Though it is often difficult to determine if an individual is sensitive to some kind of additive, it is often even more difficult to determine which additive is responsible and what level of sensitivity is involved. The first step often involves an individual creating a complete food diary with the help of a physician. While keeping this diary, patients will be asked to record all the foods they consume, the time food is eaten and the time reactions occur. By closely observing which foods trigger a response, a physician can often pinpoint additives that are more likely to blame.

After determining which additives may be responsible for causing symptoms, some physicians recommend an elimination diet, which involves avoiding any foods that may contain the problem additives. By observing the patient’s reactions or lack of reactions through this stage, the physician can further determine the individual’s susceptibility.

Because some reported symptoms may be similar to food allergies, a physician may recommend one or more allergy tests to rule out an allergic cause.