The Stats on Fats

by Melissa Diane Smith

There are good fats and bad fats, but even the good can be harmful if you don't get the balance right. Here's how to fatten up your diet healthfully.

Fat is often considered nutrition's bad boy, but lumping all fat together as a group isn't fair. There are many types of fats, some hazardous to your health, others essential for wellness. The issue has been confusing, but certain truths remain.

The "bad" fats are still found in red meat, poultry skin and butter and also include the partially hydrogenated vegetable oil found in margarine, nondairy creamers, whipped toppings and other processed foods. The "good" fats are still those found in olive oil, canola oil, some nuts, avocados and cold-water fish such as salmon. The confusion, however, has to do with getting the right fats in the right balance.

Most Americans now realize that the fat-free mindset of years past doesn't work. In fact, a low-fat diet can actually contribute to obesity because many fat-free products are chock-full of sugar -- and empty calories. Plus, the American Heart Association now warns that very-low-fat diets (less than 15 percent of total calories) in the short-term increase triglycerides and lower "good" cholesterol, without yielding additional decreases in "bad" cholesterol.

Meanwhile, too much fat is still a health enemy to much of the American public. Studies continually show that fat (especially trans fatty acids) raises both "good" and "bad" cholesterol, promotes heart disease and is linked to an increased risk of colon, breast, lung and prostate cancer.

So what gives? The truth is, your body does require a moderate intake of fat. Fats form the fatty layer of all your cells and serve as building blocks for hormone-like eicosanoids, which influence virtually every bodily function. They help us absorb vitamins, aid in digestion, provide our bodies' insulation, give us energy, maintain fertility and regulate our metabolism. Fat is a vital nutrient and should not be eliminated from our diets. It's just a matter of getting the right balance.

The Unhealthy Fats
Although most nutritionists advise a fat intake of 20 to 30 percent of total calories, it's important to look beyond the total and pay attention to the type of fats you're consuming -- that is, good versus bad.

Of the bad fats, the big ones to steer clear of are trans fatty acids -- fats that greatly increase the risk of heart attack and compete with healthful omega-3s for vital enzymes and space in your cell membranes. Trans fatty acids are found in processed foods containing partially hydrogenated oils (most commercial snack foods) and in deep-fried foods, shortenings and most margarines. The best way to avoid them is simply to avoid processed foods and eat as many whole, unrefined foods as possible.

The other group to avoid is saturated fats, found in all meat and dairy products, as well as cocoa butter and tropical oils such as coconut and palm. These fats raise total blood cholesterol and clog up your arteries, thereby increasing the risk of cardiovascular disease. To minimize your intake of saturated fats, cut down or stay away from fatty meats and whole milk products, butter and cream.

Remember, your body can get all the fat it needs from good fats, the unsaturated fats and the essential fatty acids. Most people have no need whatsoever for saturated fat.

The Healthy Fats
The good fats list starts with essential fatty acids (EFAs), which are just that -- essential for health. EFAs are fats that are necessary for normal growth and development and cannot be manufactured by the body. There are two families of EFAs: omega-6 polyunsaturated fats and omega-3 fatty acids. The highest amounts of omega-6 are found in common vegetable oils such as corn, sunflower, safflower and cottonseed oils. Omega-3 fatty acids are found primarily in cold-water fish (salmon, trout and tuna), dark, leafy greens, flaxseed and flaxseed oil, and walnuts.

Yet the most important thing to know about EFAs is that a balanced intake of omega-6 and omega-3 fatty acids is needed to promote health. "The ratio of omega-6 to omega-3 fatty acids in the Western diet today is between 10-to-1 and 21-to-1, whereas the diet humans evolved on had a ratio of 1-to-1," explains fat expert Artemis Simopoulos, M.D., co-author of The Omega Plan (HarperCollins) and its new paperback version, The Omega Diet (HarperCollins). "One of the most important medical findings of recent years is that eating a balanced ratio of EFAs brings your diet back in sync with your genes and helps you experience optimal health."

