The following 13 questions are among those frequently asked by food allergic people or their carers, through calls made to the Anaphylaxis Campaign helpline. Our answers have been reviewed by experts in the medical field and food industry.Are children with nut allergy at risk from conkers?
A few schools have banned games with conkers because they are worried they will endanger pupils with nut allergy. However, we can find no credible reports suggesting that conkers pose any risk to people with nut allergy.
Staff operating our telephone helpline have heard a few anecdotal reports from people saying they have skin reactions to conkers when they handle them. Our lead medical reviewer believes this to be a rare problem occurring equally in people with and without nut allergy. Clearly if this happens, they should be avoided. No one should be eating them as they are poisonous in their own right.
Because of its name, many people with nut allergy believe that nutmeg must be avoided at all costs. They are almost certainly being over-cautious because there is no hard evidence to suggest that people with nut allergy are particularly at risk from nutmeg, and the incidence of nutmeg allergy is rare. However, not enough research has been carried out to be certain about how much of a problem it is. If you are allergic to nuts and have never had a reaction to nutmeg it is likely that nutmeg poses no greater risk than many other foods.
The most common oils used in the UK are derived from rapeseed, sunflower seed, soya, maize, palm and palm kernel. Where these oils appear in pre-packed food, they are likely to have been refined — a process that removes almost all traces of proteins (the components of a food responsible for triggering allergic reactions). There is some research to support the view that refined vegetable oils are safe for people with food allergies. For example, a project carried out in Southampton showed that refined peanut oil will not cause allergic reactions for the majority of people with peanut allergy and if anyone does suffer a reaction it is likely to be mild (Hourihane et al 1997). A more recent study confirmed the amounts of protein found in refined peanut oil do not trigger reactions in people allergic to peanuts.
With the exception of sesame oil (see below), it is highly unlikely that vegetable oils, when refined, will cause allergic reactions. However, to be absolutely certain about this, research would have to be undertaken on every oil. Some speciality oils, for example sesame and other nut oils like hazelnut and walnut, may contain some unrefined oil for flavour purposes and certainly do present a risk.
(The above text was checked for accuracy by the Seed Crushers and Oil Processors Association)
The reason that sesame oil poses a risk to people who are sesame allergic has recently become clear. A French study has shown that in addition to allergy-provoking proteins present in the aqueous (water-soluble) part of the seed (as is the situation with nuts and other seeds), in the case of sesame seed allergy there are additional allergy-provoking proteins called oleosins that are present in the oily (fat-soluble) part of the seed.
The same study showed that allergy to these proteins is missed by standard allergy tests. Until scientists have devised a reliable allergy test for these proteins, there will continue to be about one in four cases of suspected sesame seed allergy that have completely negative sesame allergy tests, meaning that the diagnosis will need to be confirmed by a hospital-supervised food challenge, where small amounts of the food are eaten to test whether a reaction occurs. Anyone who has, or who suspects, sesame seed allergy should avoid sesame oil as well as sesame seeds and sesame products.
For more information, read our Knowledgebase article on vegetable oils.
The tendency to be allergic runs in families. If one family member has a food allergy (father, mother or a child), then all children in the immediate family will also be susceptible to allergies and could possibly become allergic to something. This will not necessarily be an allergy to the same foods as others in the family, and it does not necessarily follow that if one family member has an allergy that is severe, any other allergies in the family will also be severe.
The Campaign knows of a small number of cases where touch or smell caused severe reactions for people with peanut allergy. However, some reassurance can be gained from an American study. Researchers observed 30 children with severe peanut allergy while they were being exposed to peanut butter through touch and smell. Accidental contact was simulated by pressing a dab of peanut butter on the child’s back for one minute, and by holding a dish containing three ounces of peanut butter one foot from the child’s nose for 10 minutes.
- None of the children experienced anaphylaxis.
- There were no reactions to inhalation.
- During the touch part of the study one-third of the children had a mild reaction, such as redness, itching, or a single hive limited to the site of contact. Medication was not needed to treat these reactions.
The researchers concluded that at least 90 per cent of children with the same severity of peanut allergy would not experience a severe reaction to similar exposures. They emphasised that the study looked at peanut butter but not peanut in other forms.
We strongly advise that people with peanut allergy should discuss their own individual case with their allergy specialist before changing their allergen avoidance measures.
In our experience, the number of people with peanut allergy who react to other legumes (such as soya, peas, chickpeas, fenugreek, beans and lentils) is relatively small and this is supported by research from the USA. Care is needed, but most people find they can tolerate other legumes without problems. It is important to raise this with your allergy specialist for specific advice.
