also, is that when there are many food allergies at play, your Dr. should be carefully charting weight
percentiles, to be certain he is on track and getting the proper mix of nutrients on a daily basis from other foods, etc., which he isn't allergic to.
Sometimes a nutritionist is able to help if this occurs ....
My daughter was below the charts for 2 years ..... back then, nobody realized or took food allergies seriously. Today, it is so much different.