There are two sayings making the rounds these days: green is the new black and ___ is the new tobacco.

Green being the new black means environmental awareness has become hip. Rachel Sanderson wrote in a Reuters news story that a market research firm in the U.K. has found that sales of organic, free range or Fairtrade foods are surging because “Green is the new black in ethical Britain.” Fashion writer Suzy Menkes told her International Herald Tribune readers “Why Green is the New Black.” Why? Well, according to Bono of U2, supporting his wife’s Edun line of clothing, “We have got to find ways of making our activism sexy, and fashion is it.” Apparently the venerable Sierra Club agrees, because its magazine portrayed fashion designer Katharine Hamnett as “making green the new black.” Wouldn’t want to go back to wearing “hairy sacks” said Hamnett. Gee, I must have missed that fad. Vanity Fair editor Graydon Carter proclaimed that (guess what?) “Green is the new black” when he introduced the magazine’s green issue last Spring, complete with a star-studded cover by celebrity photographer Annie Leibowitz.

I’ve seen the phrase used as a headline in the magazines Time and Inc., in the Guardian and Sunday Times newspapers, on many websites and blogs, and in materials published by the UK Environment Agency, the Australian City of Sydney, among many others. Somewhere along the line, that phrase gained the status of a cliché.

Then there’s that business about the new tobacco. Unlike the color metaphor, there doesn’t yet seem to be a consensus about what exactly is the new tobacco. Writer Matthew Lynn wrote in Bloomberg News last fall, “There is a very real possibility that aviation is about to become the new tobacco – a product once universally popular that is now socially unacceptable.”

Or maybe it’s junk food. In an effort to fight the rise in childhood obesity, five of the largest snack food producers have said they will start providing more nutritious foods to schools. Responding to the move, Dr. Thomas Robinson, associate professor of pediatrics at the Stanford School of Medicine, likened the problem as “similar to what happened to tobacco over the last several decades.” Along the same lines, the Canadian Heart and Stroke Foundation has warned that “fat is the new tobacco.” A British shareholder activist group argues that “oil is the new tobacco”. Oil companies could find themselves facing large legal suits – similar to those launched against tobacco firms - if they ignore the potential consequences of global warming. Meanwhile, an Australian blogger feels that cell phones could be “the new tobacco.” Then there’s Printing World magazine, which asked “Is offset litho the new tobacco?” (It had something to do with environmental regulations that apparently weren’t being met.)

Aside from an obvious need for creative headline writers and as irritating as clichés are, they herald some strong steps in the right direction. Public opinion polls show that the health and the environment are at the top of people’s list of priorities right now. And although I don’t think this concern involves merely having the right to buy eco bubble bath, I do believe it means that most of us – while we want our governments to stop embarrassing us and get serious about the environment – are willing to make fundamental changes in our lives in order to ensure a future for our children. If it takes clichés to make people trade in their Hummers, eat locally and organically, stop smoking and begin to question how their children are being educated, I’m all for them.