Pretty much anything can cause a chemical balance at any point. Too much of anything, food, sleep, exercise, and conversely too little of anything can do the same.
The danger comes when people try to alter the balance without knowing exactly what they are doing or what will happen when they do. Ask any doctor, they have no idea how antidepressants work, only that they seem to work, so why not try it. Why not? They deplete your production of natural chemicals in the brain, thats why not. Its the reason it is so hard to go off antidepressants.