Sesame Allergy; Everything We Know So Far

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Sesame is a flavoursome seed and a popular ingredient in many Eastern cuisines. Its high nutritional value has made it an increasingly common addition to a wide range of baked goods, vegetarian dishes and health foods all over the world. Unfortunately for those who are allergic to it, it can take less than one seed to provoke reactions, and those reactions can often be quite severe. The sesame-allergic should also be aware that the use of sesame seed in cosmetics and pharmaceuticals has been increasing over the past few years and that reactions have been reported to sesame in both Indian traditional herbal (Ayurvedic) medicinal oils and Traditional Chinese Medicine (TCM) topical medicine.

And now for the details, which include:

What is an allergy to sesame?

Sesame (Sesamum indicum L.) is an oil seed plant of the family of Pedaliaceae (Sesame family). The genus Sesamum is made up of about recognised 35 species, but the only widely cultivated one is Sesamum indicum. There are another 6 partially cultivated species; S. radiatum (India, Sri Lanka, Africa), S. angustifolium (Congo, Uganda, Mozambique), S. occidentale (Africa, India, Sri Lanka), S. calycinum (Angola, Mozambique) and S. bauymii (Angola). All of the other species are wild. Nine of them can be found in peninsular India, and the rest in sub-Saharan Africa.

Sesamum indicum is one of the earliest human production and consumption crops, and its seeds have been used by humans since ancient times as a food and medicine. The sesame plant is thought to have originated in Asia or East Africa, but the cultivation of sesame is thought to have started in India and later spread to Mesopotamia and then to Babylonia, Egypt, China and Europe.

Worldwide production and consumption of sesame has massively increased in recent years. Asia and Africa, where sesame is an important part of the diet, grow almost 97% of the world’s sesame seed crops.

In 2018, Tanzania was the world’s leading consumer of sesame followed by China, Sudan, Myanmar, India, Ethiopia and Nigeria. Altogether, those countries consume almost 74% of the world’s sesame. The world’s biggest producers were India, Myanmar, China and Tanzania.

In 2021, the top exporters of sesame were India, Sudan, Niger, Ethiopia and Nigeria. The top importers were China, Turkey, Japan, South Korea and Greece.

Sesame can have white, black sesame or yellow seed hulls, the first two of which are the most extensively grown versions. Unhulled seeds are pale and almost translucent.

The seeds are rich in protein, minerals, vitamins, dietary fibre and fat. Lots of fat. Sesame has the highest oil content of all the major oil crops, with seeds containing up to 61.7% fat, much of which is unsaturated fatty acids including linoleic acid and linolenic acid, both essential fatty acids that cannot be synthesised in the body.

Sesame seeds are consumed whole, used to produce paste and oil, or added to food products like processed meat, ready meals and fast-food. They are widely used in the baking industry, where they function as nutritional enhancers, thickeners, binders and toppings for a variety of breads and pastries. In Europe, sesame has become an important ingredient in vegan and vegetarian cuisine.

The oil obtained from the seeds is used for cooking or salad oil. Because it’s rich in polyunsaturated fatty acids, it can be used to make healthy fat products like margarine and shortenings. The seed hulls are also high in antioxidants and can be combined with other vegetable oils to produce blends with both a good balance of essential fatty acids and oxidative stability.

Sesame is also widely used in the cosmetic industry, where it is used to make creams, moisturisers and soaps, and the pharmaceutical industry, where it is used to make ointments and massage oils, as well as functioning as a solvent for medications and intramuscular injections.

Unfortunately, sesame can cause allergic reactions in a small percentage people. This happens because their body’s immune system mistakes one or more harmless sesame proteins for toxic invaders and creates IgE antibodies against them. The next time they eat sesame, the antibodies recognise the proteins and prompt a response from immune system cells. These, in turn, release a variety of chemicals into the bloodstream, including histamine, the chemical that is primarily responsible for the symptoms of allergy.

Reports of allergic reactions to sesame seeds and oil started appearing in the 1950s and rapidly increased in following decades, due both to the increased exposure to sesame-containing food products, cosmetics and medications in Western countries, and to the increased awareness of potential allergic reactions.

The demonstrated allergenicity of sesame, together with the high risk of accidental exposure in foods, cosmetics and pharmaceuticals, resulted in mandatory food labelling in several countries, including the European Union, where sesame has been listed as one of the top 14 food allergens since 2006. Sesame was added to the list of major allergens in the US on January 1st, 2023.

Identified allergens

The proteins (and occasionally carbohydrates) in a food that are capable of provoking allergic reactions are called allergens. Allergens are named using the first three letters of the genus—Sesamum—the first letter of the species—indicum—and a number reflecting the order in which they were identified.

As of March 2026, 7 sesame allergens have been added to the WHO/IUIS allergen database (the official, peer-reviewed database of allergens maintained by the World Health Organisation and International Union of Immunological Societies)

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How common is sesame allergy?

A definitive diagnosis of allergy can currently only be established with a food challenge, but challenges are costly in terms of both time and resources, as well as potentially risky. So many prevalence studies measure sensitisation—using skin or blood test data—but sensitisation is not allergy. Being sensitised to something simply means that your immune system recognises it, but you may not actually react to it; in fact, many people don’t react to whatever it is they are sensitised to. Studies that use sensitisation data therefore tend to produce allergy prevalence numbers that are larger than they should be.

In a similar vein, studies that estimate allergy prevalence using questionnaires usually produce somewhat inflated numbers as people can self-report allergies that they do not actually have, although robust studies will use certain criteria to evaluate respondents’ answers and determine whether their symptoms suggest an allergy or not.

IgE-mediated allergy

Research has put the global prevalence of sesame allergy at between 0.1% to 0.2% of the general population. It’s thought to be the most common trigger of reactions among the edible seeds, primarily because it’s in so many foods.

But prevalence numbers vary according to local customs and eating habits.

Sesame and products derived from sesame are widely available in a range of products in and around the Middle East, so the highest prevalence rates can be found there.

Sesame and products derived from sesame are widely available in a range of products in and around the Middle East, so the highest prevalence rates can be found there.

In Israel, a 2019 study reported the prevalence of sesame allergy among young adults to be 0.09% and a 2020 study on children reported that sesame was the third most important food allergen after milk and eggs, determining the prevalence to be 0.93%, which was about the same as the last time it was measured around 2 decades previously.

In Lebanon, a 2011 study put the sensitisation to sesame among infants, children and adults at 3.9%, 2.65% and 1.9%, respectively.

In Turkey, sesame seeds are the fourth most common food trigger among infants, affecting 1 in 5, and seeds are the third most common food trigger among older children, behind tree nuts and milk.

Outside of the region, sesame is increasingly being recognised as a common food allergen. In Europe, data is scarce, but the 2019 Pronuts study, which looked at the prevalence of allergy to tree nuts and sesame seeds in children aged 16 and under in 3 European centres (London, England, Geneva, Switzerland and Valencia, Spain), found that 7 of the 50 (14%) patients in London and 5 of the 42 (12%) patients in Geneva, had sesame allergy. None of the patients in Valencia did.

