When a person has a food allergy they have symptoms closely related to eating the food, maybe within a few seconds or minutes. The immune response of a food allergy described is a clear reaction happening after eating the food in question.
A true allergy will have an immune response, which means, that when your body is exposed to a food that you are allergic to, you will have specific symptoms that occur every time you eat that food and it may be detectable through a blood test.
Symptoms to look out for are:
- Itching of the mouth can be an immediate symptom with onset within seconds of the food being placed in the mouth.
- Swelling of the face may happen on eating the food to which the allergy sufferer is sensitive The swelling of the face can occur soon after. The swelling can affect the lips, cheeks and commonly the eyelids. This is known as angioedema and can last for a few hours until it resolves. Facial swelling would happen EVERY time the food is eaten if a food is causing the swelling. However it is rare that this type of swelling of the face is caused by food and it is most commonly “idiopathic” in other words without a known cause.
- Swelling of the tongue, lips and throat can come on after a few minutes and can be quite dramatic. This can have a rapid onset within minutes.
- The symptom of tongue and lip swelling can be very extensive and can last for a few hours or longer until it resolves.
- Swelling of the tongue and lips would happen EVERY time the food is eaten.
- Abdominal pain (stomach cramps) and vomiting may also occur if the food to which there is an allergy is swallowed. This is because of the reaction to the food happening in the bowel wall.
- The swelling of the bowel wall can cause the symptoms of pain soon after ingestion of the food and the symptoms should resolve within a few hours. Abdominal pain or vomiting would happen EVERY time the food is eaten.
- Diarrhea is a symptom that would happen each time after eating an allergy food.
- A widespread rash would occur with a food allergy within half an hour of eating the food.
The food is absorbed throughout the whole body and therefore the rash would be over a larger area of the skin. The rash is itchy with weals that can look like nettle stings. These are called urticarial plaques and are not eczema.
They are smooth, raised and red. They resolve within a few hours but would return EVERY time the food is eaten. The immune response of a food allergy described above is a clear reaction happening EACH TIME the food in question is eaten.
Anaphylactic shock
The most severe and dangerous food allergy is anaphylactic reaction so severe that it causes shock. This can be to nuts and other foods. The next article explains what to look for to diagnose anaphylactic shock.
Identifying culprit foods
Many people may feel that when they eat certain foods that their skin problem gets worse.
If this is the case, then try keeping a food and symptom diary. Write down everything that you eat and drink and how good or bad your skin problem is.
You may find it helpful to devise your own grading scheme for your skin problem;
- 1 – the best
- 10 – the worst it can get
You may need to keep this dairy for a few months, as it often takes some time for your skin problem to change. Remember to make a note of anything else that may effect your skin problem such as stress, menstrual cycle, low mood, alcohol, medication etc.
Then, have a think about the connection between all these things. For instance, you may find that when you are stressed your diet is poor and you tend to eat more of the things that you feel make your skin problem worse. So, your skin problem may be worse because of stress rather than being related to your diet.
It can be difficult to figure all this out. You may need help in keeping and understanding your dairy. If you still feel that certain foods have a direct effect on your skin problem then you may want to try an elimination diet.
When to use an elimination diet?
People can suffer with sensitivity to foods. The most common suspects are:
- Dairy
- Wheat
- Nuts
- Eggs
If you wanted to test one food to assess if you had an allergy/intolerance to it, you have to find a marker to measure the effect of removing that food. Generally you would use the symptom that you are suffering with as your measure, in other words your rash/eczema/psoriasis/itch. For example: if you have eggs for breakfast and five minutes later your big toe on your left foot goes purple, you could use this as a marker!
In the same way, you should look for a clear link between your diet and your eczema/psoriasis/rash/itch. The foods that are eaten prior to a flare up should be written down.
It can be difficult to do this on your own, having someone to give you guidance and support can aid in diagnosis
REMEMBER
Most patients blame foods on flimsy grounds. Proper followup and study is needed to identify that patient has food allergy.
