Interesting question, but I the answer isn't found in the food we eat.
1. Bullying is increasing because, in my opinion, kids aren't being taught to respect other people. It doesn't stop because those kids aren't being forced to face the consequences of their actions. Unless the bullying becomes physical, kids get a lecture they can ignore. Unfortunately, those bullies then graduate and take that behavior into the workplace and the bullying continues.
2. Young people don't want to hear this, but the school work seems to be getting harder because, for the past decade or so, schools weren't requiring the harder work most of older adults had while in school. "No child left behind" was a joke and meant "make it easier so we can get them out of here".
3. Increased rumors are a part of bullying so refer back to #1.
4. Dating is something the parents of those kids need to address.