Food Allergy and Intolerance in Sport


Food and drinks are important parts of an active person’s preparation, competition and recovery strategies. Importantly, people with food intolerances must be aware that exercise can exacerbate reactions in some situations and therefore need to ensure they adhere to their requirements to help manage symptoms. It’s important to establish a nutrition strategy that meets an individual’s dietary requirements, while still maximising performance.

What is a food allergy?

Food allergies are an immune response from the body to an otherwise harmless food item. The reaction usually leads to symptoms, such as hives, eczema, facial swelling, vomiting and breathing difficulties within 30 minutes after allergen ingestion. They are most common in children up to the age of four, but some allergies continue into adulthood. Common foods that cause allergic reactions include: cow’s milk, egg, peanuts/tree nuts, sesame, soy, wheat, and shellfish. Diagnosis occurs by a skin prick test or blood test by a GP or immunologist.

What is food intolerance?

Food intolerances are more prevalent in adults than in children and unlike an allergen, cause a non-immune response. It is normally dose related, meaning the more you eat the worse the reaction. There may also be a threshold amount required to be consumed before experiencing any symptoms which can makes it difficult to determine the specific cause. The symptoms of food intolerance include: hives, stomach/bowel irritation (e.g. cramps, gas, pain, bloating, and loose stools), headaches, fatigue, mouth ulcers, aches and pains and / or sinus congestion. Depending on the type of symptom there is a number of ways to approach the dietary treatment of food intolerances.

Treatment of food intolerances & allergies

For some food intolerances with gastrointestinal symptoms it may be beneficial to consider a low-FODMAP diet approach. For more information see the FODMAP factsheet. Treatment of food allergies requires that all allergens must be removed completely from the diet. In either case, an athlete should consult their GP and Accredited Sports Dietitian for advice on the best course of action when treating food allergy or intolerance. For considerations relating specifically to Coeliac Disease, please refer to our factsheet for more information.

Avoiding food allergies during exercise

The best way to avoid a reaction and complications while training and competing is to avoid the allergen. This means being aware of what foods contain the allergen, what foods probably contain the allergen and being aware of foods that the allergen may be contained in (usually in a lesser amount and possibly hidden in the food). If there is any doubt about whether a food is safe to consume it is better to err on the side of caution, not eat the food and find something safe to consume.

Assisting an athlete with a food allergy

Anaphylaxis is a potentially life threatening allergic reaction which can include tightness in the throat, swelling of the tongue and loss of consciousness. If someone is experiencing an anaphylactic reaction, and they carry medication, it needs to be administered immediately and an ambulance called. The ambulance must also be notified that the person has had an allergic reaction and medication has been administered.

Many athletes with allergies will have a plan including the administration of antihistamine at the first signs of a reaction to help to ease the likelihood of a full anaphylactic reaction. For someone with a diagnosed food allergy they would generally be advised to carry a self-injectable adrenaline dose in case of an emergency.

There is a condition called food-dependent exercise-induced anaphylaxis and this occurs when a particular food and exercise are combined together (when independent of each other, the food or the exercise doesn’t cause a reaction). With this condition, it is advisable for athletes to avoid the particular food before exercise (2-6 hours before) and to carry their self-injectable adrenaline syringe (epipen or anapen).

The athlete’s doctor must be aware of the person’s reaction and co-ordinate an allergy action plan for the athlete. The coach and team manager must also be aware of this and know how to follow this action plan ahead of time, so that if occasion arises, they are able to follow the plan quickly and easily. The self-injectable adrenaline syringe needs to be with the person at all times and even when exercising. Support team members should be familiar with how to use this if required.

Allergies, intolerances and sports foods

While everyone’s allergy or intolerance is individual, there are a number of points that are worth considering with regards to sports foods. Although this list is not exhaustive and does not replace individual advice, below are a number of sports foods and the ingredients that may cause difficulties in some athletes:

  • Sports drinks: Fructose, flavour, colour, whey protein, herbal preparations
  • Sports gels: Fructose, flavour, sodium benzoate, potassium sorbate, chamomile, cola nut, ginger
  • Sports bars: Fructose, gluten, barley, malt, flavour, cocoa powder, skim milk powder, nuts, oats

More information

For more information about allergies and intolerances, good places to start include:

For more information on this or other sports nutrition topics, subscribe to our newsletter or book to see an Accredited Sports Dietitian.