The symptoms of food intolerance are incredibly varied and can affect almost every body system. In some people the symptoms are persistent while in others they come and go. As with the definition of the condition, the symptoms attributed to it are often disputed.

The list below summarises the symptoms most commonly  agreed upon.

• Headache

• Migraine

• Anxiety/Depression and changes in mood

• Fatigue

• Hyperactivity (most commonly seen in children)

• Recurrent mouth ulcers

• Recurrent throat infections

• Aching muscles

• Vomiting

• Nausea (from mild to severe)

• Stomach and Duodenal ulcers

• Diarrhoea

• Irritable Bowel Syndrome (IBS)

• Constipation

• Rapid weight loss (in some cases weight gain)

• Wind/trapped wind and bloating

• Crohn’s Disease

• Joint pain

• Water retention
  
  
• In up to 50% of cases, patients may crave the food(s) to which they are intolerant. 

The above symptoms are indicative of many illnesses and anyone who believes they may have a food intolerance should seek advice from a qualified medical practitioner to rule out any other possible causes first. If after this no satisfactory conclusions can be made the possibility of food intolerance should be seriously considered.