The Difference Between an Allergy and an Intolerance

Two words which are often used interchangeably in society, and sadly sometimes in the nutrition world, are allergy and intolerance.  In actual fact, they have very different meanings, and the difference between the two can make a big difference to someone’s lifestyle and overall health.

So what is the difference?

The main difference between an allergy and an intolerance is that an allergy involves the immune system, and an intolerance does not. Symptom onset from an allergy is usually rapid (seconds to a couple of hours) whereas symptom onset from an intolerance usually takes hours to days. If you’re allergic to something, it normally means your body is allergic to a specific protein within that food. A common example you’ve likely heard of is gluten, the protein normally found in products such as bread, pasta, etc. This allergy is more commonly known as coeliac disease and is the reason why many people adopt a gluten-free diet. Another example commonly mistaken for lactose intolerance, due to the fact that they share many symptoms, is a dairy allergy. If someone is allergic to dairy it means they’re allergic to a protein found within the dairy, usually casein, and consuming such can potentially have some very severe reactions depending upon the degree of the allergy. The symptoms can include vomiting, diarrhoea, skin rashes, swelling of the face and anaphylaxis.

 So how is that different to an intolerance?

If you’re intolerant to something, it normally means that your gut simply cannot handle large quantities of a specific nutrient. Therefore it’s likely that you can continue to consume the nutrient, just in lower quantities. For example someone may believe they’re allergic to gluten, when they may actually have an Intolerance to fructans , a type of fibre within the food. Fructans can ferment in the large intestine, drawing in water and gas, causing symptoms such as abdominal discomfort, bloating and flatulence.

What does this mean for me?

Unless you’ve been told by a medical professional that you are specifically allergic or intolerant to a food, then don’t completely rule it out as you may be limiting your body from valuable nutrients, and maybe even some amazing flavours. If you are concerned that you may have an allergy or intolerance to something then please contact your GP or book an appointment with a registered nutritionist.