Mould Exposure — The Hidden Health Effects on the Body

By Dr (TCM) Attilio D'Alberto | Traditional Chinese Medicine Practitioner, Wokingham, Berkshire

Mould and the mycotoxins it produces are one of the most underestimated environmental drivers of chronic ill health in the UK. Patients with brain fog, chronic fatigue, sinusitis, unexplained skin rashes, autoimmune flare patterns and chemical sensitivity often turn out to be living or working in a mould-affected building — sometimes for years before the connection is made. In traditional Chinese medicine (TCM) mould is described precisely — as an external Damp pathogen with a particular affinity for the Lung and Spleen — and the framework explains both why exposure produces such varied symptoms and why recovery takes time.

On this page

1. Why mould exposure is so common in the UK
2. What is mould and what are mycotoxins?
3. Respiratory effects — the Lung takes the first hit
4. Immune and neurological effects (CIRS)
5. The Chinese medicine view — external Damp invading the body
6. Chronic exposure — how Damp becomes Phlegm and Spleen weakness
7. Symptoms to watch for — a checklist
8. Who is most affected
9. How to detect mould in your home
10. How to remove mould from your environment
11. Detoxing the body — Western and TCM approaches
12. Treatment at my clinic
13. Frequently asked questions

1. Why mould exposure is so common in the UK

The UK has a perfect mould climate: high ambient humidity, mild winters, poorly ventilated post-war housing stock and a national habit of drying laundry indoors. A 2023 House of Commons report estimated that one in five UK homes has visible damp or mould, and the true figure including hidden mould (behind walls, under floors, inside ventilation systems) is much higher. The 2020 death of two-year-old Awaab Ishak from prolonged mould exposure brought the issue into national consciousness, but most affected adults remain unaware of why they feel unwell.

Several factors have made the problem worse over the last twenty years:

1. Tightened insulation — better energy efficiency means less air exchange, so moisture, mould spores and mycotoxins accumulate indoors rather than ventilating out
2. Modern construction materials — plasterboard, MDF and engineered woods feed mould more readily than older lime plaster and solid timber
3. Reduced heating in cost-of-living pressure — condensation forms on cooler walls and behind furniture
4. Hidden water ingress — slow leaks behind sinks, dishwashers, washing machines and shower trays can feed colonies for years
5. Climate change — warmer, wetter winters favour fungal growth

2. What is mould and what are mycotoxins?

Mould is a category of microscopic fungi that grows in colonies wherever there is moisture, organic material and a tolerable temperature. The mould species that most affect human health in indoor environments include:

1. Stachybotrys chartarum — the famous “black mould”, found behind walls and on damp drywall, produces trichothecene mycotoxins
2. Aspergillus species (A. fumigatus, A. flavus, A. niger) — common in dust, ventilation systems and food, produce aflatoxins and ochratoxin A
3. Penicillium species — the blue-green moulds on damp paper, books and old food; produce ochratoxin and citrinin
4. Cladosporium — common on bathroom tiles and window seals; a major airborne allergen
5. Alternaria — common in damp basements and air conditioning units; strongly allergenic
6. Chaetomium — secondary water-damage mould; produces neurotoxic mycotoxins

The substances mould produces that harm the body are called mycotoxins — small, fat-soluble, heat-stable compounds that the fungus uses to defend its territory against bacteria and other competitors. Inhaled, eaten or absorbed through the skin, these mycotoxins are taken up by the body’s tissues and accumulate, particularly in adipose tissue, the liver, kidneys, brain and bone marrow. Unlike infections, mycotoxin exposure does not require living mould in the body; the toxins persist long after the fungal source is gone.

3. Respiratory effects — the Lung takes the first hit

The respiratory tract is the front line of mould exposure. Spores and mycotoxins are inhaled with every breath. The Western medical picture includes:

1. Allergic rhinitis — persistent nasal congestion, post-nasal drip, sneezing fits, itchy eyes; often worse at home and better when away
2. Chronic sinusitis — ENT studies have found fungal organisms in over 90% of chronic sinusitis cases; the conventional surgical and antibiotic approach often fails to address the underlying cause
3. Asthma — mould is a well-documented asthma trigger; new-onset asthma in adulthood often dates from a move into a damp property
4. Allergic bronchopulmonary aspergillosis — a hypersensitivity reaction to Aspergillus that can mimic difficult-to-control asthma
5. Hypersensitivity pneumonitis — inflammation of the small airways from repeated exposure to mould spores; produces a dry cough, breathlessness and weight loss
6. Persistent hoarseness — the larynx is often irritated by airborne mycotoxins

If your sinus symptoms, cough or wheeze are worse at home or at work and improve markedly on holiday, mould should be high on your differential.

