People with food allergies exhibit abnormal immune system responses certain foods. These allergic responses can be mild or severe, such as anaphylaxis, which can cause shortness of breath, nausea, swelling at the back of the throat, and a weak pulse. While some people outgrow their food allergy, others may have to contend with them their entire life.

1. Peanuts

Peanut allergies are quite common. Medical researchers aren’t entirely certain what causes this allergy, but evidence suggests it is hereditary. For now, there is not an effective treatment for this type of allergy — people allergic to peanuts must avoid them. About 20% of children with a peanut allergy outgrow it by the time they reach adolescence. However, in some cases, the allergy remains severe. In extreme cases, children may require constant supervision or even a service animal trained to sniff out the presence of peanuts.

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