Does smoking lead to or prevent depression?

Unclear: Research on this is still being done. At this point "the evidence is stacked against nicotine as a mood lifter, despite widely-held beliefs to the contrary, " according to a review article: http://psychcentral.Com/lib/2011/can-smoking-cause-depression/ smokers have higher rates of depression than nonsmokers. A smoker's expectations of the effects of smoking are important in the short term.