Ok well this has probably been said but hey i'll make sure.
A dream is a way for your Sub-conscious to work through problems, emotions ect. If you obtain lucidity too often and change the way the dream would naturally shape itself then you can (im not saying you always will) you can pull away from what your mind is working on, this would cause emotions to run alot higher, quite often the more negative emotions - anger, depression. Also in this you can lose sense of reason and then you become a danger to yourself and others around you.

Its just a warning and im not saying stop doing it, im just saying make sure that if a dream feels like it needs to play out then let it and just follow what the dream wants.

Happy dreaming