28 Sep 2016

Differences Between Food Allergies & Intolerances

Nutrition Advice

Some of us have digestive systems that just can’t handle certain types, and we shouldn’t really eat them.

So what are the signs of food intolerance, and what can you do about them?

Food allergy vs. food intolerance

First up, it’s worth mentioning that food allergies can be life threatening and the symptoms are quite different (including vomiting, anaphylaxis and dizziness). They usually occur suddenly, small amounts of food can trigger them, and they happen every time you eat that food. Food intolerances surface gradually and may only happen when you eat (normally a decent amount of) certain types of food.

Food intolerance - symptomatic symptoms

Brain fog, headaches and moodiness

Gluten and sugar are natural opiates containing morphine-like substances metabolised from foods that contain wheat or dairy. If you’ve taken a break from them and get the ‘cranks’, it could indicate signs of withdrawal and, therefore, intolerance.


When you’re sensitive to a food, it doesn’t digest well and therefore tiny bits permeate your gut and enter your circulation. Antibodies rush to the scene as an immune response, but your body mistakenly anticipates another ‘attack’ and creates a truckload of them. When you’ve got too many antibodies and nothing to break down, they crave that food. And so do you.


If you’re intolerant to a food, your inflammation and immune responses are activated. This is because you’re not digesting properly and your body is working overtime to eliminate it, which leads to fatigue.


The classic cause is a low level of stomach acid and drinking too much liquid with meals makes it worse because you’re not breaking down certain foods properly. Chew well, monitor fluids and don’t eat just before bedtime.

Joint pain

This is the most common system and is due to inflammatory responses caused by genetically modified foods, antibiotics and pesticides (often in dairy, soy and gluten) and immune complexes unfortunately prefer to settle in joints.

Acne, rosacea and eczema

When you’re intolerant, sometimes your immune system speaks through your skin. Experts see a particular connection between dairy and acne or rosacea and again, recommend going without certain foods and noting any improvements.

Gas, bloating and constipation

Research suggests that the composition of your gut may be altered by diets high in processed food and these unpleasant side affects are the result.

Test yourself

There are no tests that can definitively diagnose a food intolerance, however, keeping a food diary can help you isolate what might be aggravating the symptoms. Avoid the food for 10 days and then consume it again. If you’re symptoms reappear, you’re probably intolerant to it. Alternatively, see your GP who will probably order a blood or skin test (to confirm allergies) or if warranted, a gastroscopy to check things out further.

Want to learn more about healthy eating? Study the 10967NAT Diploma of Nutrition with the Australian Institute of Personal Trainers. Call 1300 616 180 today.

Get in touch with AIPT today.

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