European researchers have also revealed that, although adults are more likely to have pollen-related food allergies, when it comes to food allergens that do not cross-react with pollens, sesame is the one that they are most likely to be sensitised to.

In the US, where sesame has become quite popular thanks to health-conscious consumers and popular ethnic foods like hummus and tahini, a nationwide telephone survey carried out in 2008 determined that 13 of the respondents—0.1% of the total people surveyed—had a convincing history of reactions to sesame. A 2019 study using telephone and web-based surveys determined that up to 0.49% of Americans might have an allergy to sesame, although just 0.23% of them had a history of convincing symptoms to sesame.

In Canada, a nationwide telephone survey carried out in 2010 estimated the prevalence of probable sesame allergy (based on convincing history or a doctor’s diagnosis) to be around 0.09% of the general population.

A 2015 study of people in four cities of the metropolitan area of Guadalajara, Mexico, reported a probable prevalence of sesame allergy of 0.1%.

In the 1990s, as Australians started eating more sesame, sesame allergy was linked to an increase in eczema and anaphylaxis among infants and was reported to be the fourth most common food allergen among children, more common than an allergy to any one tree nut. A 2011 study that examined 1-year-old infants in Melbourne put the prevalence of ‘clinically relevant’ sensitisation (i.e. more likely to indicate a potential allergy) at 1.6% and of actual allergy at 0.8%. A 2017 study put the prevalence of sesame allergy in Australian 4-year-olds at 0.4%.

In Asia, where sesame is a common food ingredient, allergy to the seeds appears to be rare, with the exception of Singapore, where 3.7% of food-allergic children were found to be sensitised to sesame. There are no reports on sesame allergy from China, India or other countries in the region where it is commonly grown and eaten.

Non-IgE-mediated and mixed allergies

Research concerning sesame-induced non-IgE-mediated or mixed allergies is almost impossible to find.

One type of mixed allergy that’s associated with sesame is atopic dermatitis (AD), aka allergic eczema, which I shall now just call eczema (although, strictly-speaking, AD is the most common subtype of eczema).

About 2.6% of the global population is estimated to be affected by eczema, which is just over 204 million people. It’s a condition that’s more likely to affect young children and females, and food is thought to be a trigger in 20% to 30% of the cases, with the most common allergens being milk, egg, soy, wheat, peanut and fish.

Although food-triggered eczema affects children more than adults, quite a few adults still have the condition. The prevalence of food allergy in children with eczema is estimated to be somewhere in the range of 15% to 30% and the prevalence of food allergy in adults with eczema is thought by most experts to be between 1% and 3%, with between 9% and up to 24.5% of that number estimated to be new, adult-onset cases.

There aren’t any prevalence numbers focussing on sesame-induced eczema but, even though it’s not considered a common trigger, it still seems to cause problems in some populations. A recent study of 84 Turkish sesame-allergic children reported that just over a third—32 (38%)—of them had early-onset, moderate or severe eczema and had been diagnosed with sesame allergy after going to a doctor to try and determine what was causing their chronic skin condition. After eliminating sesame from their diet, their skin got significantly better (which is how they were diagnosed in the first place).

Experts do not know the exact prevalence of food protein–induced enterocolitis syndrome (FPIES) but it’s estimated to occur in the general population at a prevalence ranging from 0.015% in Australia to 0.7% in Spain and reports of cases have been on the increase in recent years, either because of an increase in new cases or because of an increased awareness of the condition among doctors.

Cases of eosinophilic oesophagitis (EoE) are also reported to be on the increase since the turn of the century, probably because the condition is better recognised. EoE is now thought to affect 1 or 2 people in 2000 but, in people who have food allergies, the number is more like 1 in 20. EoE to a food often develops in someone who already has a standard, IgE-mediated allergy to that food.

According to American survey data collected between 2015 and 2016, people who are allergic to sesame are significantly more likely to have eosinophilic oesophagitis (EoE) and food protein–induced enterocolitis syndrome (FPIES (3.6% and 4.4%, respectively, in this group of 251 people with convincing allergy) that people with allergies to other common trigger foods.

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Will it go away?

IgE-mediated allergy

Sesame allergy typically manifests in very early childhood. In fact, children often seem to react on their first taste of sesame; the Australian HealthNuts study that examined the prevalence of food allergy in infants reported that only 12.5% of those diagnosed with sesame allergy had actually eaten sesame before. This implies that they become sensitised through breastfeeding.

Another Australian study reported that 60% of the infants that they diagnosed as being sensitised to sesame during a 6-year period were under 24 months old. The researchers also described the case of an 11-month old infant who developed facial swelling, hives and wheezing after his first taste of tahini, which his mother had eaten throughout her pregnancy and while breastfeeding.

The average age at diagnosis is 1 year old in Israeli and Turkish children, 3.5 years old in American children and 5 years old in French children, reflecting the age at which sesame products tend to be incorporated into children’s diets in different cultures.

But people can develop an allergy to sesame at any age; onset has been reported anywhere between infancy and 65 years old. According to a 2019 review of web- and telephone-based food allergy questionnaires carried out in America, 1 in 4 sesame (25.7%) allergies develop during adulthood.

Whatever the age of onset, the prognosis for people with sesame allergy does not look good, with only between 1 in 3 and 1 in 5 children outgrowing the disease and no reported cases of adult-onset allergies resolving.

Studies of Israeli infants and children have reported that it tends to resolve in 20% to 30% of cases. A 2021 study that followed 190 sesame allergic children for almost 4 years reported that 61 (32.1%) of them outgrew the allergy.

Similarly, a French study that followed 14 sesame-allergic children for up to 6 years reported that 3 (21.4%) of them outgrew their allergy.

And a recent analysis of the medical records of 84 sesame-allergic Turkish children reported that only 18% had outgrown their allergy by the time they saw their allergist for their final visit, with the average child outgrowing their allergy around the age of 5 and a half. One of them, however, was only found to have become tolerant to sesame at the age of 18, highlighting the fact that, although rare, an allergy to sesame can be outgrown after childhood, so it may pay to have a check-up if you’ve not had a reaction for a while.

According to the studies that have followed large groups of children for several years, an allergy to sesame is more likely to be persistent if:

• you are older when you have your first reaction
• you are allergic to peanuts and/or tree nuts as well
• your reactions are more severe
• the skin test response after your first reaction produced a large weal
• your skin and/or blood tests show a high level of IgE antibodies which doesn’t decrease over time

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Cross-reactions to sesame

TTechnically-speaking, a person can be allergic to sesameand another food (or foods, or aeroallergen(s)) either by cross-reactivity—the immune system mistakes the proteinin one allergen for aprotein with a similar structure inthe other—or by an independent sensitisation to each food and/or aeroallergen(a co-sensitisation or co-allergy), in which case the immune system has developed specific IgE antibodies against each allergen. It can be difficult to determine whether reactions are caused by cross-reactions or co-allergies,but the end result is the same; problems, problems.