4. Immune and neurological effects (CIRS)

For a subset of people — estimated at around 25% of the population based on a genetic variation in HLA-DR — the immune system fails to recognise and clear mould biotoxins effectively. In these patients, biotoxins build up and provoke a low-grade chronic inflammatory response known as Chronic Inflammatory Response Syndrome (CIRS) or biotoxin illness. The syndrome was first described by Dr Ritchie Shoemaker in the early 2000s and is now an established (though not universally recognised) diagnosis.

CIRS produces a strikingly broad symptom picture, including:

1. Persistent fatigue out of proportion to activity — including post-exertional malaise
2. Cognitive dysfunction (“mould brain”) — brain fog, poor word-finding, memory lapses, slowed processing
3. Headaches and migraines, particularly on waking
4. Muscle aches, joint pain and morning stiffness
5. Anxiety, depression, mood instability and panic episodes
6. Multiple chemical sensitivity — reactions to perfumes, cleaning products, petrol
7. Light and sound sensitivity
8. Static electric shocks (a curious but well-described feature)
9. Persistent low body temperature, cold extremities
10. Hormonal disturbance — irregular periods, low libido, thyroid dysfunction
11. Insulin resistance and weight gain despite no change in diet
12. Tremor, vertigo and balance problems
13. Tinnitus
14. Vision changes — blurred vision, light flashes, “visual contrast sensitivity” deficits

These symptoms are routinely misdiagnosed as chronic fatigue syndrome, fibromyalgia, depression, anxiety disorder, IBS, perimenopause, “burnout” or simply “medically unexplained symptoms”. Many patients have been investigated extensively and told everything is “normal”. The mould connection is missed because it is not part of standard medical training.

5. The Chinese medicine view — external Damp invading the body

Traditional Chinese medicine identified the harmful effect of environmental damp on the body thousands of years before mycotoxins were isolated. In TCM, the body is vulnerable to six external pathogenic influences (the Liu Yin) — Wind, Cold, Heat, Damp, Dryness and Summer-Heat. Mould is the archetypal external Damp pathogen: it grows where there is moisture, it spreads slowly, and it produces a clinical picture that is heavy, sticky, and slow to clear.

External Damp has characteristic properties recognised in the classical texts:

1. Heaviness — producing a sensation of the head and body feeling weighed down, fatigue, sluggish thinking
2. Stickiness — the pathogen lodges in the body and is hard to dislodge, producing chronic, lingering disease
3. Turbidity — producing cloudy fluids: thick nasal mucus, sticky stools, cloudy urine, oily skin
4. Downward and inward movement — symptoms tend to settle in the lower body (oedema, vaginal discharge, lower back ache) and to penetrate deeper into the body over time

External Damp enters the body primarily through two routes:

1. Through the Lung — via inhalation of spores and mycotoxins. This is the most common route in mould-affected buildings and explains the prominent respiratory presentation.
2. Through the skin and pores — the “Wei Qi” defensive layer; explains the skin rashes, sensitivities and the “reactive when the weather changes” quality so many CIRS patients describe.

Once inside, Damp tends to settle in the Spleen, where it overwhelms the digestive transformation function. From here it disperses to wherever the body is weakest — the joints, the head (producing brain fog), the genitourinary system, the skin.

6. Chronic exposure — how Damp becomes Phlegm and Spleen weakness

If mould exposure resolves quickly, the body usually clears the Damp without lasting consequence. But chronic low-level exposure — weeks, months, years — produces three progressive changes that explain why some patients become so ill:

1. Damp transforms into Phlegm — the body’s metabolic heat slowly “cooks” the accumulated Damp into a thicker, stickier form. Phlegm in TCM is not only the visible mucus in the airways but also “invisible Phlegm” that obstructs the channels, mists the mind (brain fog) and forms nodules and cysts.
2. The Spleen is steadily weakened — constantly fighting accumulated Damp drains Spleen Qi. The Spleen produces less Qi and Blood, and the patient gradually develops the picture of Spleen Qi deficiency on top of the Damp accumulation: fatigue, poor appetite, loose stools, weak limbs, easy bruising, post-meal sleepiness.
3. The Lung becomes constitutionally weak — chronic Phlegm in the Lung produces a vicious cycle: weakened Lung Qi cannot disperse Damp, more Damp accumulates, the Lung weakens further. Patients catch every cold, take weeks to recover, and develop chronic productive cough or sinus congestion.

