To the best of my knowledge, no one really knows. In fact, no one is really even positive that imbalances cause such disorders.

However, some imbalances make sense. Hormonal imbalances can be traced to diseases, weight, and monthly cycles in some cases. Also, drug intake, certain foods, and lack of sleep can alter your body chemistry.

I have a mild bi polar disorder. No med ever corrected my balance, so I choose to manage my illness with good sleep, not drinking too much, eating well, and learning more about my illness so that I can identify behaviors that can be affecting my mood and ability to function. For example, I try to identify black and white thinking so that I can be open to see things in a more proactive way and I try to identify behaviors such as grandiosity so that I can identify if I am in an up and then be careful.

Hope this helps.