Fewer than 1 in 10 children and 2 in 50 adults have proven food allergies. But many people think they have food allergies.

Food intolerance means you have digestive tract symptoms after eating a certain type of food. For example, lactose intolerance can cause gas, bloating, and belly pain after drinking milk. A food allergy (hypersensitivity) causes your immune system to react strongly to a food. For example, a peanut allergy can cause life-threatening symptoms. Food intolerances can be very uncomfortable. But they are not life threatening.

Also, someone with two allergic parents is more likely to have food allergies than someone with one allergic parent.

Food allergens are parts of the food that cause an allergic reaction. They are proteins within the food. These proteins aren't usually broken down by the heat of cooking . In some cases, a person with a food allergy may be able to eat cooked foods but not the raw foods.. Talk with an allergist before eating any food that you have been allergic to in the past.

An allergic reaction usually starts within a few minutes. But symptoms can begin up to 2 hours after eating the food. You may first have itching in the mouth as you start to eat the food. If you have severe food allergy symptoms, the mouth itching can quickly lead to more serious symptoms. These include hives, coughing, shortness of breath, swelling, vomiting, diarrhea, and drop in blood pressure. In some people this happens within minutes of eating a food. For other people, the symptoms take longer to develop. The amount of food eaten can affect how fast symptoms appear and get worse. Exercise, , illness,or asthma also can affect this.

Children are more likely to outgrow allergies to milk, eggs, or soy than allergies to peanuts, fish, or shrimp.

This is called cross-reactivity. Proteins in melons are similar to proteins in ragweed. People with ragweed allergies might find that eating cantaloupe will cause itching in the mouth. An itchy mouth is not often a symptom of a severe allergy. But if a food causes your mouth to itch, don't eat it again until you talk with your allergist.

Meat contaminated with bacteria can cause what seems to be an allergic reaction. But it's really a form of food poisoning. Some fish that are spoiled or kept at too warm a temperature have high levels of a chemical called histamine. This may cause what appears to be an allergic reaction in some people. This reaction is called scromboid (histamine) toxicity.

Once you and your healthcare provider have identified the food that you are sensitive to, you'll need to remove the food from your diet. Do this even though other types of treatments are available or being developed. To remove the food, read the ingredient list for each food before you eat it. Many allergy-causing foods such as peanuts, eggs, and milk appear in foods that you may not think they would be in. For example, peanuts are often used as a protein source. Eggs are used in some salad dressings. Talk with your healthcare provider about treatments available for food allergies.