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Food sensitivity basically means that the body responds in some adverse way to the consumption of a food or the consumption of a component, like a protein or chemical, that is in the food. Scientists identify two sensitivities that may occur. Sometimes the body responds to food with an immune system reaction and this is called food allergy. At other times, other body system, and not the immune system, will cause a variety of symptoms, and such a response suggests a person is intolerant to a certain food or part of it.
By part of food, it should be meant that a single food is being discussed. Its elements, such as sugars, proteins, and fats may be the culprit in a food sensitivity. When it is possible to eliminate the likely offender and consume the food without the element, people could possibly tolerate the whole food. Since many foods consumed are made up of a number of ingredients, this work gets harder. Each ingredient would have to be broken down to smaller levels to find out what component is creating the issue, and this is further complicated by the fact that people can eat many different multi-ingredient foods in a single day.
In food sensitivity, food allergy is likely to have a more immediate reaction than food intolerance. This reaction could be very serious, and some people with severe allergies will experience anaphylactic shock if they have even the tiniest exposure to an allergy causing food. Allergic reactions may also worsen with each subsequent exposure, making it extremely important for those with common food allergies, such as to peanuts or shellfish, to observe careful food handling and preparation.
In contrast, food sensitivity that is intolerance doesn’t always express itself right away. People might not notice symptoms of a problem until a few days after a food is consumed. These symptoms are greatly varied. Yet, commonly diarrhea, nausea, vomiting, or gas production suggest food intolerance. If more hayfever like symptoms develop, or if asthma or hives are present this could be a food allergy instead.
People with gastrointestinal problems that have not been successfully diagnosed may have food testing, often by eliminating certain foods and seeing if symptoms improve. Those with allergies could also have testing to determine which foods are problem foods. When food sensitivity, like lactose intolerance, is diagnosed, people are usually told to avoid that food in the future. With things like lactose intolerance, there may be other measures of control like taking lactase, and eating dairy with natural cultures in it.
These measures usually aren’t open to those with true food allergy. With food intolerance people may weigh whether they want to pay for consuming something they enjoy with a stomachache or worse. When allergy is present, serious risk to life may occur with each consumption, and eating foods to which a person is truly allergic is unwise and unsafe. In some instances very strong reactions to an intolerant food suggest simply eliminating that food from the diet too.