A government-appointed group of top nutrition experts, assigned to lay the scientific groundwork for a new version of the nation's dietary guidelines, decided earlier this year to collect data on the environmental implication of different food choices.

Congress now has slapped them down.

Retailers look to sell sustainability of food

Jan 17, 2014
Abbie Fentress Swanson/Harvest Public Media

Consumers are increasingly willing to pay more for foods they believe were sustainably produced, like free-range chicken, fair-trade coffee and pesticide-free wine. But what does “sustainable” actually mean?