People who are allergic to sesame are often sensitised or allergic to peanuts and/or tree nuts

For example, when 150 sesame-allergic members of the British Anaphylaxis Campaign were surveyed, 84% of them reported being also allergic to nuts or peanuts. Similarly, a European study reported that 61% of the sesame-allergic patients seen at centres in England, Spain and Switzerland were also allergic to peanut and/or tree nuts.

The latter study also revealed that people with sesame allergy are 9.1 times more likely to be allergic to pine nuts and 4.8 times more likely to be allergic to Brazil nuts than those without sesame allergy. People with macadamia nut allergy are also 8.8 times more likely to have sesame allergy than people who are not allergic to macadamias, and those with hazelnut allergy are 3.6 times more likely to be allergic to sesame.

In the US, one study reported that, of the 69 children that were found to be sensitised to sesame during a 2-year period at one centre, 84.8% were also sensitised to peanut, 82.9% to hazelnut, 80.6% to walnut and 76.3% to almond. Another study reported that, of the 15 children diagnosed with sesame allergy during their investigation, 93.3% were sensitised to peanuts and all of them to at least one tree nut.

The high degree of cross-reactivity between sesame and (pea)nuts is due to the structural similarity between their allergens, notably the storage seed proteins 2S albumins, 7S globulins and 11S globulins, as well as the oleosins.

However, just because the potential for cross-reactivity between 2 foods has been established in a test tube does not necessarily mean that you will have allergic reactions to both foods.

In a study that examined the relationship between peanut and sesame allergy in children, researchers determined that, although children who were allergic to peanuts may have a higher chance of being sensitised to sesame than children with other food allergies, there did not appear to be a relationship between having a history of reactions to peanuts and having reactions to sesame.

According an American study, for a nut-allergic child to have a real risk of symptomatic allergy to sesame, they have to have already experienced reactions to both peanuts and tree nuts.

(And for the record, even though coconuts used to be included in the ‘nut’ allergy list in America, they aren’t actually nuts (they are fruit, more specifically, drupes—a fruit with a hard layer surrounding the seed), and being allergic to coconut does not increase your risk of developing cross-reactions to sesame or (pea)nuts.)

Although you might imagine that being allergic to one type of seed means that you will have problems with other types of seeds, this isn’t necessarily the case.

Although one study has reported potential cross-sensitisation between sesame seeds and chia seeds, this was done in a lab test that demonstrated a similarity between certain proteins, rather than showing a sensitisation in an actual human. Another study has also demonstrated the potential for cross-reactivity between sesame and poppy seed (as well as hazelnut, kiwi and rye grain), again in test tube.

In a study of 106 American children with a proven sesame allergy, 62% were found to have a co-sensitisation to peanuts and/or tree nuts, but the rate of co-sensitisation towards other seeds (sunflower, poppy, flaxseed, chia and mustard) barely reached 9%, a statistically insignificant difference compared to sesame-tolerant children.

That said, a 2013 British study which looked at 42 children with a suspected sesame allergy found a significant association between having sesame allergy and an allergy to other seeds, especially poppy seed (which 16.7% of the children reported symptoms to). The study, however, relied on questionnaire data rather than on testing.

However, the risk of experiencing cross-reactions to new nuts and seeds seems to grow as one gets older. A study of 84 sesame-allergic Turkish children reported that, by the time they visited the allergist for the last time. 48 (57.1%) of the children were also allergic to tree nuts and 21 (25%) to other seeds including poppy, sunflower, pumpkin, and mustard). The authors highlighted previous research showing that children who are allergic to peanuts or tree nuts in early childhood have a tendency to develop multiple allergies to other nuts and seeds over time, implying that children who are first diagnosed with sesame allergy will experience the same thing.

This idea is also backed up by the results of an Australian study that determined that children who didn’t outgrow their allergy to peanuts were more likely to eventually develop an allergy to sesame than those who did, even if they followed a strict sesame-free diet, suggesting that cross-reactivity was probably responsible for the development of the new reactions after accidental exposure to sesame.

Finally, children who outgrow one allergy are not necessarily in the clear when it comes to their other allergies; one study has shown that sesame (and tree nut) allergies can exist or develop in children even if they do become tolerant to peanut, so outgrowing one type of allergy doesn’t mean that you can stop being vigilant when it comes to avoiding other nuts and seeds.

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Symptoms of sesame allergy

Sesame allergy can be IgE-mediated, non-IgE-mediated or mixed; a combination of both.

A 2021 review cclassified sesame allergy into 5 different subtypes that either manifest as immediate or delayed reactions.

Immediate reactions to sesame

Immediate allergic reactions are caused by IgE antibodies. These antibodies bind to certain immune system cells—mast cells and basophils—and trigger the release of histamine and other inflammatory chemicals that cause the characteristic symptoms of allergy.

Types 1 and 2: serious, immediate-type reactions in which symptoms can appear anywhere within minutes to 3 hours after eating sesame seeds (type 1) or sesame oil (type 2).

The symptoms involved include:

• Skin (cutaneous) symptoms: eczema (atopic dermatitis), hives (urticaria), swelling of the face (angio-oedema) and/or tongue and/or throat and/or hands, redness (erythema), itchy skin (pruritus), oral allergy syndrome (OAS, commonly manifesting as ‘itchy’ or ‘burning’ symptoms often limited to the mouth, sometimes also swollen lips and cheeks)
• Breathing (respiratory) symptoms: blocked nose (nasal congestion), runny nose (allergic rhinitis), wheezing, difficulty breathing/shortness of breath (dyspnoea), persistent cough, hoarse voice
• Digestive (GI) symptoms: nausea, diarrhoea, vomiting, stomach pain
• Cardiovascular symptoms: low blood pressure (hypotension), rapid heart rate (tachycardia), loss of consciousness (syncope)
• Neurological symptoms: headaches, dizziness, blurred vision, anxiety, confusion, seizures, fatigue and malaise (aka ‘a feeling of impending doom’, which can occur during anaphylactic reactions)

Symptoms typically appear within 10 to 60 minutes. These types of reactions can be very serious, even deadly.

According to a 2019 review, people who experience immediate reactions to sesame are more likely to have skin symptoms (71.6% had hives) and less likely to have gastrointestinal symptoms (8.3% experienced vomiting) than people who are allergic to the other major food allergens.

A recent Turkish study that looked at the medical records of 84 sesame-allergic children reported that skin/mucosal reactions were the most common initial reaction, affecting 85% of the 60 children for whom there was first reaction data, followed by gastrointestinal reactions (31.7%) and respiratory reactions (11.6%). The overwhelming majority of the children experienced mild to moderate reactions, with only 1.7% being classed as severe. During the follow-up period, however, around half of the children experienced anaphylaxis.

