There seems to be a fad at the moment for people diagnosing themselves as having food allergies. But how do you know if you’re suffering from an allergy or just an intolerance?
When it comes to food allergies, the simple fact is that genuine allergies are actually quite rare. Various surveys have shown that around 20-30 per cent of people claim to have a food allergy, but it’s estimated that only one or two in 100 people actually do. Some of the confusion may arise from the fact that people often confuse a food intolerance – which may affect up to 45 per cent of the population – with an allergy.
The most common food allergies among adults are usually connected to peanuts, tree nuts, fish and shellfish, such as crab, lobster and prawns. Kids’ allergies are usually to milk, eggs, wheat, peanuts and fish. Many children will, however, grow out of these allergies by school age.
So how do you differentiate between an allergy and an intolerance?
Well, basically put, if you have an allergy to a food, you’ll experience symptoms such as hives, itchiness and swelling. These tend to flare up very quickly after you eat a particular food; usually within a few minutes. While these can be distressing, in severe cases they can cause anaphylaxis, which is potentially fatal. If you eat a food, for example, and begin to experience breathing difficulties, it’s vital that you get medical help immediately.
With intolerance, however, you’re more likely to experience longer lasting symptoms, which mainly affect the digestive system, such as diarrhoea, gas, bloating and stomach pain.
With food intolerance, the first thing to realise is that it’s not life-threatening! It’s simply a matter of working out which food is causing the symptoms, which are usually stomach pain and diarrhoea. One of the best ways of working this out is by going on an exclusion diet, where you cut out all possible culprits and then re-introduce one food at a time. When your symptoms reappear, then you’ll know which food is to blame. It goes without saying that food intolerance’s are difficult to diagnose, but with a bit of perseverance, you should be able to work out which foods to avoid.
If, on the other hand, you’re concerned that you have a food allergy, the first step is to go to your GP, who will probably refer you to a specialist allergy clinic. The most commonly used test is the skin prick test and a blood test called a specific IgE blood test, which checks for an antibody called immune globulin E or IgE, which is produced in an allergic reaction.
This test involves mixing the suspect food with liquid to make a solution. A drop of this solution is then placed on your skin. The skin beneath each drop is pricked with a needle and, if there is a reaction, such as swelling or if the skin becomes red and itchy, then the test is classed as positive.
If you test positive for an allergy to a particular food, then medications such as antihistamines are usually used. If your allergy is severe, however, you may need an adrenaline injection.