My son has been on the diet for several months now, with positive results. He recently ate a hamburger bun, and there has been no regression. What does this mean?

1. Sometimes there is no reaction. There can be several reasons for this. Two of the most obvious are:
a) The gut may have healed to some extent
b) The patient's enzyme system may have started to function again.
2. Sometimes, there is a reaction, but it gets overlooked. There are at least two reasons for this:
a) People don't know what signs to look for, and tend to overlook the subtler symptoms that something is wrong.
b) Time delays: Infringement reactions follow different patterns, and some of the more obvious signs can be delayed by anything up to 3 days. When they eventually appear, they are not overlooked, but the connection with the infringement is.
Warning: Even if the first diet infringement appears to have had no effect, you should be very careful. There are several stories about families who have reintroduced "normal" intake of gluten and milk, and who have managed to overlook the subsequent severe regression for up to six weeks because it was so gradual.
In older kids who have dramatically improved or recovered on the diet, the reintroduction of gluten doesn't necessarily make them autistic. We have received reports that after a few weeks some may become delusional or even schizophrenic.
There are several reasons why this can happen:
1. Gut damage can re-occur after repeated exposure to gluten or milk in allergic individuals
2. Yeast / fungus / anaerobic bacteriae may re-colonize the gut if the patient goes off the diet, and can damage the lining of the gut wall
3. Habituation or bell-shaped dose response curve
(do keyword search for more information)