Saucha, or the Niyama that gets translated roughly as purity, asks yogis to consider the baggage they carry around with them and or that they are adding to their lives, whether in the form of bodily impuritities (hence, neti pots), stale thoughts (hello, guilt!), or clutter.
Substance use/abuse can fall into the bucket of things to consider when considering Saucha. And I, for one, have been very resistant to thinking I have any issues here. When we first discussed substance use in teacher training, I dug in my heels, thinking, I've already given everything really bad up, please let me have these bitty little vices. I used to smoke menthol cigarettes (gone), drink hard alcohol (gone), occasional recreational substances in college (gone)--for god's sakes, I don't even eat carbs or sugar anymore!!!"
BUT the big two, coffee and wine, are very much a part of the academic lifestyle and my own. I suspect many of us have done "grocery" shoppings that consist of nothing but these two items. Or maybe you throw in a food so it's not quite so painfully obvious: coffee, pinot grigio, and a gallon of milk--oh really, what's for dinner?
If you are a grad student or faculty at a well-funded institution, the wine and cheese reception is part of the routine, and even if you're not, it may be part of your own routine. I attended graduate school as the cocktail culture inspired by Sex in the City turned into the cocktail culture inspired by Madmen, which meant we all went from drinking vodka to drinking bourbon.
It's not that these pleasures are "bad" in themselves. But it's the routine part that makes me ask what these substances are doing in our lives. If the coffee is there every morning to help get going, and the glass of wine is there every evening to stop going, the routinization of these pleasures might make one ask, what would happen if I got up and unwound on my own? That is to say, purely?
This matter may be of special interest to young women in graduate school or on the tenure track, since alcohol and caffeine affect the overall hormonal balance of the female body (for a great book on this, check out Alisa Vitti's Woman Code http://floliving.com/womancode.html ). But for any academic or young professional, given the likely overstimulation of the adrenals that already comes from living in a state of fight-or-flight due to high stress, why add the baggage of a hit of caffeine to the system?
As I finish writing this, I've finished that second cup of coffee. Ah, well. There's always tomorrow to try for tea.