A reaction to a croissant, a gluten-free pasta or a vegan burger, with no obvious culprit on the plate? Lupin flour is used more and more in baking and plant-based foods, and it is one of the 14 allergens that must be labelled in the EU. Our test checks your blood for IgE to whole lupin seed, as part of 300 allergens and allergen components, with peanut and soy on the same report.
Lupin is a legume, a relative of peanut, soy, peas and lentils. Some lab panels file it under cereals because the flour is used like grain flour, but botanically it is a bean. Its seeds are rich in storage proteins called conglutins, which are heat-stable and survive baking.
Those storage proteins look like the ones in peanut. That is why lupin and peanut so often appear together in results. Reviews put lupin sensitisation at roughly 15 to 20 percent of people with a known peanut allergy, and the main shared protein in one study was beta-conglutin.
Reactions people describe after lupin include itching in the mouth, hives, swollen lips, stomach cramps, vomiting and wheezing. They usually start within minutes to two hours. Because lupin flour is mixed into everyday bakery products, many people do not realise they have eaten it.
People who handle lupin flour at work can also become sensitised by breathing in the dust.
Swelling of the lips, tongue or throat, trouble breathing or feeling faint after eating is an emergency. Call 112 (EU) or your local emergency number. Do not wait for a test.
Many people with IgE to lupin eat it without any problem, especially people sensitised to peanut, where the antibodies may recognise the similar lupin proteins without causing symptoms.
So a positive lupin result shows sensitisation. It does not tell you that you will react. If you have never reacted to lupin, do not change your diet on a result alone. If you have reacted, or if you have a peanut allergy and are unsure about lupin, take the result to a doctor or allergist.
The lab measures IgE to one whole lupin seed extract, which covers the full mix of lupin proteins rather than single components. Your lab report gives it a measured value and class, from Negative to Very high, on the same report as eight single peanut proteins and four soy proteins.
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One finger-prick sample checks IgE to 300 allergens and allergen components, from birch and peanut to cat and house dust mite. Post it to the lab, and about 5 days after it arrives you get a value for every one. Our plain-English guide shows you how to read them. €399 in total, €1.33 per allergen.
Yes. Both are legumes with similar storage proteins. Some people with peanut allergy also react to lupin, while many only show antibodies. Our test shows lupin and eight peanut proteins in the same report, so a doctor can look at both.
Lupin flour turns up in bread, pastries, pizza dough, gluten-free and high-protein products, and vegan meat and dairy alternatives. Lupini beans are eaten as a snack. In the EU, lupin must be named and highlighted in the ingredient list.
A legume. Its flour is used like grain flour, so some lab panels list it with cereals, but botanically lupin sits with peanut, soy, peas and beans.
