Which foods are most likely to trigger an allergy?

• Cow’s milk
• Peanuts
• Other nuts
• Eggs
• Soya
• Wheat

Other relatively common foods for children to be allergic to include:

• Fish
• Shellfish
• Certain fruits (particularly citrus, strawberries and kiwi)
• Tomatoes

The symptoms of reactions to these foods can vary from mild stomach pains or skin rashes, particularly around the mouth, to immediate and severe anaphylactic reactions – although these are rare.

Cross-reactions

Sometimes, being allergic to one food can make a child more likely to react to other foods. This is known as ‘allergic cross-reaction’ and can happen because different foods contain the same allergen, or contain an allergen with a similar chemical structure.

For example, if someone is allergic to peanuts, they might also react to other beans such as soya, peas, lentils and pulses. And most babies with cow’s milk allergy are also likely to react to goat’s milk and sheep’s milk, because some of the proteins in these types of milk are similar to those found in cow’s milk.

Avoiding trigger foods

It can be difficult to make sure that your child avoids the foods that trigger his allergy. However, in the UK every ingredient in a food must be listed on the packaging, and there are laws that require food manufacturers to state on the label whether a food contains common allergens, such as eggs or nuts.

Sometimes ingredients can be ‘hidden’ by appearing under another name. For example, egg may be listed as albumen, while peanuts could be referred to by names like earthnuts or ground nuts. So, if your child has a reaction to a food that you thought was safe, it’s worth double-checking exactly what was the ingredients were, and familiarising yourself with alternative names for the ingredients that trigger his reaction.

Supermarkets and major food manufacturers publish regularly updated ‘free from’ lists to help you identify safe foods for your child. You can get hold of these lists free of charge by contacting the head office of your supermarket or the customer services department of food manufacturers.