Editors at a recent Los Angeles food conference agreed that cutting down on fats was the No. 1 health recommendation in the stories they write. But the types of fat and how they affect the diet are still puzzling to readers.
The most recent introduction of new oil on the market--canola oil, the most unsaturated of polyunsaturated oils--provides the perfect opportunity to talk about oils, what they are, their role in the diet and how they measure up against one another.
For the Record
Los Angeles Times Sunday March 19, 1989 Home Edition Food Part 10 Page 18 Column 3 Food Desk 3 inches; 88 words Type of Material: Correction
In the Rose Dosti story on oils and fats in the March 16 Food Section, we inadvertently gave out toll-free telephone numbers for the American Heart Assn. and the American Dietetic Assn. In lieu of telephone calls, both organizations prefer that the public write for additional information and send self-addressed stamped envelopes.
To contact the American Heart Assn. contact the local affiliate office or write to: American Heart Assn., National Center, 7320 Greenville Ave., Dallas, Texas 75231-9986, or American Dietetic Assn., Nutrition Resources Department, 216 W. Jackson Blvd., Suite 800, Chicago, Ill., 60606-6695.
The key to the fat issue is its affect on health and its direct link to heart disease.
Since 1958 at least 17 health agencies, including the American Heart Assn. and the National Cancer Institute have called for sweeping changes in the American diet in an effort to reduce heart disease, which claims 500,000 Americans each year.
Most recently the U.S. Surgeon General C. Everett Koop urged Americans to improve their dietary health by reducing their consumption of fat, especially saturated fat and cholesterol.
In his report he urged consumers to reduce total fat intake, especially saturated fat, and to choose foods low in fat and saturated fat. Further, he stated, "Among vegetable fats, those that are more unsaturated are better choices."
Today Americans consume an average of 37% in fat, more than the upper limit of 30%, and 13% from saturated fat recommended by the American Heart Assn. and the American Cancer Society. Less than 10% saturated fat is urged, however.
Despite a 6% drop in fat consumption in the last six years, fat consumption in the United States is above that consumed by Mediterranean countries, Japan and China where coronary heart disease rates are much lower than those in the United States. Saturated fat has been linked to coronary heart disease, claiming an average of 1,370 people per day. Excessive levels of dietary cholesterol and saturated fat have been shown to significantly increase blood cholesterol levels.
A 1988 survey at the De Bakey Heart Center at Baylor College of Medicine in Houston showed that 56% of 18,000 dietitians and practitioners agreed that saturated fat--and not dietary cholesterol--is the biggest culprit in raising serum cholesterol in the blood, according to Debbie L. Tindle, a registered dietitian and director of the weight management program at Colima Internal Medical Group, Inc., in Whittier.
Where is all the fat coming from?
It comes from oils and fats used in baking and cooking.
Oils that are most unsaturated are best choices, according to health experts.
However, selecting the proper oil for cooking and salads is not enough. "Oils hidden in processed foods pose a problem because the consumer must interpret the label in order to determine the percentage of fat contained in the product," said Tindle.
The label contains information not only on the percentage of grams fat, but also the type of fat.
Do you know your oils?
We have included a chart showing the percentage of saturated fat for each oil commonly available. Note that canola oil, the newest oil on the market is the least saturated.
All fats are made up of varying combinations of saturated, mono-unsaturated and polyunsaturated fatty acids, but one type of fatty acid usually predominates. The more saturated the fat, the fewer the double bonds and the more hydrogen (firmness at room temperature) they contain.
Two Unsaturated Types
There are two types of unsaturated fats: polyunsaturated and mono-unsaturated fats. Polyunsaturated fats can actually help lower blood cholesterol, thus reducing risk of developing heart disease. Recent studies indicate that mono-unsaturated fats can also help reduce blood cholesterol levels, in particular, the harmful LDL cholesterol (low-density lipoproteins) without affecting the protective high-density lipoproteins (HDL), which are packages of fatty protein. Medical experts believe the cholesterol carried by LDLs is more likely to adhere to artery walls, while HDLs helps remove cholesterol from the body.)
Cholesterol is a soft, waxy substance which is present in all parts of the body, including the brain, nerves, muscles and heart. However, if too much cholesterol circulates in the blood, it can build up on the inside of artery walls, especially in the arteries leading to the heart. This can slow the flow of blood and greatly increase the risk of a heart attack. Before any cholesterol can travel through the bloodstream, it must be attached to lipoproteins.
Polyunsaturated fatty acids are fats that have two or more double bonds--less hydrogenation and are more liquid at room temperature. Corn, sunflower, safflower and soy oils are good examples.
Mono-unsaturated fatty acids contain one double bond, meaning that they have a neutral effect on serum cholesterol and coronary heart disease risk. Recent preliminary studies indicate that monounsaturates may have a favorable effect on good health. Peanut and olive oil are examples of mono-unsaturated oils.