The Food Standards Agency estimates that 1-2% of the UK population have a food allergy. Symptoms of a food allergy are stomach cramps, vomiting, abdominal pain and difficulty swallowing, swollen lips, fingers, ears and mouth, patches of itchy skin and sore rashes. Some allergic reactions are mild, but others can be life threatening – for example anaphylaxis which causes breathing difficulties and extreme swelling. Food allergy symptoms will usually appear soon after eating or coming into contact with the food (within 2 hours). The most common food allergens are peanuts, tree nuts (such as almonds and Brazil nuts), eggs, milk, fish, shellfish, and sesame.
Food intolerances are different from allergies in that the immune system is not involved. Intolerances commonly occur when the body does not produce enough of an enzyme or other substance needed to digest a food. Symptoms can include stomach pains, bloating, fatigue, diarrhoea, night sweats and skin disorders.
Common food intolerances include lactose, gluten, salicylates and food additives. There can be different levels of intolerance – so some people can tolerate the food in small amounts and only experience symptoms when eaten in large quantities.
Unfortunately, food intolerances can be difficult to test. In fact, apart from coeliac disease and lactose intolerance, there aren’t any reliable and validated tests to identify food intolerance. This is why misdiagnosis can often occur.
What to do if you suspect a food allergy or intolerance
Food allergies tend to cause severe reactions so it’s essential to get these checked out immediately – your doctor will be able to perform simple tests involving using a very small amount of the suspected food allergen to stimulate a reaction. If you suspect an intolerance, the best way to test it is to keep a very clear food and symptoms diary alongside an elimination diet – remove the suspected food from your diet and then gradually reintroduce them into your diet, keeping note of your symptoms. It’s best to do this with the support of a registered dietician.
Having a food allergy or intolerance can be life-changing, and it’s essential for your health to get the correct diagnosis. For more information and support, contact Food Allergy UK.
Written by Ruth Tongue