The Lure of Low-Fat Labels

ByABC News
December 8, 2006, 9:01 PM

Dec. 11, 2006— -- Stocking up on low-fat snacks could actually make you fat, suggests a new study published in the Journal of Marketing Research.

Cornell University researchers found that people consume more calories when they eat low-fat snacks than when they eat the regular versions -- especially if these people are overweight.

And while information on proper serving size seemed to slow down the snacking urges of normal weight people, a companion study found that overweight people ate more low-fat snacks regardless of the serving size on the label.

The study found that people tend to underestimate the amount of calories in low-fat snacks and overestimate how much of these snacks they think they can get away with eating.

It's an easy mistake to make. Participants in the study expected the low-fat snacks they ate were 20 to 25 percent lower in calories, so they thought they could eat more.

Like many folks, they mistakenly thought that "low-fat" is equal to "low-calorie."

In reality, the low-fat snacks used in the study were not that much lower in calories than the regular versions -- which is usually the case for other low-fat snacks on supermarket shelves.

True, the low-fat snacks had 59 percent less fat. But they only contained 15 percent fewer calories per serving.

So the low-fat "halo" led overweight participants in the study to load up on these snacks, consuming 90 more calories when a snack had "low-fat" on the label rather than a regular label. That was about a 50 percent increase.

Normal weight people in the study also seemed enticed by "low-fat," but they didn't do quite as much damage. They ate 30 more calories per snacking session, on average.

But for both groups, the results show that these "innocent" low-fat snacks actually contributed more calories to the diet because more were eaten.

The authors of the studies conclude that low-fat labels give people the mental permission to eat more. People appear to feel less guilty about how much they eat when they reach for a low-fat snack, which translates into eating more.