How low fat-foods are lying to you

While most of us know we need to eat more fat to feel full and help lose weight, many of us are still buying low-fat foods in the grocery store.

Because low-fat has to mean lower-kilojoule and better for our waistlines, right? Wrong. A new study published in Appetite finds that a majority of low-fat foods don't cut as many calories as you'd expect.

Researchers at the University of Toronto analysed more than 5,700 packaged foods from grocery stores to find that about 61% of products billed as low-fat did not have significantly fewer calories than their full-fat counterparts (in this study, a "significant" drop in calories was defined as a 25% decrease).

How's this possible? Because when companies take fat out of foods, they add in other calorie-dense ingredients like sugar to make up for lost flavour. In fact, many low-fat foods are higher in sugar than the full-fat versions.

But here's the real problem: The myth that lower-fat equals fewer kilojoules is seriously hampering our collective weight-loss efforts. Previous research shows that the mere presence of the word "low-fat" on a food label can make people eat 50% more of that food than if there was no fat claim at all. Since these products seem more virtuous, it's all too easy to feel you can reward yourself with another handful.

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Basically, low-fat foods are a double whammy to your waistline: Not only can they have just as many kilojoules as full-fat versions, they can also prompt you to eat more than you normally would - partly because they have that health halo, but also because they lack filling fat and often have way more sugar. Yep, pretty much the worst weight-loss plan in history.

"The take home message is not to focus on fat messaging, but on the overall healthfulness of the product," says Alyssa Schermel, a co-author of the study and manager of the L'Abbe Laboratory at the University of Toronto. "Read the label, and look for foods higher in fibre and lower in sodium and sugar. Also look for foods that are less processed."

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That means skipping the front-of-package claims altogether. Instead, go straight for the real information about the product—the Nutrition Facts and ingredients list—and you'll make the healthier choice every time.

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