The main allergenic foods listed in order from highest to lowest frequency are: peaches, milk, eggs, melon, prawns, fish, kiwis, bananas, walnuts, watermelon, peanuts, apple, tomato, and hazelnuts. In children younger than four the highest number of reactions is to cow’s milk, eggs and fish. Prevention consists not only in excluding foods that contain the allergen but also in reading the labels of manufactured foods prior to consumption and warning cooks about people with allergies.
It’s caused by metabolic alterations that impede the digestion, assimilation and exploitation of certain substances that foods contain. The symptoms it provokes are varied: they include gastric discomfort (flatulence, diarrhoea and intestinal colic), migraine and a sensation of heat. One of the best known is lactose intolerance, lactose being a sugar present in dairy products. It results in chronic diarrhoea and causes nutritional deficiencies. Such an intolerance can be temporary in children under two. The recommended diet involves the elimination or reduction of foods containing lactose, according to the degree of intolerance. Lactose-free cow’s milk can now be found on the market as well as substitutes such as products made from soya, oats, almonds, hulled wheat, etc.
They occur when the immune system reacts to a specific substance (allergen) that the majority of people tolerate. The allergy is typically a food protein that enters the sufferer’s organism by ingestion, contact or inhalation. The most common reaction is the creation of IgE antibodies (immunoglobulin E), something that does not occur with intolerance. One of the most common food allergies is coeliac disease in which the gluten present in cereals such as wheat, barley, rye, oats, hulled wheat and khorasan wheat causes a toxic reaction in sufferers. By eating gluten they damage the mucous membrane of the small intestine which triggers fatty diarrhoea and a swollen abdomen.
A lifelong exclusion of foods containing gluten from the sufferer’s diet is required. Nowadays there are many products suitable for coeliac sufferers, many of them made from rice and maize. Another allergy that is typical of childhood is allergy to the proteins contained in cow’s milk and the symptoms can be cutaneous, respiratory – such as coughing, rhinitis and so on – or digestive. The dietary remedy consists of entirely eliminating proteins from cow’s milk. It is possible to find foods that are free of cow’s milk proteins in pharmacies and specialist dietary product shops. It is advisable to pay special attention to foods associated with high allergenic risks (fish, eggs and cereals containing gluten) and introduce them gradually into the diet.