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The Bacon in Your BLT

What's in it: Saturated fat

The science: HDL, or "good" cholesterol, has an anti-inflammatory effect within your arteries. Saturated fat makes HDL less effective at that job, according to a small study in the Journal of the American Academy of Cardiology. Fourteen adults ate meals with the same number of calories but differing amounts of saturated and polyunsaturated fats. (The meal was a slice of carrot cake and a milkshake, in case you were curious.) Anti-inflammatory activity was hindered after the saturated-fat meal, while polyunsaturated fats boosted that activity. In another study, eating less saturated fat lowered participant's levels of substances that trigger inflammation.

One more thing: In addition to processed meats, saturated fat is also in lamb, chicken with the skin still on, beef, cheese, cakes, cookies and ice cream. You don't have to cut these foods out entirely, but you can follow the American Heart Association's advice of limiting calories from saturated fat to less than 7 percent of your daily calories. If you eat 2,000 calories per day, that's about 16 grams of saturated fat.