• by Sarah Mahoney  @mahoney_sarah, September 14, 2011

While it probably won't be enough to shed its "Whole Paycheck" reputation, Whole Foods Market is going on a price offensive. First, its offer of $20 worth of groceries for $10 has become the fastest-selling coupon on LivingSocial. And second, it's publicizing consumer research that claims it is actually cheaper than other supermarkets.

The LivingSocial program, the first national grocery coupon ever offered by the deal site, didn't just sell well, it sold fast. At its peak, consumers were buying about 80 coupons per second, Brendan P. Lewis, a spokesperson for the Washington D.C.-based LivingSocial, tells Marketing Daily. (While that's its fastest-selling coupon, it's not the best-selling, a distinction that still goes to Amazon, which sold 1.3 million coupons back in January he says.) And Whole Foods is also donating a portion of the proceeds toward its Whole Kids Foundation and antiobesity programs, another first for a national LivingSocial promotion.

Separately, Whole Foods, based in Austin, Tex., says it isn't just competitive with other national food chains, but that it's actually cheaper: It released a competitive pricing study showing that a basket of popular grocery items costs $5.38 less at Whole Foods Market than at other supermarkets. (The sample basket included non-sale prices for eggs, romaine lettuce, soymilk, yogurt, peanut butter, pasta sauce, and frozen fruit.)