Respiratory symptoms are often work-related. There are 2 case reports of bakers who had asthmatic symptoms when they were at work, but not outside of work, one of whom also developed hives and hay fever symptoms.

And, in a work-adjacent example, there is also a case report of a 7-year-old girl who developed shortness of breath and wheezing whenever she visited her parents bakery and whenever they returned home, on days when they baked sesame bread.

A notable feature of sesame allergy is that it seems to provoke serious reactions in a relatively large proportion of sufferers.

In the UK, a sesame-focused survey of members of the Anaphylaxis Campaign found that 1 in 6 of the respondents had suffered potentially life-threatening symptoms, with almost two thirds of those reactions happening on the first known exposure to sesame.

According to data from the multicenter European Pronuts study, in which children were given food challenges with tree nuts, peanut and sesame seed, reactions to sesame seed generally involved the highest number of organ systems.

Research from the US has found that children with sesame seed allergy run a higher risk of suffering a severe reaction during an oral food challenge than children with other food allergies, especially those who are older and suffer from asthma, and adults with sesame see allergy run a higher risk of having to visit to a hospital’s emergency department than adults with allergies to other foods.

In the Middle East, where sesame is commonly eaten, sesame-induced anaphylaxis rates tend to be higher than elsewhere. An Israeli study carried out in 2002 found that just over a third of infants and young children experienced anaphylaxis as their first reaction to sesame, making sesame the second most common cause of anaphylaxis in Israeli children after cow’s milk.

In Saudi Arabia, sesame is the third most common trigger of food-induced anaphylaxis, and it’s one of the top three foods responsible for causing anaphylaxis in Iran. In the Lebanon, although sesame was not in the group of most important food allergens for either adults or children, anaphylaxis was the only symptom manifested by the people included in the study.

Similarly, a Canadian study that examined all of the cases of paediatric anaphylaxis to sesame registered in the Cross-Canada Anaphylaxis Registry between 2011 and 2021 found that anaphylaxis was the first reaction to sesame in around two-thirds (62.3%) of the 130 reported cases, with hummus accounting for over half the reactions. Sesame was also found to account for 4% of all food‐induced anaphylaxis in children.

In the US, the first reports of anaphylaxis to sesame appeared in the 1980s, with descriptions of people having severe reactions after eating a variety of sesame-containing products including halva candy, sesame oil in salad dressing, sesame flour and sesame seeded burger buns. One man reported experiencing swelling of his lips and tongue after putting one sesame seed on his tongue.

n Europe, sesame has been implicated in cases of anaphylaxis in France, Italy, Spain, Germany and the Netherlands, thanks to foods like sesame-containing bread and sweets and foods containing tahini.

In the UK, a sesame-focused survey of members of the Anaphylaxis Campaign found that 1 in 6 of the respondents had suffered potentially life-threatening symptoms, with almost two thirds of those reactions happening on the first known exposure to sesame.

Don’t panic: To be clear, the official definition of anaphylaxis is probably not what you think it is.

This means that many of the cases of anaphylaxis reported in medical studies are not actually life-threatening—when dealing with an emergency, however, since it’s impossible to predict which reactions will become life-threatening, every case of anaphylaxis should be treated as if it is potentially deadly, especially if the person having the reaction is asthmatic.

In the case of anaphylaxis to sesame, to date, although reactions are often quite serious, very few deaths have been reported. They include the death of 15-year-old Natasha Ednan-Laperouse, whose parents set up a foundation for allergy research in her name.

Delayed reactions to sesame

Delayed allergic reactions can occur hours or even days after exposure to an allergen, unlike IgE-mediated reactions that often happen within minutes. These reactions either involve diseases that rely on cell-mediated mechanisms (immune responses that do not rely on the production of IgE antibodies but instead involve the activation of T cells and macrophages which leads to inflammation and tissue damage) or by ‘mixed’ diseases that rely on both IgE- and cell-mediated mechanisms.

Type 3: this type of reaction involves mainly skin symptoms—allergic contact dermatitis—that occur a day or two after exposure to topical medicine containing sesame oil. It’s not life-threatening but, if the person doesn’t stop using the oil, the skin can become chronically inflamed.

Type 4: this type of reaction often manifests as vomiting and diarrhoea within 1 to 4 hours after eating sesame. The condition is known as acute food protein-induced enterocolitis syndrome (FPIES).

Food protein induced enterocolitis syndrome (FPIES) is a delayed reaction that affects the whole gastrointestinal (GI) tract. There are two main types of FPIES, chronic and acute.

Chronic FPIES is quite rare and occurs mostly in infants who eat the trigger food on a daily basis. It can be recognised by intermittent vomiting and diarrhoea and, occasionally, failure to thrive (which means that a child is not getting in enough calories to reach a similar weight and size to other children of the same age and sex). Cases of chronic FPIES in adults are vanishingly rare, but not unheard of.

Acute FPIES is by far the most common form. In children, symptoms often occur within 2 to 4 hours after eating the offending food and can include:

• vomiting
• pallor
• lethargy
• dehydration
• diarrhoea
• shock or hypotension (i.e. low blood pressure) which can manifest as dizziness, fainting or blurred vision (as well as pallor and lethargy)

Sometime children with chronic FPIES end up developing acute FPIES and this form of FPIES can, in turn, develop into an IgE-mediated form of allergy.

In adults, the typical symptoms of acute FPIES are not the same as those seen in children. They can also appear faster. They include:

• stomach pain and cramps
• diarrhoea
• vomiting
• dehydration
• transient weakness and shivering (possibly hypothermia)
• lethargy
• weight loss

People who experience severe symptoms of acute FPIES may have a longer-lasting form of the disease.

Type 5: regular consumption of sesame can provoke chronic inflammation of the oesophagus—a condition known as eosinophilic oesophagitis (EOE).

Eosinophilic oesophagitis (EoE) is characterised by symptoms including:

• food impaction; this is when food becoming stuck in the oesophagus which can lead to a sensation of squeezing in the chest, and can be accompanied by excessive salivation (unlike choking, a person can still breathe and talk, but they cannot eat or drink any more)
• difficulty swallowing (dysphagia)
• abdominal pain
• reflux (the flow of liquid back from the stomach into the oesophagus)
• vomiting
• heartburn (pyrosis)
• stomach pain
• food refusal

Symptoms are variable and often age-dependent. In infants, EoE tends to provoke general symptoms of oesophageal difficulties such as gagging, vomiting, feeding difficulties and weight loss, or so-called ‘failure to thrive’. Young and school-age children have symptoms that are indistinguishable from those associated with gastroesophageal reflux, such as abdominal pain, vomiting and an unpleasant taste in the back of the mouth that comes from regurgitating sour or bitter liquid. Older children and adults are more likely to have trouble swallowing and to get food lodged in their oesophagus (food impaction) and, less commonly, to suffer from heartburn.

