Stop worrying about fat

When making choices about what food to eat, keep your eye on the big picture. Favor healthy fats instead of avoiding all fats.

Fat seems to always top the list of things that are "bad" for you. But for good overall health and to lower risk of heart disease, cancer, or even obesity, scrupulously counting how much fat you consume is not a helpful strategy. "Focusing only on grams of total fat, whether in a food or in your diet, can lead a person to make poor decisions," says Dr. Dariush Mozaffarian, an associate professor of medicine at Harvard-affiliated Brigham and Women's Hospital.

High on the list of bad food decisions is eating processed foods and fast foods that bill themselves as low-fat, reduced-fat, or fat-free. Lowering total fat alone does not make a food healthier, and many of these products are high in salt, sugar, and refined carbohydrates. For example, low-fat deli sandwiches are loaded with salt and refined carbohydrates and low-fat frozen yogurt or low-fat muffins may contain a lot of refined carbohydrates, such as white flour and sugar.

More important, avoiding all fats means you miss out on the benefits of healthy fats, like those in nuts, fish, avocados, and olive oil. Recent research suggests that extra-virgin
olive oil is particularly beneficial. "A common mistake is to avoid and replace foods that have healthy fats and that are good for you with low-fat processed and packaged foods that are high in refined carbohydrates and sodium," Dr. Mozaffarian says.

Instead of obsessing about fats, focus on healthy foods. "Eat fruits, vegetables, nuts, fish, vegetable oils, whole grains, and modest portions of dairy," Dr. Mozaffarian advises. "Avoid processed meats, sugary beverages, and foods high in refined grains, starches, sugars, and salt."

Saturated fat and the heart

One reason we tend to be preoccupied with fat is its connection with heart disease. Fat—particularly saturated fat from animal foods—is bad for the
heart, right?

Dr. Mozaffarian and his colleagues have taken a hard look at the scientific evidence that consuming a lot of saturated fat leads to heart disease. "The association is not as firmly established as many people believe," he says. "The evidence does not support a major benefit of focusing on saturated fat alone, without considering the overall food itself and what is eaten instead."

The take-home message: Don't avoid a food simply because it contains some saturated fat, and don't think a food is healthy only because it is saturated fat-free. That means a fast-food sandwich that bills itself as "low-fat" may still be a Trojan horse for heart disease if it contains processed or cured meats, which research has consistently linked to heart disease.

What's good about fat?

More important than total fat intake is what kind of fats you eat and from which foods. Unsaturated fats, for example, are healthier choices than foods rich in saturated fat from animal sources, foods containing partially hydrogenated oils and trans fat, and foods high in refined carbohydrates, starches, and sugars.

Unsaturated fats exist in two forms: polyunsaturated and monounsaturated. You can obtain polyunsaturated fats from salmon and other fatty fish as well as corn, soybean, safflower, and cottonseed oils. Rich sources of monounsaturated fats include olives and olive oil, canola and peanut oils, and most nuts.

The most unhealthy type of fat is trans fat from partially hydrogenated oils. Trans fats form when vegetable oils are processed to make them more solid at room temperature. You'll find trans fats in many baked goods (such as donuts, muffins, and pie crusts), snack foods (crackers, popcorn),
and some fried foods. No amount of trans fat from partially hydrogenated oils is considered healthy.

What to eat

When we prepare meals, we don't reach for fats—we reach for foods. This is
one key to solving the dietary fat
dilemma. "Focus on foods that have been shown to be good for health, not on trying to make your diet higher or lower in any one type of nutrient," Dr. Mozaffarian says.

The Mediterranean style of eating, increasingly in vogue, provides a diet based on healthy foods. Among its hallmarks:

• most daily calories from fruits, vegetables, beans, nuts, and whole grains

• generous amounts of extra-virgin olive oil for cooking and dressing salads

• moderate consumption of eggs, fish, and poultry, but very little red meat

• moderate consumption of dairy, including cheese and yogurt

• for those who drink alcohol, moderate portions of wine.

Eating Mediterranean style delivers dietary fats that are largely of the healthy type. Recent research suggests that it improves many disease risk factors, including blood pressure and blood cholesterol levels. Abundant fruits, vegetables, and whole grains mean this diet is also filling and fiber-rich, providing satisfying meals that can help you maintain a healthy weight. Most of the carbohydrates are from whole, not processed, foods such as fruits, vegetables, and whole grains.

Beyond the low-fat era

The bottom line about fats is that it matters what types of fats you eat and, more importantly, the types of foods you eat. If you're eating in fast-food restaurants and focusing on checking labels of packaged and prepared foods in the supermarket, you are heading in the wrong direction. Instead, go to the fresh foods sections, where you can buy fruits, vegetables, nuts, and fish. The foods there have fat, but it is the kind you need for good health.