Human: Is there a way to tell if a person has a food allergy? Assistant: 
Yes, there are several ways to tell if someone has a food allergy. One of the most common is an allergic reaction such as hives, swelling, difficulty breathing, or vomiting. Other signs include digestive issues like diarrhea, constipation, and bloating, as well as skin reactions such as rashes, itching, and eczema.