Food intolerance is often confused with food allergy; however the symptoms and reactions are very different.  Allergy is an immediate adverse reaction by the immune system to a specific food, which in some cases can be very severe and can lead to death.  On the contrary, food intolerance is usually less serious, sometimes appearing hours or days later.  With an allergy even ingesting the tiniest amount of the offending food will cause a severe reaction, however with food intolerance you may be able to eat small amounts of it without having any symptoms.

Signs of food allergies can range from rashes, swelling, diarrhea, vomiting, stomach ache and asthma among others.  Most severe cases can include swelling of the lips and tongue, difficulty breathing, and loss of consciousness, which can lead to an anaphylaxis shock and death.

Symptoms for food intolerance are much more varied and can include migraine, bloating, diarrhea, and a general feeling of unwellness.  Common food intolerances include lactose, gluten and additives among others.