Why Low Fat Diet Foods Can Pile On The Pounds

By Kirsten Whittaker

A new study finds that choosing low fat diet foods ("light" or "lite" foods) over the real, full-fat option might just have you packing on the pounds... all the while thinking you're doing right by your body. That's so unfair.

These findings are a direct challenge to the idea that a food made with some type of fat substitute will help you lose weight. In fact, the opposite is likely true.

To prove it, researchers fed mice a particular brand of potato chips every day; one group of mice following diet low in fat, the other half diet high in fat.

Mice following the high fat diet, who devoured the "light" variety chips they were fed on some days, were found to gain more weight compared with the mice who ate the regular, full fat, high calorie variety all the time. The light chips are made with a synthetic fat substitute, which passes undigested through the body so that it has zero calories.

What's worse, when the chips were no longer offered, the fat mice could not budge the extra weight. So the "light" chips not only didn't prevent them from gaining weight, but the food appeared to cause problems with metabolism and made the mice hold onto extra fat, even once they stopped crunching on those chips.

It appears that fat substitutes might just interfere with the ability of the body to regulate food intake... lead to overeating and thus to weight gain.

Why should a fat substitute be confusing for the body? Anything with sweet or fatty is a trigger that signals a high volume of calories are coming, bringing on natural responses like salivation, hormone secretions and reactions from the metabolism. When the body is under the expectation it is about to get a large amount of calories, but gets fooled by the fat substitute, it can cause problems.

It would seem that a healthy diet that's naturally low in fats and calories, may well be better in the long run for weight loss or maintenance than one with foods that include fat substitutes. While many will question how findings in mice apply to people, researchers know that our bodily reactions to food are very similar.

Other studies have shown that when eating "healthy" or "light" dieters tend to consume a whole lot more than if we'd started with the full-fat option initially. That can't be good.

The good news, if there is any, is that the mice on the low-fat diet didn't gain a lot of weight from either of the potato chip varieties they were eating. When they were put on to a high fat diet however, the subjects that had eating both the "light" or regular varieties ate larger volumes of food and thus gained more body fat and weight than the mice that had only eaten the high calorie variety.

Mother Nature is very wise. Mess with our bodies natural hunger cues and you'll end up doing a lot more harm than you think. Relying on low fat diet foods, artificial sweeteners or fat substitutes to do the job or restricting calories sets you up to fail... and buy more "light" foods.