Low-fat foods may not equal weight loss

WEST LAFAYETTE, Ind. (WLFI) - A Purdue study showed people who want to lose weight might also want to lose the fat substitutes in their diets. Eating low-fat foods to lose weight might seem like common sense, but a recent study shows fat substitutes could make you, well, fat. It's a finding some on Purdue's campus said makes them think twice about eating low-fat foods.

"There's always moms or whatever trying to lose weight by it and now it's actually doing the opposite thing for them. I'm surprised by it,” said Connor Tuzi.

"I never really thought that something advertised as low fat would do the reverse effects to you,” said Ethan Flint.

Rats ate either regular high fat potato chips or fat-free chips with Olestra, a synthetic fat with no calories. The rats that ate the fat-free Pringles got a surprise when they got on the scale.

"They actually ended up gaining more weight,” said Purdue Professor of Psychological Sciences Susan Swithers.

Swithers, who did the study, believes the weight gain happened because fat substitutes confuse the body. The taste of food is a cue to how many calories are being eaten. The way the body controls food in-take becomes ineffective when the calories don't actually end up in the body.

"After an experience with Olestra, that cue no longer predicts a lot of calories all the time so we might over eat the next time we get fat that has calories,” she explained.

Rats and humans have obvious differences but Swithers believes the lesson for any animal may be that replacing fats may not be the best weight loss strategy.

"Instead, reducing portion sizes and paying attention to how many calories we're consuming is a better way to go,” said Swithers.

Some people said full fat foods have another advantage:

"It tastes better,” said Laura Creemer who never eats low-fat foods.

Giving some people another reason to eat the fatty foods they love.

A previous study done by the same professor showed artificial sweeteners also caused rats to gain more weight.