Food allergies

Intolerances are adverse reactions to food or food components in which the immune system does not intervene and generally do not cause dangerous reactions -Anaphylactic Shock- as do allergies; however, when they are not discovered and treated in time, they can affect health in a chronic way.

They are between 5 and 10 times more frequent than allergies; it is estimated that 1 in 4 Spanish adults suffer from some type of food intolerance, which in many cases arise from early childhood.

The symptoms of food intolerances generally appear more slowly, so they are often not associated with the food that causes them and the individual continues to ingest them and gradually affecting their health, which can cause damage to the digestive system.

Usually, individuals who show intolerance to a food can consume small amounts of these without any noticeable symptoms; in addition, most of the disorders - colic, headache, stomach aches, urticaria, itching, headache, hyperactivity, anxiety, etc. - caused by intolerances, occur very similar to those caused by allergies, but with less intensity.

Origin of food intolerances

Enzymatic: These occur when the body is deficient in certain digestive enzymes. Examples of these are lactose and fructose intolerance.

Pharmacological: They occur when substances present in the food or released by it, have a known pharmacological effect. Example: patients who react pathologically to amines (which widen or narrow blood vessels) present in some foods, such as those containing caffeine.

Metabolic: The reaction depends on the action of the food on the host's metabolism. The reactions do not produce the same symptoms.

Indeterminate: The abnormal response to a food not associated with immune system responses of unknown cause.

Most common food intolerances

Among the most common food intolerances are lactose intolerance, gluten intolerance and fructose intolerance.

Lactose intolerance

This is one of the main food intolerances described. Lactose is present in the milk of all mammals in proportions between four and five percent, it is known as the milk sugar.

Lactose intolerance occurs in some individuals who present a more or less important deficiency of a digestive enzyme called lactase; this is found in the small intestine and is responsible for fractioning lactose into smaller units -glucose and galactose- to be digested.

When lactase deficiency causes lactose to pass into the large intestine intact and is fermented by the bacteria of the intestinal flora, hydrogen and other gases are generated, which cause the symptoms of lactose intolerance.

Symptoms usually include abdominal cramping and bloating, flatulence, diarrhea and vomiting.

Characteristics of lactose intolerance:

• Symptoms appear between thirty minutes and two hours after ingesting lactose-containing foods and disappear between 3 and 6 hours later.

• The inability to digest lactose may increase with age.

• Symptoms of intolerance in individuals with low lactase levels develop in most cases when large doses of lactose are consumed.

• A high proportion of lactose-intolerant individuals can consume moderate amounts of milk without intestinal discomfort.

Treatment of lactose intolerance: It is the pediatrician who is in charge of suggesting the most appropriate treatment taking into account the symptomatology of each child. Most children are able to tolerate a certain amount of lactose in food without problems and in case of accidental events due to exaggerated ingestion, it is enough with the partial or total withdrawal of the food to achieve the disappearance of the symptoms.

If the child must follow a diet that cannot include milk or any of its derivatives, it is important to supplement it with foods rich in calcium, vitamin D, riboflavin (vitamin B2), etc.; or with nutritional supplements appropriate to the child's age, oriented by the pediatrician.

Fructose intolerance

Fructose is found naturally in fruits, vegetables, beets, sugar cane, honey and in some industrial products where it appears as an artificial sweetener. In individuals intolerant to fructose, there are failures in the absorption of fructose in the small intestine, and when it passes to the large intestine and is fermented by bacteria, abdominal pain, bloating, and diarrhea occur.

To prevent the symptoms of fructose intolerance, children should follow a diet restricted in fruits and vegetables, which represents a high nutritional risk since these foods provide significant amounts of vitamins, minerals and bioactive substances that are essential for the proper growth and development of children.

Non-celiac gluten intolerance or sensitivity

Gluten is a protein found in cereals -mainly in wheat, but also in oats, barley and rye or any of their