What are the symptoms of a food intolerance?

What are the symptoms of a food intolerance?

The food standards agency estimates that over 2 million people in the UK have been diagnosed with food hypersensitivity, which includes food intolerance and allergies.

A Food intolerance can occur when the body has difficulty digesting certain foods and ingredients. The prevalence of food intolerance seems to be accelerating, with a significant portion of the population now being affected.

Spotting the signs and symptoms of a food intolerance are essential when trying to determine what is a normal, common symptom and what is considered to be a serious reaction to food or the signs of an underlying condition.

In this guide, we will be looking at all things related to food intolerance symptoms.

Our guide details everything you need to know about a food intolerance.

Food intolerance symptoms

Food intolerances can have several symptoms, the severity and combinations of symptoms can vary throughout individuals, with some experiencing multiple symptoms at once.

The most common symptoms of a food intolerance:

  1. Bloating: Bloating is the feeling of fullness after eating, it is the result of having a lot of gas in your gut which can lead to flatulence (farting) and belching
  2. Gas: Excessive gas can contribute to bloating, you may also experience other symptoms along with this such as stomach ache
  3. Stomach Pain: Stomach pain and cramps in the abdominal region
  4. Diarrhoea: Postprandial Diarrhoea can cause loose and watery bowel movements within 30 minutes to 2 hours after eating
  5. Nausea: Feeling sick after eating, problematic foods can trigger this symptom more than others
  6. Indigestion: Discomfort, heartburn, or feeling overly full after eating, this can also cause stomach pain
  7. Tiredness and fatigue: Whilst feeling tired after eating can be normal, due to the body diverting energy to the digestion process, this can also be caused by a spike and drop in blood sugar levels

Symptoms to look out for

Uncommon symptoms of a food intolerance include:

  • Persistent and severe abdominal pain which gets worse.
  • Vomiting or unable to keep food down, particularly if this lasts for longer than 24 hours
  • Unexpected weight loss
  • Blood in your stools, or bleeding from your bottom
  • You should call 999 immediately if you display any signs of an allergic reaction, such as a skin rash, difficulty breathing, swelling of the lips, tongue, or throat (anaphylaxis)

Unlike a food allergy, which can trigger an immune response which can be serious and life threatening, a food intolerance doesn’t involve the immune system and will typically cause symptoms that cause discomfort, they are generally not considered to be life-threatening.

If you experience any of the above symptoms you should speak to your doctor.

Coping with food intolerance symptoms

There are a number of things you can try to help reduce the symptoms of a food intolerance:

  • Elimination diet: The most effective way to stop symptoms of a food intolerance is to remove your problem foods from your diet. An elimination diet is designed to eliminate those problem foods from your diet and replace them with similar foods that you can tolerate.
  • Portion control: Eating smaller, more frequent meals to prevent those signs of overeating such as bloating and a feeling of fullness
  • Eat slower: Eating quickly can lead to bloating, gas and stomachache as excessive amounts of air can be swallowed when eating quickly. Ensure you chew your food properly and slow the rate at which you eat down a little
  • Reduce stress and anxiety: Stress and anxiety have been shown to slow down the digestion process. Practicing mindful techniques such as meditation or even light exercise has been shown to reduce stress and anxiety
  • Speak to a qualified nutritionist or doctor: A qualified nutritionist should be able to help you remove your problem foods and produce a meal plan to assist with your symptoms. Depending on severity, a doctor may choose to prescribe you with some treatments to help ease your symptoms ranging from indigestion, to sickness

Testing for a food intolerance

There are a number of tests that can help you identify a food intolerance which range from a blood test to a hair test and even more conventional methods such as keeping a food diary to help you identify which foods trigger your symptoms.

A food intolerance blood test will specifically measure all 4 food specific IgG subtypes (Immunoglobulins G) to identify an intolerance to a food or its components. The Feel Gut food intolerance blood test can find intolerances to over 200 types of foods.

Other types of food intolerance tests can include a hair strand test and a breath test, typically used to identify a lactose intolerance.

Can you suddenly become intolerant to foods?

It is possible and highly likely that you will develop a food intolerance later in life, this can be due to several reasons, most commonly genetics, hormone imbalances and shifts in digestive enzymes, lifestyle factors (stress) and even underlying health conditions.

Can a food intolerance cause headaches or migraines?

Yes, although not a common symptom, headaches and migraines can be caused by an intolerance to certain foods. Keeping a food diary is effective at trying to identify which foods trigger your headaches or migraines.

Can a food intolerance affect mood or mental health? 

Yes, some foods can affect metal health more than others, for example, consuming caffeine on an empty stomach can trigger symptoms of anxiety. Certain foods can cause a spike in blood sugar and glucose levels followed by a dip which can also present symptoms of anxiety after eating.

Do food intolerances cause fatigue or low energy levels?

A food coma is commonly used to describe the feeling of fatigue or low energy levels after eating, but did you know that in the medical world this is called Postprandial Somnolence. Feeling tired or lethargic after eating is very common, it can be caused by simply overeating, energy being diverted to the body’s natural digestion process, or eating foods high in refined carbs. In some cases, it can be a sign of food intolerance, particularly if you find that a specific food seems to kick start your symptoms when consumed on multiple occasions.

Can food intolerance symptoms be delayed?

Yes, in fact most symptoms that you will experience from a food intolerance will be delayed, it is unlikely that any symptom will appear immediately after eating a food you are intolerant to. Some symptoms may appear quicker than others for example, diarrhoea symptoms can appear in just 30 minutes after eating.

Can food intolerances worsen over time?

Natural changes to our body as we age can result in a shift/imbalance of digestive enzymes which may cause new intolerances or worsen existing ones. Other factors that can influence the worsening of intolerances are lifestyle factors such as stress, exercise, and overall diet.

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