"Omega-3s and omega-6s work differently in the body," she continues. "When they're in balance, they're both very good. When the omega-6s are in excess, they become bad."

For instance, consider that omega-3s produce hormone-like eicosanoids that are anti-inflammatory in nature, whereas omega-6s produce inflammatory eicosanoids. Too many omega-6s in the diet, therefore, can tilt the body's production of eicosanoids in a pro-inflammatory direction, setting the stage for autoimmune diseases such as arthritis. (This means that, on their own, omega-6 polyunsaturates can also be seen as bad fats.)

There's more. Animal studies have found that while omega-6s promote cancer cell proliferation, omega-3s inhibit it (Oncology, 1995, vol. 52). Australian researcher Leonard Storlien has also found that people who have low levels of omega-3 fatty acids and high levels of omega-6s in their muscle cells are more likely to be insulin resistant (a precursor to diabetes) and obese (Lipids, 1996, vol. 31S).

From this and other research, Simopoulos concludes that if you change your diet to develop a good balance between omega-6s and omega-3s, you can reduce the risk of cancer, heart disease, stroke and diabetes, normalize your metabolism to help promote a healthier weight, and fine-tune your immune system. Every cell and system in the body simply works in better harmony, she adds, because they're receiving the balance of EFAs they were designed for.

Unfortunately, developing a better dietary balance between omega-3s and omega-6s isn't easy to do. The sources of omega-3s in the current food supply are scarce to nonexistent, whereas sources of omega-6s are ubiquitous. Therefore, we need to reduce dramatically the amount of omega-6s in our diets as we increase our omega-3s.

The other good fats, in addition to omega-3s, are monounsaturated fats, found in olives, some nuts (macadamias, almonds, peanuts, pecans and cashews), avocados, and olive, nut and canola oils. These fats reduce total blood cholesterol (LDL), without lowering the protective good cholesterol, HDL. In fact, Mediterranean people, who have a diet high in monounsaturated olive oils, have a lower incidence of heart disease and stroke than people of other cultures -- and people of the Mediterranean live longer, too.

A Balancing Act
Getting back to the delicate balance between omega-3s and omega-6s, there are several ways to dramatically lower your omega-6 fatty acid intake. Start by avoiding oils with high omega-6-to-omega-3 ratios, including corn oil, safflower oil, peanut oil, soybean oil, sunflower oil and cottonseed oil. This is the most obvious way to bring your omega-6 intake to a more healthful level.

Make an oil change. Use cold-pressed, extra-virgin olive oil or canola oil in place of omega-6 oils. Olive oil and canola oil are both low in omega-6 fatty acids and rich in monounsaturates -- fatty acids that don't compete with omega-3s in the body. Olive oil is especially healthful because it has antithrombotic properties.

You can also increase your intake of omega-3 fatty acids by eating cold-water fish (such as salmon, trout, tuna, sardines, herring and anchovies) two to three times a week. If you don't like fatty fish, enrich your diet with omega-3-containing fish-oil supplements, preferably ones with added vitamin E to help prevent rancidity.

If you're a vegan who won't eat fish or take omega-3 supplements, use several tablespoons of omega-3-rich flaxseed oil daily. Add it raw to salad dressings and sprinkle it on top of cooked foods. Try grinding flaxseed and adding it to cereal and baked goods or using algae-based omega-3 supplements. Also, add omega-3-rich walnuts to salads and baked goods or eat a few each day as a snack.

If you eat eggs, buy omega-3-enriched ones if you can find them. A number of egg producers are now using a mash that has been enriched with omega-3 fatty acids, either from fish meal or flaxseed. Look for meats from animals that are fed this mixture as well.

Also, seek out meat and milk from free-ranging animals that eat omega-3-rich grass and insects rather than those fattened up on omega-6-rich grains.

Finally, eat your veggies -- specifically, the dark-green, leafy ones. Especially good sources of omega-3 EFAs include romaine lettuce, mesclun mixed greens, arugula, kale, collards, mustard greens and Swiss chard.

*These statements have not been evaluated by the Food and Drug Administration.

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