ASDA Health Matters

What is wheat allergy?

Wheat contains lots and lots of proteins. Allergic reactions are caused by one or more of these proteins. So, ‘wheat allergy' is really a blanket term to cover all allergenic (allergy-causing) proteins. Usually the seed storage proteins are responsible - and there are four categories:

• Albumins
• Globulins
• Prolamins (gluten)
• Glutelins (gluten)

You'll notice that gluten, the protein which causes coeliac disease, has been mentioned. This is to make the distinction between coeliac disease and wheat allergy. Coeliac disease is triggered by the two gluten groups, whereas wheat allergy is the effect of any of the groups.

How is wheat allergy different from coeliac disease?

Wheat allergy and coeliac disease both involve the immune system but what makes them distinct is that different immune cells and antibodies are involved. In coeliac disease, immune cells attack each other, resulting in damage to the small intestine. In wheat allergy, the immune system responds by producing antibodies, called IgE, when the food is eaten; these enter the bloodstream and cause unpleasant or nasty reactions.

Wheat allergy is also different from wheat intolerance, which is when the body has difficulty breaking down one or several components of wheat.

How common is wheat allergy?

The number of people who have true wheat allergy, where IgE antibodies are produced, is unknown, but it's believed to affect a tiny percentage of the population. Most of these are children who outgrow their sensitivity in their early years.

You are what you eat?

A common phrase ... but one which may not be true if you have a wheat allergy! The allergens in wheat exist not only in the seed storage proteins (which are eaten), but in their pollen and grasses too. This means that respiratory allergies, such as rhinitis (hayfever, sneezing, runny nose and congestion) and asthma (known as ‘Baker's asthma'), can develop after inhalation of wheat pollens and grasses.

So, should I simply avoid wheat?

Some of the storage proteins in wheat are similar to those in other cereals such as barley, rye and oats, and therefore you may react to these cereals too. The proteins in wheat and rye are believed to have the greatest similarity. This is known as cross-reactivity.

Symptoms

Common symptoms typically affect the skin, gut and respiratory tract, for example:

• Skin - eczema, itchy skin, rashes, swelling
• Gut - stomach pain, sickness
• Respiratory tract - hay fever, asthma

These symptoms are mostly seen in children, who usually outgrow their sensitivity. Wheat allergy rarely occurs in adults but, when is does, it can be in the form of an anaphylactic shock, where tissue swelling, a drop in blood pressure and difficulty breathing mean that medical attention is needed immediately.

Diagnosis

Diagnosis of food allergies is usually by a ‘Skin Prick Test' (SPT), where a small amount of the suspected allergen is placed on the back or forearm and then a tiny prick is made in the skin, allowing the allergen to enter. A small rash (weal) forms within 15 minutes if the test is positive. Those who suffer from skin conditions usually have a blood sample taken instead.

An ‘Oral food challenge', which means avoiding the suspected allergen-containing foods and then gradually re-introducing them when symptoms disappear, can be the only option in cases where the SPT fails to identify an allergy. This method of diagnosis must not be undertaken without medical supervision - make sure you consult your GP before eliminating any food groups from your diet, in order to avoid nutritional deficiencies.

If I can't eat wheat, what do I eat?

Starchy carbohydrate, other than wheat, is found in more foods than you might ever have imagined. The obvious sources in the UK are potatoes and oats, but what does the rest of the world eat, where wheat is neither grown, nor forms part of the diet? Examples, which are increasingly available in the UK, include:

• Maize (corn) and cornflour
• Quinoa
• Millet
• Yams, sweet potatoes
• Polenta
• Rice and rice flour
• Barley*
• Rye*
• Buckwheat (not related to wheat)
• Spelt*
• Chickpea (gram) flour
• Potato flour

*If you are gluten-sensitive, these cereals may not be a suitable substitute

Some fruit and vegetables, such as plantains and parsnips, are also rich in starch, and are good sources of fibre too!

These alternatives to wheat can easily be incorporated into your everyday recipes; for example, quinoa and polenta can be used instead of pasta and for a quick lunch, why not try a filled baked potato instead of a sandwich? Rice, chickpea (gram) and potato flours are good alternatives to use when baking.

If cooking is not your forte and you simply want convenience, then wheat-free substitutes are available, such as bread, pasta, flour and biscuits; these can be bought in most supermarkets and health food stores. Unfortunately, they tend to be more expensive than standard products and are not normally available on prescription for those with wheat allergy. If you do want to buy them, make sure they are labelled ‘wheat-free' and not just ‘gluten-free'. Look for a ‘wheat-free' symbol and then check the ingredients list, especially on items which don't display the symbol. Wheat can be "hidden" in many processed foods; below are some popular ones:

• Gravy, gravy granules, stocks, cooking sauces
• Soups
• Bread and batter coatings; for example, fish fingers, crispy pancakes, Scotch eggs
• Sausages, burgers, processed meats
• Baked beans
• Ready-made desserts, biscuits and confectionery
• Powdered drinks, beers, wines and spirits
• Medication

And these are some of the items you may find in the ingredients list - all disguising forms of wheat....

• Maltodextrin
• Gelatinised starch, modified starch, vegetable starch, edible starch
• Natural flavouring
• Soy sauce
• Hoisin sauce
• Beta-glucan
• Bran
• Spelt
• Kamut
• Couscous
• Semolina

This list is not complete - there are many, many other forms of wheat, so the simplest way to avoid reactions is to choose naturally wheat-free foods. This is a good way to have fun in the kitchen and create your own meals - improving your nutritional status and overall wellbeing!

Raising your child on a wheat-free diet

If your child suffers from immediate and severe allergic reactions, the only way to avoid these is to exclude wheat from the diet completely. But if symptoms are mild and, possibly delayed, relief may be obtained by simply reducing the amount of wheat. Advice should always be sought from your GP.

If dietary adjustments do need to be made, teach your child to identify foods containing wheat, as soon as they are old enough to understand, and instruct them not to swap foods with their friends. You'll also need to explain your child's allergy to the headteacher, so that school kitchen staff can be informed of foods not to be eaten, as well as providing instructions of what to do if your child has a reaction. The same applies to anyone who looks after your child, such as after-school club leaders and parents of your child's friends.

And a final word of warning .... wheat can be hidden in childhood products, such as playdough and the stuffing of soft toys. This may not be identified on a label, but being aware of these potential suspects will help prevent future reactions if symptoms do occur after playing with these products.