Fats: The Truth About Good Fats & Bad Fats (cont.)
"I'm also concerned about the mercury that these species of fish can carry for pregnant women," says Kava. She recommends that pregnant women stay away from shark, swordfish, and king mackerel because these bigger species tend to present more of a risk.
If you're not pregnant but still concerned, Kava says small salmon species give the most benefit with the least exposure to mercury.
Animal Fat to Avoid
We've long been told to eat less red meat, but new long-term studies of how eating habits affect actual health measures do not bear out many of the popular myths.
"People want to hear that not eating less red meat will save them, but that is a simplistic notion that doesn't really fit in with modern nutrition science," says Kava. "What the science tells us is that lifestyle changes ? stopping smoking, getting regular exercise, limiting alcohol intake, increasing vegetable intake ? has by far the most pronounced effect in improving a person's health than does cutting out certain food categories."
This does not mean you should eat steak every night. If you're at high risk of heart disease, you should still severely limit your saturated fats. But the newer research does explain why many health organizations no longer try to scare people away from "bad" foods.
For example, says Kendall, "for years, we've encouraged people to eat poultry instead of red meat because it is lower in saturated fat. But when you look at the data on how these foods affect actual blood cholesterol levels, there isn't that much difference."
Rather than avoid meats, nutritionists today say you should simply eat more of the foods proven healthy in long-term studies: fish, vegetables, and fruit. Equally important, exercise, even you just walk briskly 30 minutes a day.
The health message about oils has not changed and is very simple. Stick to olive oil or canola oil.
Olive oil is loaded with monounsaturated fatty acids, which do not raise blood cholesterol levels. It also is a good source of vitamin E and polyphenols, which act as antioxidants, reducing the oxygen-related damage to the vascular system.
Canola oil, on the other hand, has loads of monounsaturated fatty acids in the form of oleic acid. This acid has been shown to reduce blood cholesterol levels, and it may lower LDL, or "bad," cholesterol levels without changing "good" HDL levels. Also, canola oil is high in two essential polyunsaturated fatty acids that our bodies can't make: alpha-linolenic acid and linolenic acid.
Alpha-linolenic acid appears to lower blood triglyceride levels. It also may reduce platelet aggregation and increase blood clotting time, both of which are important to people at risk of heart disease and stroke.
Oils to Avoid
Simply put, avoid vegetable oils that are high in omega-6 fatty acids, such as regular vegetable oil, corn oil, safflower oil, soybean oil, and cottonseed oil.
Until the recently, there really were no healthy spreads. Butter is too high in cholesterol for people who are at risk of heart disease; most margarine is made from trans fatty acids. In the 1980s, some manufacturers put out special, watered-down versions of spreads that had lower overall calorie content, but they tasted like it.
Then came spreads made from olive oil, wood pulp (Benecol) and soybeans (Take Control), which include chemicals that actually help your heart's health.
"Spreads like Benecol, which are made from plant stanol esthers, are lower in trans fat than regular margarine and have been shown to lower the risk of heart disease," says Kendall. They especially help people taking statin drugs to lower their blood cholesterol levels. "But," she adds, "they are more expensive, too, so if you are at risk of heart disease, they may be worth the price."
Kendall suggests doing what the Italians do ? put olive oil on your bread. Or, you could make what she calls "better butter."
Blend one part olive or canola oil with one part butter," Kendall says. It makes a softer spread and dilutes the cholesterol with monounsaturated fats.
Spreads to Avoid
Remember, traditional margarine is a trans fat nightmare. Check the ingredients list and avoid spreads that are made of "hydrogenated" or "partially hydrogenated" oils.
Sources: Patricia Kendall, PhD, RD, professor, Colorado State University Cooperative Extension Office * Ruth Kava, PhD, RD, American Council of Science and Health * Artemis Simopoulos, MD, editor in chief, World Review of Nutrition and Dietetics * The PDR Family Guide to Nutrition & Health.
©1996-2005 WebMD Inc. All rights reserved.
Last Editorial Review: 1/31/2005 5:36:55 AM