It’s being blamed for a range of health problems – from itchy eyes and sensitive skin to breathing difficulties and gut problems such as bloating or diarrhoea. So are you, too, suffering from ‘mould toxicity’, as many influencers now claim?
These are just some of the ‘warnings’ popping up on social media that mould-containing foods – which includes sourdough bread, blue cheese and kimchi – can trigger food allergies, intolerances or ‘toxicity’ symptoms.
Influencers – ranging from holistic health coaches, nutritional therapists or just people now following highly restrictive diets after self-diagnosing – claim that mould in food is the trigger for a range of health problems.
In a post by Mari Llewellyn (@pursuitofwellnesspodcast), she interviews a nutritional therapy practitioner who warns against moulds not just in coffee but also grains, raw fish (sushi) and certain fruits and vegetables.
TikTok ‘holistic health coach’ @LeiahR says you may benefit from giving up coffee, wine, bread, peanuts and mushrooms.
Meanwhile, @pickyhands on TikTok advises viewers to ‘stop sipping on mould for fun, then wonder why you have issues in your body’ – pointing to the fact that many drinks contain citric acid (a preservative), which can be derived from mould.
In fact, the list of foods to avoid may be even more extensive, according to some influencers.
It goes without saying that most of us would avoid eating foods that have gone mouldy, but some of those being highlighted now are foods that naturally contain mould – which is not necessarily visible nor harmful.
According to TikTok ‘holistic health coach’ @LeiahR, you may benefit from giving up certain ‘mould-containing’ foods, such as wine or bread
Influencers are blaming mould-containing foods for many health ailments
Moulds are a type of fungus (e.g. yeast) and are naturally present in many foods – in fact, they are pretty hard to avoid. For example, they’re naturally found in bread, kombucha, wine and beer, but also fermented cheeses, pickles, dried fruits, coffee and mushrooms.
Moulds can also be added to some foods, to improve taste: the Botrytis cinera fungus, for instance, is used in wine making to reduce grapes’ water content and enhance sweetness – and the Aspergillus niger fungus is used to make citric acid, added to many drinks, for example, as a preservative.
But now influencers are suggesting that common health problems and symptoms could be due to mould toxicity from day-to-day food and drink. It is also being suggested that some people – particularly those with an established allergy to airborne mould – may also react to moulds in food they eat.
But medical experts are deeply sceptical.
‘Although people can develop allergic symptoms such as itchy or swollen eyes and allergic asthma from breathing in mould spores, this is not connected to foods, but from the environment, such as damp poorly ventilated buildings,’ says Dr Jose Costa, an allergy consultant at the Children’s Allergy Clinic in the West Midlands and an honorary clinical lecturer in allergy at Warwick Medical School.
‘Moulds are in so many different foods, there is no known mechanism for suggesting that they can cause allergy or intolerance symptoms – and no published evidence suggesting that cutting out these foods can improve symptoms,’ he says.
In fact, moulds are a part of a healthy gut microbiome – the community of bugs, including bacteria and viruses, that live in our guts, and that are linked with many aspects of our health.
‘And a lot of the foods that we are encouraged to eat for a healthy gut are fermented foods, which contain moulds – including natural yoghurt, cheeses and sourdough bread,’ says Dr Costa.
Wellness posts also suggest that some people – particularly those with an established allergy to airborne mould – may react to moulds in food they eat
Indeed, if moulds were as problematic as these influencers suggest, we would be seeing large-scale issues and more patients showing up in clinics with allergies – which they are not, he says. (He notes that some people are genuinely allergic to mushrooms, for example, which are a type of fungi, but this is rare and usually relates to certain types of mushroom only.)
‘Where people do report allergic symptoms, it’s possible they are reacting to another ingredient in the food,’ he suggests – such as lactose (a milk sugar) in cheese, or histamine.
It might well be that it’s not mould but some other element of food that is causing a reaction, agrees Chloe Hall, a spokesperson for the British Dietetic Association and who runs the Calm Gut Dietitian (an online clinic for food intolerances).
‘Anecdotally, some people with [airborne] mould allergies do say they also react to foods such as mushrooms or those containing yeast – but it’s quite rare,’ she adds.
Amena Warner, head of clinical services at the charity Allergy UK, says the mould allergy symptoms are respiratory or allergic rhinitis type symptoms such as wheezing and itchy swollen eyes, and connected to airborne mould spores found in damp buildings, rather than food.
‘You do sometimes get a powdery green mould on decomposed food that can become airborne and can cause allergic symptoms – but this is triggered by the airborne particles that you breathe in, not by eating it,’ she says.
There is one potential, although very rare, type of allergic reaction to mould in food: the charity Anaphylaxis UK says a tiny number of people have been found to react to the meat substitute product Quorn, which is made of mycoprotein (a fungal protein derived from the fungus Fusarium venenatum, a type of mould), although this is rare (one analysis by an expert panel convened by Quorn’s maker, Marlow Foods, found there was one case of illness for every 1.85 million servings of Quorn over 15 years).
Annette Weaver, clinical dietetic adviser at Allergy UK, says people with mould allergy may be at higher risk of developing an allergy to mould-related foods (mushroom, yeast, mycoprotein, fermented foods), but this is very rare.
‘People should not assume that they will have reactions to food because they react to mould in the environment and should not restrict their diets unless under the advice of a qualified health professional,’ she says.
‘Research suggests that mould may activate the immune system without allergy being present.’
For some people, it is possible that this might contribute to food intolerance reactions, but evidence for this is lacking and more research is needed, she adds. ‘For most people, eating fermented foods contributes to good health.’
Although there are skin and blood tests for airborne mould allergy, which allergy clinics can do, Chloe Hall says there is no test for mould intolerance – if, indeed, it is even a ‘thing’. The only way someone might identify if they have an intolerance to a food is to keep a food diary to see what triggers symptoms.
* See allergyuk.org
[Notigroup Newsroom in collaboration with other media outlets, with information from the following sources]
