If you struggle with dizziness, wheezing, itching or an upset stomach within minutes of drinking wine or beer, you could have sulphite sensitivity.
Doctors have told HuffPost UK they believe most people with a sensitivity to sulphites might not even know they have it.
Dr Kenny Livingstone, a registered GP and chief medical officer of ZoomDoc, explains that reactions to sulphites are uncommon and tricky to diagnose. “I suspect that most patients that have reactions to them are not even aware that these are potentially the cause,” he says.
Meanwhile Dr Clare Morrison, GP and medical advisor at Medexpress, believes sulphite sensitivity is “somewhat under-reported”, with symptoms being blamed on other causes such as asthma.
So what is it – and how do you know if you have it?
What Are Sulphites?
Sulphites have been used for decades in food and drink to preserve flavour and colour, and also to stop it spoiling. They are one of the 14 allergens that need to be labelled as part of the European Food Information to Consumers (FIC) Regulation – this is if the food contains sulphur dioxide or sulphites at levels above 10mg per kg or per litre.
They are found in wine vinegar, fermented foods, sauces, processed potato, Maraschino cherries, jams, jellies, some dried fruits, seafood and some bread, biscuits and pizza dough. They can also be found in processed meat, such as sausages and burgers.
Grape juice, some soft drinks, wine and beer also contain sulphites. They occur naturally, to help inhibit the growth of harmful bacteria in those beverages.
What Are The Symptoms Of Sulphite Sensitivity?
The occurrence of sulphite sensitivity in the general population is thought to be less than 2%, but this rises to between 5-13% in asthmatics. Sulphite allergy is very rare, but those who are will have more extreme symptoms and reactions.
Those with asthma, eczema or hay fever may be more at risk of a sulphite sensitivity, according to Dr Arun Thiyagarajan, medical director for Bupa Health Clinics, and subsequently might experience symptoms such as wheezing, coughing, or hives, which is a red, raised itchy rash.
Other symptoms include general itchiness, upset stomach, rhinitis (a clear runny nose, sneezing, blocked or itchy nose), diarrhoea, flushing and dizziness.
Bodily reactions to sulphites can range from mild to severe, explains Dr Morrison, and can vary from person to person. There have been reported deaths, she says, though fortunately these are very rare.
How Is It Diagnosed?
It’s tricky to diagnose sulphite sensitivity or allergy. “Allergy testing for sulphite intolerance isn’t something that the NHS routinely offers, because such tests aren’t thought to be particularly reliable, or helpful,” says Dr Morrison.
Generally, the diagnosis is made by looking at what foods seem to trigger a reaction, she explains.
If you suspect you might be reacting to sulphites, both Dr Morrison and Amena Warner, Allergy UK’s head of clinical services, recommend keeping a food diary to show to your GP, which can help with the diagnosis.
“There are no validated tests for sensitivity apart from a trial elimination to see if the symptoms resolve.”
A food exclusion and reintroduction diet may be suggested, says Dr Thiyagarajan, which involves removing foods high in sulphites for a set period of time and then slowly re-introducing them into your diet to see if they cause symptoms.
“There are no validated tests for sensitivity apart from a trial elimination to see if the symptoms resolve,” adds Warner.
When To Get Urgent Help
If you have symptoms of sulphite sensitivity or allergy, read food labels carefully and avoid those containing sulphites.
In severe cases, sulphites can cause anaphylaxis, which can be life-threatening if not treated quickly. People who experience a rash anywhere on the body, or symptoms such as swelling in the face, throat or mouth, difficulty breathing, nausea and vomiting, should seek emergency care immediately.
For more information on sulphite allergies and sensitivities, visit the NHS website.