Saturated fat
Credit: John Scott / Getty Images

Although it isn't quite as health-sabotaging as trans fat, saturated fat is no friend to your heart. It raises LDL cholesterol, a key risk factor for cardiovascular disease, heart attacks, and strokes, and since many foods that are high in saturated fat also contain lots of cholesterol, they're a dual stress on the heart. Research shows that too much saturated fat also raises diabetes risk.

Unlike trans fat, which you should avoid altogether, a small amount of saturated fat is OK for your health – which is good, since it's fairly unavoidable. The American Heart Association suggests keeping intake below 7 percent of your total daily calories. If you eat 2,000 calories a day (which is a bit low for most men), that's about 16 grams of saturated fat.

Most of the saturated fat in our diets comes from animal products, such as red meat, skin-on chicken, butter, and milk, as well as foods made with them – cream-based sauces and dressings, ice cream, baked goods, and most anything fried. But certain plant-based oils, namely palm and coconut, also contain a lot of saturated fat. Even if you don't cook with these oils at home, restaurants often do, and they're ubiquitous in packaged snack foods.

To keep your intake low, look to the nutrition label and opt for foods that have either no saturated fat or just a small amount compared to the product's overall fat content and total calories. Eat red meat very sparingly, and always choose the leanest cuts possible — very little marbling with most of the fat around the edges so you can slice it off. Poultry without skin and fish tend to have less saturated fat overall.