This sequence — external Damp → Damp accumulation → Phlegm formation → Spleen and Lung deficiency — is identical to what modern CIRS describes as the progression from acute exposure to chronic biotoxin illness. The two frameworks predict the same clinical course through different language.

7. Symptoms to watch for — a checklist

Mould exposure rarely produces one neat symptom; it produces clusters across multiple systems. If you have several of the following and they improve when you are away from home or work, mould should be investigated:

Respiratory and ENT

1. Persistent nasal congestion, post-nasal drip, chronic sinusitis
2. Allergic rhinitis worse indoors, better outdoors
3. Chronic dry or productive cough
4. New-onset adult asthma or worsening of existing asthma
5. Recurrent throat clearing, hoarseness
6. Recurrent middle-ear effusion in children

Cognitive and neurological

1. Brain fog, poor concentration, slowed thinking
2. Word-finding difficulty disproportionate to age
3. Headaches and migraines, particularly morning headaches
4. Tremor, twitching, restless legs
5. Anxiety, panic, mood instability
6. Light and sound sensitivity
7. Tinnitus
8. Vertigo and balance problems

Energy and immune

1. Persistent unrelieved fatigue
2. Post-exertional malaise (feeling crushed after activity)
3. Frequent colds with slow recovery
4. Multiple chemical sensitivities (perfumes, cleaning products)
5. Cold intolerance, low body temperature

Digestive and metabolic

1. Bloating, food sensitivities expanding over time
2. Irritable bowel syndrome with mixed features
3. Weight gain despite no dietary change
4. New insulin resistance

Skin and joint

1. Unexplained itchy rashes
2. Recurrent eczema not responding to usual treatment
3. Joint pain and morning stiffness
4. Muscle aches without clear injury

Hormonal and gynaecological

1. Irregular menstruation or absent periods (amenorrhoea)
2. Thyroid dysfunction (autoimmune Hashimoto’s often triggered or worsened)
3. Low libido and unexplained subfertility
4. Heavy menstrual flow with clots and brown discharge

8. Who is most affected

Some people are markedly more vulnerable to mould exposure than others. The most affected groups in my clinical experience are:

1. People with a genetic HLA-DR variation that impairs biotoxin clearance — estimated at 25% of the population
2. Women of reproductive age — hormonal cycles and the higher Spleen demand during menstruation make Damp accumulation more rapid
3. Pregnant women — the developing baby is highly vulnerable, and pregnancy already taxes the Spleen
4. Children — underdeveloped Spleens and rapidly developing immune systems are particularly susceptible (see Spleen vulnerability in children)
5. Older adults — reduced Spleen and Lung function, often combined with reduced ventilation in their homes
6. People with pre-existing autoimmune conditions — mould exposure frequently triggers flares of Hashimoto’s, lupus, MS and rheumatoid arthritis
7. Post-viral patients — long COVID, post-glandular fever and post-Lyme patients have a particularly poor tolerance for additional biotoxin load
8. Anyone with chronic chronic fatigue syndrome, fibromyalgia or chemical sensitivity — in whom mould is often the missing aetiological piece

9. How to detect mould in your home

Visible mould (the black or green patches on bathroom ceilings, around windows, behind furniture) is only the tip of the iceberg. The much larger problem is hidden mould behind walls, under floorboards, inside wall cavities, in HVAC systems and under shower trays. Steps to assess:

Visual and olfactory inspection

1. Look behind furniture against external walls, particularly north-facing walls
2. Inspect the back of wardrobes and inside cupboards on external walls
3. Lift floor coverings near skirting boards and check for staining or musty smell
4. Inspect bathroom ceilings and silicone seals, especially around the shower
5. Check under kitchen sinks and behind dishwashers and washing machines
6. Inspect window frames and lintels for condensation staining
7. Note any musty, earthy or “sweet” smell — mould often smells before it is seen

