The Skinny on Fats

Low-fat diets used to be all the rage. Cut butter and reject oil to boost health and manage weight, experts urged. Then came a surprise: a significant new study found that lowfat regimes, though they may spark longings for doughnuts and barbecued ribs, don't lower serious disease risk. What to do with such conflicting advice? Can we find a middle ground, hanker for a bit of cake and eat it, too?

The Heart of the Matter: Fat Type

The prevailing wisdom is that total dietary fat matters less than the types of fat we eat. "There are three kinds of fat in the foods we eat: saturated, polyunsaturated and monounsaturated," explains Doylestown Hospital dietitian Amy Pieczarka. "I recommend keeping saturated fats to a minimum in favor of the more healthful polyunsaturated and monounsaturated fats."

Providing the sizzle on the steak, saturated fat flavors some delicious foods. Bacon and butter certainly look scrumptious, and small quantities can fit into a sound diet - but our arteries are better off skipping the feast. Research has found that saturated fats may promote cancer and inflammation, an emerging risk factor for heart disease. They also tend to raise levels of "bad" low density lipoprotein, or LDL, in our blood streams.

Further, it's wise to steer clear of polyunsaturates that have been "partially hydrogenated" to make them solid at room temperature. "They've been linked to arteriosclerosis and worsening blood cholesterol levels," advises Doylestown Hospital cardiologist George Wiemann, MD. "The government has done an excellent job of making these undesirable ingredients easy to find if consumers take a moment to read the newer food nutrition labels."

On the other hand, non-hydrogenated polyunsaturated and monounsaturated fats - found in nuts, avocados, olive oil, vegetable oils and many more foods - contribute to more healthful blood cholesterol profiles. Pieczarka also advises low-fat versions of animal-source fats like cheese and cow's milk, and small amounts of full strength plant-source foods like natural almond butter and olive oil. Even tropical oils like palm and coconut that had a bad rap earlier appear on the table again. Evidence suggests they may enhance immune powers and have little negative impact on blood cholesterol.

Steering Clear of Trans Fats

For most people, total fat intake can safely provide 30 to 35 percent of daily calories, with 10 percent or less from saturated fats. There's an easy way to tell the difference between the desirable and undesirable: saturated fats come from animals and tend to be solid at room temperature. The other two types come from plants and usually remain liquid at room temperature.

What about radically lowering all fat intake? After all, fat is calorie-dense, packing nine calories into just one gram, and some physicians have famously touted just such a plan for optimum heart health. In most cases, however, moderation is a more successful strategy, even for those trying to lose weight. Fat improves taste and consistency, makes us feel full and stabilizes blood sugar. Drastically lowering fat intake may produce cravings that lead to eating cookies and pies rather than the healthier fats we might have consumed in the first place.

There is one fat, however, that researchers have concluded we're better off avoiding completely, if possible. Created by hydrogenating unsaturated fats, trans fats are re-engineered substances that don't occur naturally. When first introduced, trans fats were thought to be a healthier substitute for saturated fats while also increasing product shelf life. Time and testing have instead implicated trans fats in serious cardiovascular risks. These fats contribute to inflammation, and pack the double wallop of raising "bad" cholesterol levels while concurrently lowering "good" high-density lipoprotein, or HDL, levels.

Eating Sensibly Takes Practice

Sorting out the dietary fat picture may be challenging and time-consuming, but Doylestown Hospital holds classes that help translate the menu. Pieczarka leads "Nutrition for You" and "Nutrition for You 2", during which she discusses dietary fats and healthy nutrition in general. Putting new information to use starts immediately: classes visit a local supermarket to practice reading labels and selecting balanced foods.

Certainly, new eating habits don't happen overnight. But knowing more about what's on the fork makes it easier to follow up that first thoughtful bite with healthier overall nutrition.

Dr. Michael Nicholas is a pediatrician with Kids First Central Bucks practice, Doylestown. Amy Pieczarka, RD, LDN, CCN, CDE, is a nutritionist with Doylestown Hospital. Dr. George Wiemann is a cardiologist with Central Bucks Cardiology.