Instant Human
P. J. Rogers' 2007 review calls caffeine the most popular drug in the world. In Canada, at least, it's been very much in the news recently. The Hamilton Spectator (2007) reports that Ahmed El-Sohemy has found a gene that seems to be linked to elevated mood effects from caffeine, at least in men. Different gene phenotypes made a 60% to 20% difference in reporting elevated mood in men, but in women, about 50% reported the mood lift, regardless of gene type. The Ottawa Citizen (2007) suggests that this mood elevation is linked to "caffeine-seeking behaviour", although El-Sohemy did not call this an "addiction." The Edmonton Sun (2007) said that El-Sohemy reported these results at the Advanced Foods and Materials Network Scientific Conference. According to the Ottawa Citizen article, the World Health Organization (WHO) recognizes caffeine dependence but the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) does not.
You know the guy: the one who went through a couple of 2-liter bottles of soda a day, and hates coffee? In my experience, that's pretty much always been a guy. My first experience with it was my father. By college, it was me, although I was more than happy to drink coffee when available. Mountain Dew was just more convenient. However, I don't think that El-Sohemy's work is suggesting that women don't get addicted to caffeine. Because there's no way to accurately rate the degree of the mood lift, it seems more likely that women would demonstrate these caffeine seeking behaviours. Because El-Sohemy's results were presented at a conference, and don't appear to be on his webpage, I can't speculate much further without a lot more coffee.
You know the guy: the one who went through a couple of 2-liter bottles of soda a day, and hates coffee? In my experience, that's pretty much always been a guy. My first experience with it was my father. By college, it was me, although I was more than happy to drink coffee when available. Mountain Dew was just more convenient. However, I don't think that El-Sohemy's work is suggesting that women don't get addicted to caffeine. Because there's no way to accurately rate the degree of the mood lift, it seems more likely that women would demonstrate these caffeine seeking behaviours. Because El-Sohemy's results were presented at a conference, and don't appear to be on his webpage, I can't speculate much further without a lot more coffee.