The SnackWell effect is a phenomenon whereby dieters will eat more low-calorie cookies, such as SnackWells, than they otherwise would for normal cookies.[1][2] Also known as moral license, it is also described as a term for the way people go overboard once they are given a free pass[3] or the tendency of people to overconsume when eating more of low-fat food due to the belief that it is not fattening.[4]
The term, which emerged as a reaction to dietary trends in the 1980s and 1990s,[5] is also used for similar effects in other settings, such as energy consumption, where it is termed the "rebound effect". For example, according to a 2008 study, people with energy-efficient washing machines wash more clothes.[6][7] People with energy-efficient lights leave them on longer, and lose 5–12% of the expected energy savings of 80%.[8]
^"One reason I've suggested is what called the SnackWell's Phenomenon: By giving a free pass to good nutrients, people go there and eat a lot more food. If one SnackWell's is okay because it's low-fat, a whole box is probably better." -- Food writer Michael Pollan in his Otis Lecture at Bates College, Oct. 27, 2008.