The use of “may contain” warnings is voluntary and not directly covered by food labelling law. Nevertheless, the industry is well aware that the General Food Law places a requirement on manufacturers to communicate any risk to consumer health following the consumption of their product.
Many people find “may contain” warnings annoying because they limit choice and make shopping complicated, but often these warnings are there for a good reason because of the risks of cross-contamination during the production chain. Our advice to people is clear: Don’t ignore these warnings. You may eat a product numerous times without having a reaction but the next time you may not be so lucky. Cross-contamination can be intermittent. Research has shown that the greatest risk of cross-contamination occurs with snack foods.
Although research is ongoing, there is no evidence at present to suggest that mothers who eat peanuts while pregnant or breastfeeding will increase the risk of their child becoming allergic to peanuts. This includes women in “high risk” families — that is, where there is already allergy.
Guidelines issued by the European Academy of Allergy and Clinical Immunology (EAACI) state: “The advice for all mothers includes the consumption of a normal healthy diet without restrictions during pregnancy and lactation (breastfeeding)”.
The companies that produce the three adrenaline injectors available in the UK also produce “dummy” devices for people to practice with. The details are on their websites:
Each of the 3 brands in the UK (EpiPen, Jext and Emerade) do have different needle lengths but all of them have shown through testing that is required as part of their license from the European Medicines Agency (EMA) and the Medicines and Healthcare Products Regulatory Agency (MHRA) that they are safe and effective.
Adrenaline auto-injectors provide an effective dose of a life-saving medicine which long clinical experience has shown to be effective in treating the symptoms of anaphylaxis. As well as injecting adrenaline, the person should lie flat with their legs up to keep the blood flowing, unless having difficulty breathing, in which case they may need to sit up to make breathing easier. Adrenaline acts quickly to open up the airways, reduce their swelling and raise the blood pressure. To work effectively, it must be given as soon as possible if there are any signs of a severe allergic reaction. With early treatment those more severe symptoms are easier to reverse, so the important message is to use adrenaline as soon as severe symptom starts as it is a very safe and effective drug. In the UK there are three different doses of AAI’s available. Jext® available in 150 or 300mcg, EpiPen® available in 0.15mg and 0.3mg and Emerade® available in 150 micrograms, 300 micrograms and 500 micrograms. The decision regarding which dose an individual should be prescribed should be made by an allergy specialist. Our advice is always to carry two adrenaline auto-injectors with you at all times.
As the need to use an adrenaline auto-injector is unpredictable and infrequent, allergic individuals may neglect to check their medication and expiration date. There are currently no published data on the proportion of individuals with expired auto-injector devices, but an audit of insect sting emergency kits, which contained an adrenaline auto-injector device, reported that more than half of the kits were out of date.
Although far from ideal, in situations when the only adrenaline auto-injector available is an outdated one, experts have advocated this should be used providing no discolorations or particles are apparent as these changes would indicate the adrenaline had degraded. Therefore, most adrenaline auto-injector devices (e.g. Epipen, Emerade, Jext) now have an inspection window that allows for the visual inspection of the condition of the adrenaline solution.
This article has been reviewed by Dr Michael Radcliffe, Consultant in Allergy Medicine, University College London Hospitals NHS Foundation Trust. We are not aware of any conflicts of interest in relation to his review of this article.
Other experts in various fields were asked for their opinions on specific sections. These included a representative of SCOPA, the Seed Crushers and Oil Processors Association (section on vegetable oils). The author felt it relevant to record this as SCOPA is a trade body.
All the information we produce is evidence based or follows expert opinion and is checked by our clinical and research reviewers. If you wish to know the sources we used in producing any of our information products, please let us know, and we will gladly supply details.
Disclaimer – The information provided in this Factsheet is given in good faith. Every effort has been taken to ensure accuracy. All patients are different, and specific cases need specific advice. There is no substitute for good medical advice provided by a medical professional.
About the Anaphylaxis Campaign: Supporting people with severe allergies
The Anaphylaxis Campaign is the only UK wide charity to exclusively meet the needs of the growing numbers of people at risk from severe allergic reactions (anaphylaxis) by providing information and support relating to foods and other triggers such as latex, drugs and insect stings. Our focus is on medical facts, food labelling, risk reduction and allergen management. The Campaign offers tailored services for individual, clinical professional and corporate members.
Publication date: July 2019
Review date: July 2022