Can you lend me a jar of love?

http://en.wikipedia.org/wiki/Tobacco_smoking

Data from multiple studies suggest that depression plays a role in cigarette smoking.[23] A history of regular smoking was observed more frequently among individuals who had experienced a major depressive disorder at some time in their lives than among individuals who had never experienced major depression or among individuals with no psychiatric diagnosis.[24] Another study found that the average lifetime daily cigarette consumption was strongly related to lifetime prevalence, and to prospectively assessed one year prevalence of major depression.[25] People with major depression are also much less likely to quit due to the increased risk of experiencing mild to severe states of depression, including a major depressive episode.[26] Depressed smokers appear to experience more withdrawal symptoms on quitting, are less likely to be successful at quitting, and are more likely to relapse.[27] The neurotransmitter systems affected by cigarette smoke mirror the neurotransmitter pathways that are thought to be involved in the biological mechanisms of depression, and the use of antidepressants as adjuvants to smoking-cessation treatment can enhance cessation success rates.[28]