Another type of (often) delayed symptom linked to sesame allergy is eczema,a chronically relapsing inflammatory condition that specifically affects the skin. Symptoms can occur up to 48 hours after eating a trigger food and they look like this.

According to a study of 84 Turkish children with sesame allergy, those who developed sesame-induced eczema had their first reaction, on average, about 2 years later (at the age of 3) than those who had immediate, IgE-mediated reactions (‘type 1’ reactions according to the classification used by the 2021 review that I have used to describe sesame symptoms).

Because symptoms can be severe, if you suspect that you’re allergic to sesame, it’s important that you see your GP/family doctor and get a referral to an allergy clinic for further testing.

Threshold for reactions

Tiny amounts of sesame are needed to provoke a reaction.

VITAL®, the Australian initiative for voluntary incidental trace allergen labelling, put out recalculated threshold doses for the ‘Big 14’ allergenic foods in 2020. Using a database containing datasets from studies carried out worldwide that used double-blind, placebo-controlled food challenges (DBPCFC), they calculated that the lowest threshold dose of protein that was needed to produce a reaction in 1% of the population allergic to sesame is 0.1 mg. (Note: in this case, the ‘population allergic to sesame’ is 40 people who were given a DBPCFC) This is one of the lowest eliciting doses of the main allergenic foods.

10.3 mg was the dose needed to produce a response in 10% of the test subjects, and 306 mg was the dose needed to provoke a reaction in half of the test subjects.

Note: we’re talking about milligrams of sesame protein. Since a sesame seed contains about 0.544 mg of sesame protein, not even one sesame seed is needed to provoke a reaction in the most sensitive of the sesame-allergic. (For comparison’s sake, a tablespoon of hummus contains about 500 mg of sesame protein, or at least 5000 times the dose needed to provoke the most sensitive of sesame allergy sufferers.)

A new and improved threshold dose calculation for sesame came out in 2022—now including 67 people undergoing a DBPCFC!—and put the amount of protein needed to provoke a reaction in 1% of the sesame-allergic at 0.2 mg, and the amount needed to provoke a reaction in 10% at 8.2 mg. That’s still a tiny number of sesame seeds.

Ultimately, the threshold dose needed to provoke symptoms varies widely between people. It also varies per person, depending on the circumstances around the meal.

Your threshold can be lowered and your allergic reactions worsened by things called ‘cofactors’. Cofactors include things like how much you eat and whether those ingredients have been cooked or processed, as well as exercise, anti-inflammatory drugs, alcohol, infection and stress.

Sesame has been specifically implicated in cases of food-dependent exercise-induced anaphylaxis (FDEIA).

Cofactors are thought to play a role in about 14% to 30% of all anaphylactic reactions.

Please note: the amount of sesame needed to provoke a reaction says nothing about how severe the reaction will be. And, even if your reactions have been mild in the past, that does not mean that they will continue to be mild.

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Diagnosing sesame allergy

A diagnosis of sesame allergy will primarily be based on your clinical history—a record of consistent symptoms following the consumption of sesame or sesame-containing foods. This will require you to provide your allergist with answers to questions about your general medical background (including any other allergies you may have and relevant illnesses in your family) and your dietary history (what you ate to provoke your symptoms, what those symptoms were, how long they lasted, whether you had exercised or taken painkillers and many other details).

Your medical history determines what comes next; on the basis of your answers, the allergist will try to determine what type of allergy you have—a primary, immediate-type allergy, a cross-reactive allergy or a delayed-type allergy—or whether it could be something else, and this will determine the tests they ask for to come up with a diagnosis.

Diagnosing IgE-mediated reactions to sesame

Skin tests

An IgE-mediated sensitisation to sesame is typically confirmed by a skin prick test, which involves someone placing a small sample of sesame extract onto your skin (generally the forearm of an adult/older child or the upper back of a young child) and pushing it through the top layer of skin by pricking it with a lancet. It takes about 15 minutes to see a reaction (or not).

This test is often carried out first because it is quick and simple to perform and gives rapid results, but it is generally used to rule out an allergy rather than to confirm one, because it has excellent negative predictive value—if the skin weal is under a certain size, you are highly unlikely to have an allergy—but poor positive predictive value—the skin weal has to be very large before an allergist can say with any kind of confidence that you probably have an allergy.

The diagnostic accuracy of a skin prick test using commercial sesame extract is not always reliable. This is partly explained by defatting procedures used during the production process that remove the oleosins from the extract. This means that someone who reacts to those specific allergens will get a false negative result and be wrongly told that they are not allergic to sesame.

One solution to this problem is the prick to prick test. This test is very similar to the skin prick test, except first the lancet is used to puncture fresh food—such as crushed sesame seeds, sesame seed flour extract or tahini sauce—and then it is used to prick your skin. When the food is in liquid form, the technique is actually the same as the one used for the skin prick test and, when the food is solid, it’s often ground down and put in saline solution.

It has a much better chance at diagnosing people who are actually sensitised to sesame and is much better at predicting the results of an oral food challenge and enabling someone who has the potential of suffering a severe reaction during one to avoid it.

Blood tests

Sometimes, the doctor may decide to order a blood test, aka an immunoassay. Perhaps the skin prick test was inconclusive, or the suspected allergen is not available for skin prick testing, or you’re unable to undergo the test for some reason.

A blood test involves having a small sample of blood drawn so that it can be sent to a lab where technicians will use allergen extracts to check whether there are IgE antibodies in your blood that react to them. It can take 1 or 2 weeks to get the results.

Blood tests can be less sensitive or specific than skin tests, but they have other advantages: they are perfect for people who cannot stop taking certain medications or have extensive skin disease or tattoos, and they can safely be used on infants, squirming toddlers and people who are at risk of suffering an anaphylactic reaction.

Blood test panels also typically include a whole range of potential allergen extracts including other foods or aeroallergens that the allergist may want to check your reaction to.

For more specific information, a component blood test—aka Component Resolved Diagnosis (CRD)—can be carried out. Instead of using extracts of whole foods containing only (heat-stable, plentiful) allergens, the CRD tests the reaction of IgE antibodies in your blood to isolated, individual proteins. This improves the diagnostic sensitivity of the test as allergens that would otherwise be missing from the whole food extract or exist only in tiny amounts are present in concentrated form in the CRD test.

This type of test enables the doctor to see exactly which allergen(s) you react to, which allows them to determine whether you are sensitised to cross-reactive allergens that are unlikely to produce symptoms, and whether you are sensitised to certain allergens that could affect your management plan. For example, if you’re sensitised to the Ses i 1 allergen, you may be at risk for severe allergic reactions.

Component blood tests are also made up of very large panels of allergens which include many other foods and aerollergens that the allergist may want to check your reaction to and can help to determine whether or not a sensitisation to a cross-reactive allergen will be symptomatic or not.

