ASA compliance requirements.
Medical Disclaimer
This article has been produced for educational and informational purposes only. It does not constitute medical advice, diagnosis, or treatment. The content is intended to support general understanding of topics related to allergy, inflammation, and loss of smell, and should not be used as a substitute for professional medical guidance.
Individual symptoms, health concerns, or blood test results should always be assessed and interpreted by an appropriately qualified healthcare professional. No guarantees regarding health outcomes are made or implied within this article.
The Allergy Clinic provides testing services only. Results are delivered directly to you, ready to share with your GP or specialist. We do not provide diagnosis, treatment, prescriptions, clinical reports, or specialist medical opinions.
This content has been prepared in accordance with UK medical editorial best practice, GMC advertising guidance, CQC patient communication standards, and ASA standards.
Written Date: 24 March 2026 Next Review Date: 24 March 2027