What are the symptoms of a food intolerance?

When you have a food intolerance it can lead to the below symptoms which can affect your performance and enjoyment of life and make you feel miserable, especially if you have tried everything.

  • bloating
  • constipation
  • diarrhoea
  • fatigue
  • flatulence
  • headaches
  • inability to lose weight
  • long-term joint pains can persist for years
  • skin problems

As an experienced nutritional therapist working with people with food intolerances and other digestive symptoms, I have found that it is possible to find out what is going on. If you have been blaming the food or foods for causing your symptoms, it could be caused by a number of different digestive factors that I can help you work out and fix.  

With that in mind, I would start differently by looking at the underlying cause of your symptoms before cutting out loads of foods that may actually be beneficial, even though they may be making your symptoms worse at the moment. The biggest difference I often see is by first working on your diet and considering undertaking some digestive and microbiome function tests. 

Understanding food intolerance 

Before explaining how I can help you, it is important to explain what a food intolerance is.  

An intolerance to food, strictly speaking, is when we lose production of an enzyme so that we lose the ability to digest certain foods, such as individuals with a lactose intolerance, which makes it harder to digest milk and dairy. You may also have a problem with histamine-containing foods.

A food sensitivity, on the other hand, arises when food particles enter the bloodstream, prompting the body to react as if they are foreign substances. This reaction involves the production of specific IgG antibodies and elevated levels of an immune complex, called complement. Symptoms can occur as soon as 30 minutes, three hours or even longer in some cases. 

A true food allergy is a lifelong condition triggered by IgE antibodies. Allergic reactions develop rapidly, within two hours of consuming the allergen, and can be life-threatening in severe cases.

Identifying food intolerance symptoms

If you suspect you have a food intolerance, there are several steps you can take:

Maintain a food diary

Keeping a detailed record of all foods and drinks consumed daily, along with any associated symptoms, can help identify specific triggers.

Consider a food intolerance test

A food intolerance test analyses IgG antibody reactions to various food and drink ingredients. The presence of food-specific antibodies may indicate a potential sensitivity. This is something I can arrange for you. There may also be other causes of your digestive discomfort, such as a small intestinal bacterial overgrowth or low digestive enzyme production. I can also arrange testing for these as well.

Identifying the trigger food

Once the trigger food has been identified, I will be able to guide you on how to replace the trigger food while ensuring a balanced diet that provides all necessary nutrients. The support of a nutritional therapist like me is invaluable during the challenging process of following an elimination diet and re-introduction of foods.

A note from Nutritionist Resource:

There are a number of ways food allergies can be tested and diagnosed. The Association of UK Dietitians lists tests that can be helpful and those with little supporting evidence to help you decide which route may be best for you.

Supplements and lifestyle factors 

In addition to dietary changes, certain supplements and lifestyle factors can further support managing food intolerance symptoms, including the following.

Digestive enzymes

Supplementing with digestive enzymes can aid in the breakdown of food components, improving digestion and reducing symptoms.


Adding probiotics to your daily routine can help restore a healthy balance of gut bacteria, promoting optimal digestion and gut health.

Stress management

Mindful eating is a practice that can significantly reduce symptoms of food intolerance by bringing full awareness to the present moment while eating. Mindful eating allows you to observe any adverse reactions or discomfort that may arise after consuming trigger foods, helping you to identify specific intolerances more accurately. Mindful eating also promotes a relaxed and calm state, reducing stress-related symptoms often associated with food intolerance. 

Adequate hydration

Proper hydration is essential for maintaining healthy digestion. Aim to drink enough water throughout the day.

It is often tricky to work out what you are reacting to and the reasons why, but it is possible, with my help to help you restore proper digestive function and provide you with effective solutions.  

If you suspect you have a food intolerance, please get in touch with me for a complimentary call. 

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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London SW15 & W1H
Written by Melody Mackeown, mBANT, CNHC, BSEM | Nutritional Therapist and Health Coach
London SW15 & W1H

Melody Mackeown, is a Nutritional Therapist who works across the UK and world-wide.

If you are looking to work with an expert who can help you figure out the best foods for you without the guesswork or faddy diets you are in the right place. Together, we can help figure out the root cause of your digestive problems and find effective solutions.

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