Air quality testing

1. ERMI (Environmental Relative Moldiness Index) — a dust sample sent to a specialist lab that uses PCR to identify and quantify the 36 most common indoor mould species; available through UK environmental testing companies
2. Air spore traps — sample airborne mould counts at different points in the property
3. Mycotoxin testing of urine — available privately (RealTime Labs, Great Plains Labs); shows whether mycotoxins are circulating in your body

Other red flags

1. You feel measurably better after a holiday or staying with relatives, and worse on return home
2. Multiple family members or housemates have unexplained chronic symptoms
3. Pets in the household have skin or respiratory problems
4. The building has had any history of flooding, persistent leaks, or condensation
5. Properties built or refurbished between roughly 1960 and 2000 with cavity-wall insulation retrofitted are particularly prone

10. How to remove mould from your environment

No amount of medical treatment, herbs or supplements will produce sustained recovery if you continue to inhale mould and mycotoxins. Removing the source is the first and most important step. In order of priority:

1. Identify and stop the moisture source — leaks, condensation, ground-water ingress. Without this, mould will simply regrow.
2. Improve ventilation — trickle vents open, extractor fans in bathrooms and kitchens used consistently, windows opened daily even in winter, dehumidifier running 24/7 in damp rooms (aim for 50–55% humidity)
3. Use a HEPA air purifier with a charcoal filter — the HEPA captures spores; the charcoal absorbs mycotoxins; run continuously in bedrooms and main living areas
4. Surface cleaning — for small areas (under 1 square metre), wear an FFP3 mask and clean with soapy water followed by a mould-killing product such as concrobium or borax solution. Do not use bleach on porous surfaces — it lightens the colour but the mould regrows
5. For significant mould (more than 1 square metre, or behind a wall) — engage a professional mould remediation company. Affected plasterboard, insulation and carpet need to be removed, not cleaned. Cheap surface cleaning leaves the mycotoxins in place and the colony grows back.
6. Vacate during remediation — disturbing mould releases huge spore loads. Stay elsewhere for at least the disturbance phase
7. Replace contaminated soft furnishings — carpets, mattresses, soft toys and books in heavily affected rooms hold mould and mycotoxins; replace, do not try to clean
8. Post-remediation testing — commission an ERMI or air sample after the work to confirm the property is now clear

11. Detoxing the body — Western and TCM approaches

Once the environmental source is addressed, the body still needs help to clear the mycotoxins and reverse the chronic Damp-Phlegm pattern. A combined Western and TCM approach is most effective.

Western approaches

1. Binders — cholestyramine, activated charcoal and bentonite clay bind mycotoxins in the gut and prevent reabsorption; use under medical supervision
2. Glutathione support — N-acetylcysteine (NAC), liposomal glutathione and sulphur-rich foods (broccoli, garlic, onion) support liver detoxification
3. Saunas — far-infrared sauna at 50–60°C, 3–5 times a week, for around 30 minutes, mobilises mycotoxins from adipose tissue and excretes them through sweat
4. Liver support — milk thistle, dandelion root, lemon water
5. Hydration — warm filtered water throughout the day to support kidney and lymphatic clearance
6. Avoid mouldy food — coffee, peanuts, dried fruit, nuts, corn and aged grains are common dietary sources of mycotoxins

TCM approaches

Chinese medicine treats mould-related illness as a Damp-Phlegm pattern with secondary Spleen and Lung deficiency. Treatment runs in two phases — first clear the Damp and Phlegm; then tonify the underlying weakness.

