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Medical Myths: All fats are bad



"Fat is bad." That short sentence doesn't sound like much of a stretch. After all, we are in the middle of a long and highly publicized obesity epidemic. Any time you read or see anything about medical science — whether it's heart disease or diabetes or joint health — one of the complicating factors is always excess weight, which we instinctively associate with the word "fat." That's why, when shopping at the grocery store, we've been trained to look for the words "fat-free" on the front of the package.

fatty foods

But if you look at the back of the package, you'll see that it's not quite that simple — there is more than just one kind of fat. And according to Jill Reece, RD, clinical bariatric dietitian at Tufts Medical Center, there are some fats that are actually good for us.

"The myth that all fats are bad for us stems back from the early 1970s, when there was a suggested restriction on fat. A low-fat diet gained traction by the 1980s and by the 1990s it became a focus for Americans says Reece. "Fat does typically have more calories than carbs or protein, but there was never much discussion in terms of type of fat — saturated or unsaturated fats."

Reece says that it's long been known among dietitians and others in the medical community that monounsaturated and polyunsaturated are "good fats." They are typically found in plant and animal foods, like fatty fish, oils, nuts and seeds. These fats not only help lower your bad cholesterol (LDL), they also tend to contain significant amounts of omega-3 and omega-6 fatty acids, which can lower your blood pressure, reduce the build-up of plaque in your arteries, control blood sugar, and reduce the risk of diabetes. Healthy fats, in general, are also a key source of energy throughout your day.

The fats to avoid are the saturated fats found in fried foods, baked goods, and things like pizza. These have all the adverse impacts we generally associate with the f-word, like weight gain, high cholesterol, and increased risk of heart disease and stroke.

Reece says the key is balance. She typically encourages people to devote 30% to 35% of their diets to fat, 20-25% to protein, and the rest to carbohydrates. Opt for salmon, avocados, nuts, seeds, and liquid oils instead of butter and animal meats with visible fats.

And Reece always urges that, when shopping, we always check the nutrition facts and ingredients on the back of the packaging to know exactly what you're putting into your body.

"Looking at the types of fats might lead to a better overall health profile," she says.