" Addiction to softer drugs like alcohol or pot can be just as damaging but more insidious. The costs mount so slowly that they can be difficult to detect. That’s especially true of pot. If she’s using daily, don’t accept her protestations that marijuana has no deleterious effect on her. I don’t care how many cannabis evangelists she can rally to her cause, researchers tell a different story about heavy pot use. Heavy pot use lowers IQ (Meier et al. 2012); it damages memory (Solowij and Battisti 2008); it impairs decision-making (Tamm et al. 2013); it devastates motivation (Treadway et al. 2012; Smirnov and Kiyatkin 2008; Bloomfield et al. 2014); and it increases anxiety (Zvolensky et al. 2008). Finally, no matter what you might have heard, pot is addictive. In part, this is because it lowers the amount of available dopamine in the brain, necessitating its continued use to maintain normal levels (Hirvonen et al. 2011). "

― Shawn T. Smith , The Tactical Guide to Women: How Men Can Manage Risk in Dating and Marriage