You’ve probably been there before: you eat something and you immediately feel a reaction in your body. Even worse, you may be itchy, your stomach is bloated, or you feel sick. You then wonder if you have developed an allergy to the food you just ate or if you are simply sensitive to it.

Food intolerance and allergies are easily and frequently confused. Although the symptoms of food allergies and intolerances can overlap, it is very important to know the difference between the two.

For example, a food intolerance can cause you to feel embarrassed or unwell after eating a food to which you are sensitive. While the symptoms you experience after consuming a food you are allergic to can be much more severe.


Food intolerance or sensitivity occurs when your digestive tract is unable to break down and process food properly. Unlike food allergy, food intolerance only affects the digestive system, so the symptoms are less severe than those of an allergic reaction. Your body may be unable to properly process certain foods, and therefore have a food intolerance, for several reasons, including the following:

An enzyme deficiency:

Digestive enzymes speed up chemical reactions in our bodies that allow nutrients in food to be broken down and transformed into substances that the digestive tract can then absorb. Therefore, when we lack enzymes, food cannot be properly broken down and absorbed through digestion. Lactose intolerance is a common example of food intolerance due to enzyme deficiency.

Sensitivity to food additives:

Additives are usually added to foods to preserve them or change their taste or color. Food additive sensitivity is when a person has an adverse reaction to certain additives in food. A common example is a sensitivity to sulfites in canned fruit or wine.

Irritable Bowel Syndrome:

Irritable bowel syndrome (IBS) is a chronic digestive disorder affecting the large intestine and causing a range of symptoms including cramping, gas, abdominal pain, bloating, constipation and/or diarrhea. Consuming certain foods and beverages can trigger IBS symptoms, including milk, wheat, citrus fruits, cabbage, and carbonated drinks.

Celiac disease:

Celiac disease is an autoimmune disease of the intestine in response to the consumption of gluten, a protein found in wheat, barley and rye. It’s not a food allergy or intolerance, and eating foods with even small amounts of gluten can trigger an immune response that damages the small intestine.


Symptoms of food sensitivity are milder than those of food allergies. They often manifest as an upset stomach and can occur a few hours after consuming the food, with the reactions occurring as the food moves through your digestive tract. Common symptoms of food intolerance are:

  • Stomach ache.
  • Abdominal pain.
  • Nausea.
  • Diarrhea.
  • Gas and bloating.
  • Headache.
  • Stomach pains.


Unlike a food allergy, food sensitivities do not require immediate treatment. However, avoiding or reducing the consumption of foods to which you are sensitive may help reduce symptoms.

An elimination diet can help you feel more comfortable and identify the foods that are giving you trouble. This involves eliminating certain foods that you think are causing the problem for two or three weeks. You can keep a food diary to record everything you eat and how you feel. Then, once this period has passed, you can reintroduce the foods and note any changes.

In addition, other medical problems can be the cause of your food intolerance, such as celiac disease or irritable bowel syndrome. If so, these conditions need to be treated and may ease your food intolerance symptoms.

* criptom strives to transmit health knowledge in a language accessible to all. In NO CASE, the information given can not replace the opinion of a health professional.