1. Acupuncture at points such as SP 9 (Yinlingquan) to drain Damp, ST 40 (Fenglong) to transform Phlegm, LU 7 (Lieque) and LU 9 (Taiyuan) to support Lung function, and ST 36 (Zusanli) and SP 6 (Sanyinjiao) to rebuild Spleen Qi
2. Moxibustion on the abdomen and lower back to warm and dry the interior, particularly useful in patients with cold limbs and chronic Damp
3. Chinese herbal medicine — classical formulas adapted to the individual pattern, often built around herbs such as Fu Ling (drains Damp), Bai Zhu (strengthens Spleen, dries Damp), Yi Yi Ren (drains Damp through urination), Cang Zhu (dries Damp), Yu Xing Cao (clears Lung heat-toxin) and Huo Xiang (transforms Damp aromatically)
4. Key formulas — Er Chen Tang (transforms Phlegm), Ping Wei San (dries Damp in middle Burner), San Ren Tang (clears Damp from all three Burners), Gan Lu Xiao Du Dan (clears Damp-Heat warm-disease patterns) and later, in the tonifying phase, Shen Ling Bai Zhu San and Yu Ping Feng San
5. Diet — warm cooked foods, no raw cold salads (see why salads can be bad in TCM), reduce or remove dairy and gluten during the active recovery phase (see gluten and dairy in TCM), avoid sugar and alcohol which feed Damp; include ginger, garlic, leek and pungent warming spices

Recovery from chronic mould illness is rarely fast. Most patients see meaningful improvement in 3–6 months and full recovery in 12–24 months, provided the environmental exposure has been removed. Patients who remain in mould-affected buildings rarely improve no matter how aggressive the treatment.

12. Treatment at my clinic

I treat the Damp-Phlegm patterns associated with mould exposure routinely at my clinic in Wokingham, Berkshire, using a combination of acupuncture, Chinese herbal medicine, dietary advice and lifestyle restructuring. Each patient’s formula is individually tailored after a full TCM assessment, because the picture — respiratory-led, neurological-led, immune-led, gynaecological-led — varies considerably between patients.

Online herbal consultations are available for patients throughout the UK and worldwide; this is often a practical option for mould-affected patients who find travelling difficult.

13. Frequently asked questions

I cannot smell any mould in my home but my doctor has run out of explanations for my symptoms. Could mould still be the cause?

Yes — hidden mould behind walls, under floors and in HVAC systems is common and rarely produces a smell that the occupants notice (because they become habituated). Visiting friends or relatives often notice a faint musty smell that the household itself cannot detect. The most reliable test is an ERMI dust analysis.

If I move out of a mould-affected property, will my symptoms resolve on their own?

Some patients do recover spontaneously after leaving exposure; others, particularly those with the HLA-DR variation that impairs biotoxin clearance, do not. The mycotoxins accumulated in adipose tissue continue to circulate and require active detoxification support. The Damp-Phlegm pattern in TCM does not clear on its own once it is established; it needs treatment to be reversed.

Is black mould (Stachybotrys) more dangerous than other moulds?

Black mould produces particularly potent neurotoxic trichothecene mycotoxins and is often singled out in the media. But many other moulds — Aspergillus, Penicillium, Chaetomium — produce mycotoxins that are just as harmful. The colour of the mould is not a reliable indicator of toxicity. Any significant indoor mould should be taken seriously.

Can mould exposure cause autoimmune disease?

Mould does not directly cause autoimmune disease, but it is a well-documented trigger of autoimmune flares in genetically susceptible patients, particularly Hashimoto’s thyroiditis, lupus, multiple sclerosis and rheumatoid arthritis. Addressing the exposure often improves the autoimmune disease alongside the other symptoms.

What about mould in food?

Dietary mycotoxin sources include coffee (particularly cheap commercial coffee), peanuts, corn, dried fruit, aged cheeses, beer and wine, and bread that has been in the cupboard too long. During active recovery from mould illness, reducing these and switching to specifically tested low-mould coffee can help reduce total mycotoxin load.

How long until I notice improvement once I leave a mouldy environment and start treatment?

Most patients notice some clear improvement within 4–6 weeks — usually in sleep, energy and brain fog. The respiratory symptoms often take longer (3 months or more) and the deeper Spleen and Lung weakness 6–12 months. Patience and consistency are essential; this is not a condition that resolves in a week.

Can babies and young children recover fully from mould exposure?

Children generally recover well from short to moderate mould exposure once the environment is corrected, because their developing systems still have considerable resilience. Long exposures during early development (the first three years) can have lasting effects on the immune and respiratory systems, but even these can be partially reversed with appropriate treatment.

Is mould testing on the NHS?

No — specialist mould and mycotoxin testing is privately funded in the UK. Costs typically run from £100 (a basic ERMI dust sample) to £400–£600 (a comprehensive urine mycotoxin panel). If you have visible mould in a rented property, your landlord is legally required to address it under the Homes (Fitness for Human Habitation) Act 2018.