Trying to sort out which foods a baby is allergic to is like trying to solve a difficult jigsaw puzzle. The doctor and dietitian solve the puzzle piece by piece until they have a complete picture. These three following steps give an overview of how the pieces of the puzzle may be put together.

The first step in trying to solve the food allergy puzzle is to get the child as well as possible, that is ideally symptom free, gaining weight and growing well. At this stage, the baby may be receiving all or most of their nutrition from an hypoallergenic infant formula, prescribed by the doctor or dietitian.

Depending on the age of the child and the allergic symptoms, few foods or perhaps no food may be permitted at this stage.

The few foods permitted are usually foods known to be the least likely to cause an allergic reaction (link to the proper content) in the majority of babies and children with symptoms similar to those in your child. It is important to only give those foods recommended by the doctor and/or dietitian to give your baby the best chance of becoming well as quickly as possible. Do not add flavourings, seasonings or any products without checking every ingredient is permitted.

Second step - Introducing new foods

Once a baby is doing well on hypoallergenic infant formula and permitted solid foods, the doctor and dietitian will allow new foods to be tried. This is often referred to as the food “challenge” phase. The aim in doing this is to sort out which food/s the baby is allergic to and to broaden the child's diet as much as possible.

In this step, it is important to continue taking the prescribed amount of hypoallergenic infant formula, as it continues to be the major source of nutrition for the baby. Some of the formula can be mixed with the foods offered. Follow the doctor and dietitians instructions exactly.

Here is some basic roles to properly introduce new foods in a baby's diet:

• Foods should be introduced one at a time. This way, if a baby has an allergic reaction to a food it can be traced quickly
• Only introduce new foods when the baby is well
• Small amounts should be given at first. A “pea size” amount (1/4 – 1/2 teaspoon) is given the first time. The amount can be gradually increased over several days if there are no symptoms. If symptoms occur to the new food, it is important to stop the food being tested, record the symptoms and discuss them with the doctor or dietitian. Wait approximately one to three days after symptoms have ceased, before giving another new food
• Try to give a new food every one to two weeks, continuing on a regular basis those foods that have already been introduced and tolerated
  Recommendations may vary from clinic to clinic. Always follow the advice of your doctor and/or dietitian
• Discuss with your doctor or dietitian when it is safe to re-test foods that initially caused a reaction

Third step - Introducing more foods

As new foods are introduced and tolerated, the baby's diet can become more varied. Different food combinations and recipes using the permitted ingredients can be introduced.

At this stage, the amount of required hypoallergenic infant formula may be decreased or ceased altogether, being replaced with another formula or soy formula or cow's milk if tolerated. This needs to be discussed with the doctor and/or dietitian. They will assess the nutritional adequacy of your baby's diet and adjust the amount of formula accordingly. The doctor and/or dietitian will also offer advice on alternative sources of calcium and other nutrients if milk still isn't tolerated.

This process can take some time to complete. It can be a difficult time for both parents and the child. Young children can outgrow food allergies.

It is important to consider “re-challenging” the baby at a later date to those particular foods to which he initially reacted. This must be discussed with your doctor.