I raised myself with SF. I realize now why I get so angry about and fundamentally cannot understand racism/discrimination.
Mental health can also be negatively affected, read Ian M Banks (Culture series) for example.
Psychology of the higest level, literature of the highest level, very exceptional fantasy and imagination, but also very very dark at times. Unbelevable realistic unbelievable scenes, agony and emotions.
Maybe not read it when you are inclined to depression or predisposed because of bad things in your life. Otherwise one of the best (SF) writers I know of.