SAVOR GOOD FATS
You can protect your heart by filling up on fats that boost good cholesterol, including monounsaturated fats (found in olive oil, canola oil, and nuts) and polyunsaturated fats (found in fish). Cut saturated fats (found in meat and cheese) to 7 percent of calories or less, and keep transfats (found in many baked goods and fast foods) to less than 1 percent of calories. So, for an 1800 calorie-a-day diet, you want less than 14 grams saturated fat and less than 2 grams transfats (a McDonald's Quarter Pounder with cheese has 12 grams saturated fat and 1.5 grams transfats).
DON'T GO TOO LOW
Eating 30 to 35 percent of calories from fat may be better than eating a low 20 or 25 percent from fat. Recent research found that women who tried 20-percent-fat diets didn't lower their risk of heart disease or breast cancer. Other studies have found that when people eat moderate levels of healthy fat, they also tend to eat more vegetables, says McManus. Some said they ate more salad because the full-fat dressing (made with olive or canola oil) made it taste better; others ate vegetables because they could roast them in olive oil.
KEEP THE MAYO
Regular mayonnaise has less artery-clogging saturated fat than butter (less than 2 grams per tablespoon versus 7 grams), and twice as many hearthealthy fats (8 grams per tablespoon versus 4). Caloriewise, both are exactly the same. Mayo is a little healthier because it's usually made with soybean or canola oil instead of animal fat, says Douglas Balentine, Ph.D., director of nutrition sciences at Unilever North America.
KNOW THE FACTS ON CHEESE
Cheese, not meat, is the leading source of saturated fat in the American diet. Just three one-inch cubes of cheese total 18 grams of saturated fat—that's an entire day's allowance for some people. Think of cheese like chocolate: fine in moderation.