Unfortunately, although CRD could potentially reduce the need for oral food challenges and contribute to tailored management plans, it’s not yet considered a routine diagnostic method and it’s not comprehensive; the most widely used tests neither contain all of the identified allergens (which are also not all of the possible allergens), nor are they universally available. Testing for certain specific sesame allergens would require special preparation and is therefore only likely to be done for research purposes.

Additionally, as it is with skin and standard blood tests, CRD is better at confirming an allergy than at eliminating the possibility of one. And, because sensitisation patterns differ according to geography and populations, with different allergens being more important in different regions and in people of different ages, allergists need to understand their patient populations so that they interpret the results of the tests correctly.

Although a diagnosis of food allergy often follows a stepwise approach (first the clinical history, then the skin test, then the general blood test), because skin prick tests often show inconsistent results, some allergy specialists choose to do the skin prick test and blood tests looking for both sesame-specific IgE as well as the allergen Ses i 1 at the same time, to have a better chance of getting the diagnosis right.

When a patient has a history of anaphylaxis and a high probability of being allergic to sesame, the doctor may choose to avoid the skin prick test—which could cause a serious reaction—altogether in the hope that the blood test will provide the necessary answers (and possibly make a food challenge unnecessary).

That said, blood tests for sesame allergy don’t have the best performance record.

An American study found that skin test results were more accurate predictors of sesame allergy than blood test results. A Turkish study agreed, finding that both commercial extracts and tahini sauce were better predictor of allergic reactions during subsequent food challenges.

Canadian researchers who recruited children who were known to either have an allergy or be tolerant to sesame were unable to establish a meaningful threshold of sesame-specific IgE in the children’s blood that accurately determined their allergic status. They suggested that a blood test might be better used to exclude rather than diagnose sesame allergy because few children with sesame-specific IgE under a certain level did not react to sesame. Higher levels of IgE to sesame were less significant; more children with relatively high levels of sesame-specific IgE were able to eat sesame without having reactions. Those children all happened to be allergic to peanuts.

Their results were corroborated by an American study which also found that children with peanut allergies and high levels of sesame-specific IgE did not react when eating sesame. This is the result of cross-reactive sensitisation between sesame and peanut allergens confusing the issue.

You therefore won’t be surprised to learn that a positive skin or blood test does not mean that you are allergic to something. While lab tests do help with diagnosis, positive results only show sensitisation to specific allergens. Being sensitised to a food doesn’t mean that you’re allergic to it and that you will develop any symptoms.

For example, in one study, when 108 American children with positive skin or blood test results to sesame were given a food challenge, only 15 (12.6%) reacted and, in another study, of the 33 children who were sensitised to sesame, only 7 (21%) reacted after eating it. Similarly, a study of involving Iranian children also reported that, although 35 were sensitised to sesame, only 5 (14.3%) of them actually had allergic reactions when challenged.

A positive test result simply means that your immune system is aware of a specific allergen or allergens in that food. Why some people later develop an allergy to that food, and some do not, is not yet known.

Neither can the results of your blood or skin test predict how severe your reaction to eating some sesame might be. For the most part, the results of skin and blood tests have been shown to have no correlation with the results of oral food challenges.

Food challenge

The only way to get a definitive diagnosis of sesame allergy, and to have some idea of how severe your reactions may be and how much sesame is needed to provoke them, is to undergo an oral food challenge. This generally involves eating a very small amount of sesame, waiting for a reaction, and then doing it again, gradually increasing the dose until an objective—visible—reaction occurs or a maximum dosage is reached. It can take around 4 hours, depending on the type of challenge undertaken and the length of observation time needed.

You can read more about oral food challenges here.

Oral food challenges are normally carried out when someone’s history and their test results disagree (i.e. they have negative tests results—including both a skin prick test using commercial extracts and a prick to prick test using fresh food— but their history strongly suggests an allergy, or vice versa). They can also be carried out to check whether someone has outgrown their allergy to ensure that they don’t unnecessarily restrict their diet or worry about hidden allergens in processed foods.

Oral food challenges may be even more important for sesame-allergic adults than they are for children, according to a study which examined the medical records of 33 adults who had had an oral food challenge to sesame during a 6-year period at a hospital in London. The researchers compared the results of the food challenges with the results of skin prick and blood tests also undergone by the patients and found that, of the 10 adults who had reacted to sesame during their food challenge, 9 had had negative skin prick and blood test results and would have been wrongly told that they weren’t allergic to sesame if they had not undergone an oral challenge.

In fact, there are several reports of people who have anaphylactic attacks during sesame food challenges (including some of the adults in the previous study), even though they had negative skin and/or blood test results, probably because the sesame extracts being used for current testing are ‘deficient in clinically important allergens.’

Because of the risk of severe reactions, oral food challenges should only be done by an experienced consultant in a medical setting.

Practically speaking, most people do not undergo this kind of test since it requires a lot of time and resources. And oral challenges are rarely, if ever, offered to people whose history includes severe reactions to a suspected food. Whenever possible, allergy diagnoses are based on a combination of medical history and lab tests.

Although food challenges help to diagnose food allergies and identify a suspect food, there are other reasons to undergo food challenges, namely:

• to identify culprit foods in cases of allergies to multiple unknown foods
• to determine a patient’s threshold—how much sesame they can eat without reacting—so that dietary advice based on the outcome of the challenge can be given
• to confirm the development of tolerance to sesame

Other tests

Other tests are sometimes used to diagnose sesame allergy. For example, when respiratory symptoms are thought to occur due to the inhalation of allergens—for example, in a bakery—an inhalation challenge can be carried out. In the case of the little girl who developed shortness of breath and wheezing when she visited her parents bakery, her skin and blood tests produced such alarming results that an oral food challenge was considered too risky and instead, her diagnosis was confirmed by spirometry, a test which measures the airflow into and out of your lungs. In her case, her FEV (the amount of air she could force from her lungs in one second) was 21% less after she’d handled some seeds for 15 minutes.

Diagnosing non IgE-mediated and mixed reactions to sesame

Non IgE-mediated diseases are difficult to diagnose for several reasons, not least of which is the fact that IgE testing is often of no use. This makes the clinical history especially important for the diagnosis of these types of conditions. Even then, the symptoms are not easy to connect to the actual meals because of the time delay, and the symptoms associated with digestive allergies lack the skin and respiratory signs that doctors usually associate with allergy.

Skin tests

Eczema is diagnosed based on personal and family history of allergy and a skin examination.. While there are no standard diagnostic criteria, there are certain features that a doctor can look for to diagnose it.

That said, these criteria are based on the characteristics of paediatric eczema, which is not the same as the manifestation of eczema in adolescents or adults, making diagnosis of eczema in older age groups more challenging. Sometimes people with eczema in these age groups will have to undergo additional tests to rule out other diseases first, and a skin biopsy may be needed before a diagnosis of eczema is made. However, these differences are now being taken into account and guidelines are being updated.

