No food actually causes eczema. Instead, there are some foods which for some people can trigger the flare up of eczema. It’s an important difference to recognize since you can remove the offending foods from your diet, but the eczema may persist.
Children are born with eczema
Children are born with a genetic predisposition toward eczema. Some things, including some foods, can make it worse. They aren’t the cause of the eczema, but they are responsible for making it worse. Eczema results from an imbalance in the immune system. As a result, children may become sensitized to common substances in the environment (like food or pollen). A food allergy or a food sensitivity can make eczema worse as a result. Removal of the food can improve, but not cure, the eczema.
How to find out if food is making your eczema worse
There are two primary ways. First, there will be an immediate reaction including redness and itching of the skin usually within an hour of eating the food trigger. These reactions are associated with allergy and are due to the food reacting with the IgE antibody in most cases. Second, the delayed reaction can occur over 24-48 hours after ingesting the food. These reactions are thought to be related to the food proteins aggravating immune cells or T cells. A skin prick test will confirm the first, immediate reaction, but not the delayed reaction. The only way to know if a specific food causes a delayed reaction is by experience. Remove the food and see what happens. Reintroduce the food and watch the skin. If there is a reaction, keep the food out of the diet.
The most common food triggers
The most common triggers are cow’s milk, chicken eggs (both white and yolk), wheat and peanuts. If you try an elimination diet to test for skin reaction, start with these foods. A commonly experienced eczematous rash found around the mouth is caused by eating highly acidic trigger foods like orange, tomato and strawberry.
Source: Sydney Children’s Hospital