Once upon a time, we didn't know anything about fat except that it made foods tastier. We cooked our food in lard or shortening. We spread butter on our breakfast toast and plopped sour cream on our baked potatoes. Farmers bred their animals to produce milk with high butterfat content and meat marbled with fat because that was what most people wanted to eat. But ever since word got out that diets high in fat are related to heart disease, things have become more complicated. Experts tell us there are several different kinds of fat, some of them worse for us than others. In addition to saturated, monounsaturated and polyunsaturated fats, there are triglycerides, trans fatty acids, and omega 3 and omega 6 fatty acids. Most people have learned something about cholesterol, and many of us have been to the doctor for a blood test to learn our cholesterol number. Now, however, it turns out that there's more than one kind of cholesterol, too. Almost every day there are newspaper reports of new studies or recommendations about what to eat or what not to eat: Lard is bad, olive oil is good, margarine is better for you than butter then again, maybe it's not. Amid the welter of confusing terms and conflicting details, consumers are often baffled about how to improve their diets. FDA recently issued new regulations that will enable consumers to see clearly on a food product's label how much and what kind of fat the product contains. See A Little Lite Reading in the June 1993 FDA Consumer. Understanding the terms used to discuss fat is crucial if you want to make sure your diet is within recommended guidelines. Fats and Fatty Acids Fats are a group of chemical compounds that contain fatty acids. Energy is stored in the body mostly in the form of fat. Fat is needed in the diet to supply essential fatty acids, substances essential for growth but not produced by the body itself. There are three main types of fatty acids: saturated, monounsaturated and polyunsaturated. All fatty acids are molecules composed mostly of carbon and hydrogen atoms. A saturated fatty acid has the maximum possible number of hydrogen atoms attached to every carbon atom. It is therefore said to be saturated with hydrogen atoms. Cholesterol Cholesterol is sort of a cousin of fat. Both fat and cholesterol belong to a larger family of chemical compounds called lipids. All the cholesterol the body needs is made by the liver. It is used to build cell membranes and brain and nerve tissues. Cholesterol also helps the body produce steroid hormones needed for body regulation, including processing food, and bile acids needed for digestion. People don't need to consume dietary cholesterol because the body can make enough cholesterol for its needs. But the typical U.S. diet contains substantial amounts of cholesterol, found in foods such as egg yolks, liver, meat, some shellfish, and whole- milk dairy products. Only foods of animal origin contain cholesterol. Government Advice Dietary guidelines endorsed by the U.S. Department of Agriculture and the U.S. Department of Health and Human Services advise consumers to: Reduce total dietary fat intake to 30 percent or less of total calories. Reduce saturated fat intake to less than 10 percent of calories. Reduce cholesterol intake to less than 300 milligrams daily. |