Once the diagnosis of eczema is made, efforts will first be made to try and get the skin condition under control using topical skin creams and drugs before any further testing is done. Generally, only if the skin is not getting any better will tests be carried out to see whether allergens, like food, could be aggravating the condition.

The identification of potential food allergens is generally done by looking for specific IgE antibodies to a food using skin prick tests or blood tests (the latter is often used if the skin condition is too bad for a skin test, or medications are being taken that will interfere with the results, or if the tests involve a young infant).

In cases of delayed symptoms, doctors may use the atopy patch test (APT). This test generally involves walking around with food (either fresh or in solution) contained in tiny aluminium capsules taped to your back for up to 3 days and having your skin checked for a reaction after 48 hours and 72 hours.

The APT can also be used to diagnose cases of allergic contact dermatitis. In cases where contact dermatitis is the result of a suspected reaction to sesame oil in, for example, an ointment used to treat burns, a rapid (20-minute) contact test may be carried out, which involves applying a square of filter paper soaked in allergen to the underside of the forearm and checking for a reaction after 20 minutes,

Because sesame is generally not available in commercial APT kits, the test extract has to be made up specially, either using sesame oil in its natural state, or separate lignin components (sesamol, sesamin, and/or sesamolin).

The atopy patch test has also been used to try and diagnose delayed digestive allergies, with mixed results; in the case of food protein–induced enterocolitis syndrome (FPIES), for example, it has proven itself to be both ‘a promising diagnostic tool for the diagnosis of FPIES’ and ‘not helpful in identifying the [trigger] foods’, while showing ‘poor utility in the follow-up prediction of outgrowing FPIES in children’, and with eosinophilic oesophagitis (EoE), it has shown that it can ‘identify potential causative foods’. For these diseases, it is not the diagnostic instrument of choice.

A skin application food test (SAFT) may be used instead for children under the age of 4. It’s basically the same thing, but the capsule of food is only applied to the skin for 10 to 30 minutes. It’s had mixed results, having been described as reliable and child-friendly and also as not being as good as the APT in diagnosing certain food allergies.

Elimination diets and food challenges

While skin tests may provide an indication of sensitisation, they cannot diagnose a food allergy; that has to be done with a food challenge during which the doctor can see whether or not, in addition to any immediate reactions, the suspected food produces a worsening of the skin symptoms within the next 48 hours. If it does, the food can then be eliminated from a person’s diet and their skin condition will be monitored for the next few months to see if there is a persistent improvement. When more than one food is suspected, the next challenge will be done a few weeks after the first one.

The diagnosis of delayed digestive allergies generally starts with exclusion; first other possible causes of the symptoms are eliminated and only then will the suspected food(s) be excluded from a patient’s diet—and, if they are breastfeeding, from their mother’s diet, too.

If the symptoms disappear, the first step towards a diagnosis involves reintroducing the foods one by one into the diet and seeing if the symptoms return. If the symptoms don’t disappear, it could be that the diet has not been restricted enough or that other foods should (also) be considered for elimination. Or it could be that something other than an allergy is responsible, in which case, the allergist’s job ends and another specialist’s begins.

The diagnosis of food protein induced enterocolitis syndrome(FPIES) mainly relies on a person’s clinical history and symptoms appearing when the offending food is reintroduced after an elimination diet.

In the case of chronic FPIES, an elimination diet should result in the symptoms going away within 3 to 19 days. Reintroducing the trigger food should produce the symptoms of acute FPIES—i.e. projectile vomiting—which should be enough confirmation.

In the case of acute FPIES, eating the offending food should be followed by symptoms that should fit specific diagnostic criteria including copious vomiting within 4 hours. Although confirmation of the diagnosis officially requires an oral food challenge, because it often produces nasty symptoms that the patient quite rightly has no wish to suffer through, in practice, this is rarely done and challenges for the diagnosis of chronic FPIES are more common.

However, since FPIES symptoms tend to be different for adults with acute FPIES and there are no strict diagnosis guidelines for them, oral food challenges are often necessary.

There are other reasons to undergo food challenges in cases of FPIES, including:

• identifying a culprit food in cases of allergies to multiple foods
• confirming the development of tolerance to a trigger food, which is often done between 12 to 18 months after the most recent reaction

Although the majority of people with FPIES will have negative skin or blood tests to their trigger food, in some cases people do have an IgE sensitisation too. This is called ‘atypical FPIES’ and it affects between 1 in 4 and 1 in 8 people with FPIES. According to American research, the foods most commonly associated with this type of FPIES are egg, milk and peanut, but this may just be because those are the foods most typically eaten by American children (who make up the bulk of these studies). A person can have atypical FPIES to several foods, and those foods can include anything, from shrimp to avocado.

Some children with atypical FPIES may take longer to outgrow their condition (if, indeed, this happens at all) or may develop a classic IgE-mediated food allergy with potentially more dangerous symptoms. As such, periodic testing for an IgE sensitisation is advised in children who also have an IgE-mediated food allergy to other foods or suspected food-induced eczema.

When diagnosing eosinophilic oesophagitis (EoE), other conditions that produce similar symptoms, like gastroesophageal reflux disease (GERD), are first eliminated as a possibility before any intrusive testing is done. Then, if eosinophilic oesophagitis is still suspected, an upper GI endoscopy (aka an oesophagogastroduodenoscopy) and biopsies are carried out to look for specific levels of eosinophils in the oesophageal tissue (15 or more eosinophils per high-powered field, to be precise).

Standard elimination diets for cases of EoE are often based on the most common causes of the disease, either ‘2 food diets’ (dairy and wheat), ‘4 food diets’ (dairy, wheat, egg, and legumes) or ‘6 food diets’ (dairy, wheat, egg, legumes peanuts/tree nuts and fish/shellfish). These are called ‘empiric’ diets, i.e. diets that are based on observation and experience. The diet can be made less cumbersome by starting small, first with one food (i.e. milk) or two foods and then eliminating more foods if the symptoms don’t disappear.

The empiric diet approach is not the only approach. Sometimes the foods to be eliminated are determined using lab tests—atopy patch test and SPT and/or blood test—first (a targetted approach). Both methods work equally well for both children and adults although the targetted approach has the advantage of often requiring the elimination of fewer foods. That said, a lot of people with EoE don’t have any measurable IgE antibodies to their trigger food, so the targetted approach can only help some.

The diet normally takes about 6 weeks. If the symptoms go away and the tissue samples look good, the trigger is assumed to be one or more of the foods that was eliminated. In order to pinpoint the trigger(s), each food is reintroduced back into the diet one by one. If a reintroduced food causes symptoms to return and/or biopsy specimens to look abnormal, then it is identified as a trigger food and must be eliminated from the diet indefinitely. (In the real world, children may balk at undergoing so many intrusive tests or there may not be the capacity to perform them, in which case, they will probably not be required for a diagnosis.)

