The soya bean belongs to the legume family, which includes fresh and dried peas, beans, carob, liquorice and peanut. Research has shown that a symptomatic reaction to more than one member of the legume family is rare. It is therefore in most cases not necessary to avoid all foods from this plant family.
Soya is widely used in foods and is difficult to avoid. As many as 60% of manufactured foods contain soya. Soya can be ingested as whole beans, soya flour, soya sauce or soya oil. Soya can also be used in foods as a texturiser (texturised vegetable protein), emulsifier (soya lecithin) or protein filler. Soya flour is widely used in foods including; breads, cakes, processed foods (ready meals, burgers and sausages) and baby foods.
Clearly, avoidance of all these products containing soya would make the diet very restricted. However, as with many other allergies, the level of avoidance required will depend on each individual case. Some people may need to avoid all these forms of soya, whereas others may be able to tolerate, for example, soy sauce and soya lecithin. In fact, most soy sauces contain very small amounts of soy, with most of the protein in the sauce being derived from fermented wheat.
Soya-derived lecithin is an emulsifier – it is a lipid (fat) which stabilizes foods which contain water and fats, which do not normally mix (which is why you have to shake many salad dressings as they contain oil and water/vinegar which do not mix). For example, lecithin stops the cocoa and cocoa butter in chocolate bars from separating. In addition, lecithin improves the texture of many foods such as chocolate and spreads, and also helps preserves some foods. Since lecithin is a fat, soya lecithin contains very little soya protein, and most people with soya allergy can tolerate it.
In the UK, the Food Standards Agency advises that refined soya oil (the main component of vegetable oil) should be safe for people with soya allergy, because the proteins that cause allergic reactions are removed during the refining process. However, cold-pressed soya oil, usually sold from delicatessen counters or health food shops, can contain soya protein and should be avoided.
Under government legislation, soya is classed as a major food allergen, and must therefore be clearly identified on all food ingredient labels of pre-packed foods for sale within the EU. Remember foods sold outside the EU (whether made within the EU or not), do not have to comply with these laws. Other foods that are not labelled because they are sold loose include delicatessen, bakery and butchers products.
When buying food or eating away from home, look out for the following:
(even if there is an allergen advice panel, always read the ingredients list in case of omissions)
- Soya protein isolate
- Soya shortening
- Soya protein
- Soya albumin
- Soya bean
- Soya flavouring
- Soya flour
- Soya gum
- Soya lecithin (E322)
- Soya milk
- Soya nuts
- Soya oil
- Soya starch
- Vegetable broth
- Vegetable oil
- Vegetable protein
- Vegetable paste
- Textured vegetable protein (TVP)
- Hydrolysed Vegetable Protein (HVP)
- Hydrolysed Plant Proteins (HPP)
This is a very extensive list, so finding out your level of avoidance is essential so that your diet is not more restricted than it needs to be.
Below is a list of manufactured foods, which either contains or may contain soya. Check the labels for any of the above ingredients. The list is not exhaustive, and this information is designed to give guidance on food choices.
- Soya infant formula
- Soya margarine
- Soya sauce
- Soya yoghurts and desserts
- Baby foods
- Breakfast cereals
- Cakes and biscuits (confectionery with a biscuit base)
- Cheese substitutes
- Canned and tinned soup
- Chinese foods
- Chocolates (especially those with cream centres)
- Commercial fruit products
- Dessert mixes
- Flavoured crisps
- Frozen dessert
- Ice cream
- Liquid meal replacers
- Meat products: cold cuts, beef burgers, meat paste/pies, minced beef, sausages, and hotdogs
- Milk (coffee whiteners) or cream replacers
- Pancake and waffle mixes
- Pasta/pizza bases
- Ready - meals (convenience meals)
- Sauces (including Worcester sauce, sweet and sour sauce, Teriyaki sauce, stock cubes, gravy powders and some cook-in sauces)
- Seasoned salt
- Snack bars
- Soups (canned or packet)
- Sandwich spread/mayonnaise/salad creams
- Vegetable products / vegetarian meals
Most supermarkets and many manufacturers produce lists of their food items, which are soya free. However, do be careful as these lists quickly go out of date and food products often change their ingredients. These lists however are a very useful guide to identifying potentially suitable products which can add taste, variety and nutrition to your diet.
Last updated: March 2012