How to identify allergic reaction

Dear Ellen,
A food allergy results from an adverse reaction to food that involves an antigen-antibody or antigen-cell interaction. This is in contrast to a food intolerance, which does not involve the immune system. A food allergy is only one of many causes of adverse reactions to food. Other reasons include such things as the absence of digestive enzymes — for example a lack of lactase will cause an inability to digest the sugar in milk — and toxins or harmful bacteria in food.

A true food allergy can really only be diagnosed by a medical professional. You should keep an eye out for any adverse reaction to a food. Symptoms that may indicate an allergy or other food sensitivity include excessive wind and bloating, diarrhoea, vomiting, skin rash, sneezing, runny nose, wheezing and unusual crying (perhaps caused by cramps). If you notice these signs, you may want to keep a food intake/symptom diary for a few days. Take this to the doctor in order to help her make a diagnosis.

A nappy rash can be caused by any number of things and so would be a little hard to use as an indicator of a food sensitivity. However, it certainly can be caused by it. Any food intolerance symptoms can be subtle or severe and their seriousness depend on many factors such as the amount of food the baby ate, how sensitive he is to the food and how tolerant he is of discomfort.