Elimination diets are best performed under expert guidance, because there is a risk that excluding a food from your diet because you think that you may be allergic to it or because it causes mild or delayed symptoms can lead to you developing an IgE-mediated allergy to that food, often with severe—sometimes fatal—reactions.

The good news is that, when a delayed digestive allergy is diagnosed, excluding offending food(s) from the diet leads to the resolution of symptomsand the repair of the underlying tissue damage in most children and adults, and improves quality of life, even though the diet may be difficult to stick to. When it comes to young children, if staple foods are being eliminated, dietary guidance may be needed to ensure normal growth and development.

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Good to know

People who are prone to allergies—atopic—run a higher risk of developing an allergy to sesame.

An atopic person is someone who is prone to develop an allergic reaction in response to a trigger. Studies have shown that the presence of other allergies is a risk factor for allergic reactions to food. This is no different when it comes to sesame allergy.

Several studies have found that the majority of people with an allergy to sesame are likely to have other allergies. For example, of the 1,394 sesame-allergic people in this study, 67% had hay fever, 73% had eczema and 94% were allergic to peanuts or tree nuts

And of the 362 sesame-allergic people in this study, 81.6% had at least 1 more convincing food allergy, and many had other allergies; 27.2% had asthma, 13.7% had eczema, 18.8% had an allergy to medication, 8.6% had an allergy to latex and 7.0% were allergic to insect stings. Additionally, compared to people with other common food allergies, those who were allergic to sesame were significantly more likely to have EoE and FPIES (3.6% and 4.4%, respectively, in this group of people)..

Sesame allergy has also been reported in combination with coeliac disease, and it may have a genetic component itself; a 2021 study carried out in an American health care centre reported a higher prevalence of sesame allergy among its patients with Middle Eastern or North African ancestry.

You can develop an allergy to sesame after an organ transplant.

Although it can happen after different types of transplant, the liver is by far the organ most likely to come with a new food allergy. When it comes to acquiring a new sesame allergy after a liver transplant, case reports currently only describe it happening to young children (and not very often—sesame is the 10^th most common food listed in a large review, after the other food major allergens and the categories of fruit and legumes).

Children are much more likely to develop an allergy after a liver transplant than adults; in fact, there are case reports describing children and adults getting a liver from the same donor and the child developing a food allergy while the adult does not. Why this is so is not known; it could be something about the liver itself, or the fact that the child needs a liver transplant in the first place, or it could be because a child’s immune system is too immature to be able to suppress the expression of newly acquired food allergies.

Symptoms of liver transplant-acquired food allergies (LTAFA) generally appear within 18 months of the operation—although it can take longer—and typically involve the skin; facial swelling (angio-oedema) and hives (urticaria) occur in around 4 to 5 in 10 people. Gastrointestinal manifestations (diarrhoea, vomiting, stomach pain) also affect around half of people with LTAFA, while respiratory symptoms affect about 1 in 10. Anaphylaxis affects around 16 in 100 children with LTAFA, but no fatal cases have been reported so far. Although the majority (around 4 in 5) of the new food allergies are IgE-mediated, some people also get mixed or non-IgE-mediated allergies like Eosinophilic Gastrointestinal Disorders (EGIDs).

Unfortunately, once you develop this type of allergy, you’re likely to keep it, with only about 1 in 4 people becoming tolerant to their food trigger(s).

Introducing your child to sesame seeds and/or peanuts during early childhood may help to prevent the development of sesame allergy.

A 2008 study examining the prevalence of peanut allergy among Israeli and British Jewish children revealed that the prevalence of peanut, tree nut and sesame seed allergy was lower among the Israeli children than it was among the London-born children, with the major difference between both groups being that Israeli children started consuming peanuts at a much earlier age than their English counterparts; indeed, this is the study that kicked off the research that resulted in the guidelines recommending the early introduction of peanut into children’s diets to avoid peanut allergy.

More pertinently, the researchers also noted that the greater prevalence of sesame allergy in the English children (0.79% vs 0.13% in the Israeli children) might be due to the fact that Israeli infants also ate more sesame than British infants. Another possibility was that the lower prevalence of sesame allergy among the Israeli children was a positive side-effect of their ‘early, high, and frequent consumption of peanut’ which could be inducing ‘cross-tolerance’, thanks to the homologous allergens in the two foods.

Additionally, the more recent European Pronuts study noted that no children in Valencia had sesame allergy, which the researchers noted ‘might be explained by the high rate (93%) of children already eating sesame seed before study entry’—i.e. most of the children were introduced to sesame as soon as it was age-appropriate.

If you have an infant who is at high risk of developing food allergies and you are interested in seeing whether early introduction to sesame and/or peanuts might also help them to avoid developing sesame allergy, consult your allergist about it first.

A permanent solution for sesame allergy is being worked on.

Scientists are hard at work on a long-term solution for sesame allergy involving oral immunotherapy (OIT). A 2014 study ffound that sesame OIT was safe and successful when included with other foods to treat people with multiple food allergies.

A study carried out on 60 Israeli patients in 2019 fully desensitised 53 (88%) of them. 4 more were able to tolerate over 1000mg of sesame protein by the end of treatment, meaning that the therapy made a noticeable and positive difference for 95% of the patients.

Another case the same year described the successful treatment of a Brazilian woman with a history of several episodes of anaphylaxis after eating sesame. She was treated with a white sesame extract and then tahini and, by the end of the treatment, she no longer experienced any symptoms when she ate sesame.

Recent research has shown that OIT in combination with omalizumab can successfully treat adults with severe sesame allergy. In a 2022 study, 11 Iranian adults who suffered from sesame anaphylaxis underwent OIT while using omalizumab (an injectable medicine that treats allergy symptoms). After 4 months, they were all able to eat at least 22g of tahini without symptoms. The safe and successful completion of the immunotherapy treatment with these sensitive patients was put down to the use of omalizumab, which made the symptoms tolerable and the therapy therefore possible; no patient, despite a history of severy anaphylacti reactions, had an anaphylactic reaction during treatment and all patients were able to reach the target dose of sesame.

Recent research has also shown that sesame OIT is a safe and efficient treatment for young children. In 2024, a Canadian team published the results of a study examining the safety and efficacy of treating sesame-allergic preschoolers (aged between 9 months and 5 years old) with low dose immunotherapy using tahini. Low dose therapy was suggested because a lot of children just don’t like tahini and don’t want to eat the required amount. 23 children started the therapy and 21 completed it, successfully keeping up with 1 year of 200g daily maintenance doses (about a sixth of the amount used in other studies) as required. Of those 21 children, 18 were able to tolerate the final 2000 mg target dose (chosen because it’s an age-appropriate serving size).

At this time, there are no commercially available products for sesame immunotherapy and treatment is generally not routinely offered to patients. However, if you are interested, it certainly wouldn’t harm to ask your doctor if they know of any clinical trials available near you or of any allergy clinics that may be able to help; some private clinics, such as the New England Food Allergy Treatment Center in the US have reported successfully desensitising several patients to sesame.

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