Are Low-Fat Foods Making You Fat?

While swapping out fat sounds like it can only be a good thing, experts say that’s not necessarily so. When food manufacturers cut the fat, they often replace it with extra sugar to make the food more palatable, particularly in low-fat cookies and other baked goods, according to Bauer. They also may add thickening agents, such as carrageenan and various gums, to mimic the texture of fat.

“Fat is a very addictive and satisfying component of food, and you’re replacing it with another very addictive food—sugar,” says Kristin Kirkpatrick, R.D., wellness manager for Cleveland Clinic's Lifestyle 180 program and YouBeauty Nutrition Advisor. The trouble is, sugar doesn’t provide the same level of satiety as fat—that satisfaction you get after eating a meal—which can leave you searching for another fix and vulnerable to eating more later on. “We need fat in our diets,” says Kirkpatrick. “Fat is extremely satisfying and keeps us fuller for longer, while sugar tends to spike our blood sugar, followed by a very big drop, and causes us to feel hungrier—and look for more sugar.”

While that doesn’t mean you have free rein to down that double cheeseburger and chase it with a pint of Ben & Jerry’s, it does mean that there’s room for some fat in your diet—and that low-fat and fat-free foods aren’t always the healthiest option.

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To keep your portions and calories in check, follow these smart steps:

* When your sweet tooth is demanding some serious attention, rather than inhaling half of a bag of fat-free cookies, go for a real chocolate chip cookie instead—just be sure to stop at one. “If you want to have a sweet every once in a while, don’t beat yourself up about it,” says Kirkpatrick.

* Never eat straight out of the package. Whether you’re indulging in low-fat or full-fat snack foods, check the serving size on the nutrition facts panel, take out one serving’s worth, put the package away and then enjoy your snack, suggests Bauer.

* If you’re eating a low-fat food, such as a frozen yogurt, but aren’t sure how many calories it contains, give your best estimate—and then double it. “You’ll be more accurate,” says Wansink.

But not all low-fat and fat-free foods should be banished like a loser on “Survivor.” A good example is dairy. “Full-fat dairy products such as whole milk are high in saturated fat, the type of fat that raises LDL ‘bad’ cholesterol levels and promotes inflammation, so you definitely want to choose low-fat or fat-free dairy products to minimize the saturated fat in your diet,” says Bauer. Go for skim or one-percent milk, and nonfat or low-fat yogurt.

When it comes to cheese, choose reduced-fat cheeses made with two-percent milk. “Without some fat, the cheese has a chewy or rubbery rather than creamy texture and won’t melt well,” says Bauer. “But choosing cheeses made with two-percent milk instead of the typical whole milk will still save you a significant amount of calories and fat.”

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