Do I have a food intolerance? | Lifelab Testing

How do I know if I have a food intolerance?

Last Updated: 12th January 2023 · Written by Donna Mastriani

Before you commit to a food intolerance test you’re probably wondering what you should be looking for that might indicate a potential food intolerance. Different food intolerances manifest themselves differently in one person than they may in another. But, there are a group of symptoms that are generally recognised as associated with a potential food intolerance.

Here we take a look at some common symptoms and the intolerance they could be indicative of.


Bloating is caused by the excess production of gas during the digestive process. When you have a food intolerance, your body struggles to digest the problematic food which slows down the process. As a result, the enzymes spend more time breaking down the food which means more time spent producing gases. These gases then become trapped in the stomach leading to uncomfortable bloating. You may find that you experience bloating whenever you eat a certain meal or food. If this is the case, it is very likely you’re living with a food intolerance.

Intolerances that cause bloating: gluten, milk, eggs.

Brain Fog

Brain fog is the experience of fatigue and an inability to focus on tasks for any period of time. This condition can be debilitating if left untreated and can have a serious impact on all aspects of life. Brain fog can be caused by a number of different factors including the foods you eat. When you sleep, your brain takes this opportunity to recover from the oxidative stress experienced throughout the day. To do this, it requires a good flow of oxygen. When you have a food intolerance, your nasal passages can become inflamed and restricted. This prevents a sufficient amount of air getting into your lungs and oxygen into your blood. When your brain doesn’t get the oxygen it needs, it can’t fully recover. This can leave you in a near constant state of fatigue known as brain fog.

Intolerances that cause brain fog: wheat, lactose, fructose.


Unsurprisingly, when your body realises you have eaten a food to which you’re intolerant, it tries to evacuate that food from your system as soon as possible. This means the normal digestive process simply won’t cut it. In an effort to expedite the process, your body will draw water into your bowels which combines with the food to create more fluid-like faecal matter. This aids its progress through the digestive system resulting in a near-immediate excretion. Diarrhoea can have significant negative health impacts, the water drawn from the cells to make the diarrhoea can leave you dehydrated and  causes an electrolyte imbalance. It is vital to identify any food intolerance that might be causing you to have regular bouts of diarrhoea.

Intolerances that cause diarrhoea: peanut, dairy, wheat.

How a Food Intolerance Test can help

Being aware of food intolerances is absolutely essential to maintain good health. When you know which foods you need to avoid, you’re able to plan your diet to avoid the symptoms above as well as other symptoms such as NAUSEA, HEADACHES, RASHES & OTHERS. You can find our range of intolerance tests, suitable to all budgets, here.

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