All fats are combinations of fatty acids. Fatty acids are produced by the hydrolysis of the ester linkages in a fat or biological oil (both of which are triglycerides), with the removal of glycerol. Nutritionists characterize a dietary fat or oil as saturated, monounsaturated, or polyunsaturated depending on which fatty acids make up the largest portion of the fat or oil:

• Foods such as butter, which are high in saturated fatty acids, are solid at room temperature and get harder when chilled.
  
• Foods such as olive oil, which are high in monounsaturated fatty acids, are liquid at room temperature; they get thicker when chilled.
  
• Foods such as corn oil, which are high in polyunsaturated fatty acids, are liquid at room temperature and stay liquid when chilled.

So how come margarine, which is composed primarily of unsaturated fatty acids, is solid? Because its fatty acids have been artificially saturated with extra hydrogen atoms. This process, called hydrogenation, turns an oil, such as corn oil, into a solid fat - margarine. Hydrogenated fats are sometimes called trans fatty acids, but no matter what you call them, these fatty acids raise - rather than lower - cholesterol levels. As a result, these days most margarines boast “no trans fats” right on the label. I know your mother told you not to toot your own horn, but these guys have earned the right. So when you’re shopping, pick them.

Carbohydrate foods form the base for a healthful, low cholesterol diet. In 2000, the U.S. Department of Agriculture and the U.S. Department of Health and Human Services recommended that approximately 55 to 60 percent of your daily food energy should come from foods such as grains (particularly whole grains) and fruits and vegetables that are high in complex carbohydrates.

Carbohydrates are nutrient molecules built of units of sugar. As the sidebar, “Sweet talk: Simple versus complex,” explains, the more sugar units a carbohydrate molecule contains, the more complex the carbohydrate is. When it comes to controlling your cholesterol, the most important complex carbohydrate (and the most important carbohydrate, period) is dietary fiber.

The word dietary is stuck in front of fiber to make sure you understand that this fiber, which comes from food, is different from the natural and synthetic fibers, such as silk, cotton, wool, or nylon, used in fabrics. Dietary fiber is a complex carbohydrate, but it isn’t just any old complex carb like, oh, starch. Your body can digest starch, but it can’t digest dietary fiber because the human gut doesn’t have digestive enzymes strong enough to dissolve the chemical bonds holding the fiber molecule’s sugar units together. As a result, you don’t get any calories or other nutrients from dietary fiber. But that doesn’t mean it’s worthless. On the contrary, dietary fiber is very useful in helping to control cholesterol. Foods contain two kinds of dietary fiber - insoluble dietary fiber and soluble dietary fiber. Both are important to a healthful diet, but only one helps control cholesterol.

In the memorable words of the New England Journal of Medicine, insoluble dietary fiber acts like a “colonic broom,” stimulating intestinal contractions that move solid waste through your digestive tract. By moving food quickly through your intestines, insoluble dietary fiber may help prevent or relieve digestive disorders such as constipation or diverticulosis (infection caused by food getting stuck in small pouches in the wall of your colon). Insoluble dietary fiber has no effect on your cholesterol. To bring cholesterol into the picture, you have to turn to the second kind of dietary fiber, the soluble variety.

Pectins and gums are soluble dietary fiber. Both dissolve in your stomach forming gels that look like the stuff made from packages of fruit gelatin. This gel is believed to sop up cholesterol and slide it out of your body, thus reducing the amount of cholesterol particles that are left to wander around your blood vessels and make trouble. You find pectins in the fruit-part of fruits (apples are a particularly good source). Gums are most plentiful in legumes (beans and peas) and grains such as oatmeal and barley.

There’s no dietary fiber in any food from animals. No fiber in meat. No fiber in fish. No fiber in chicken. No fiber in milk. No fiber in eggs. See why plant foods are so important in a cholesterol-lowering diet?

Remember Goldilocks, the gal who found three bowls of porridge, one too hot, one too cold, and one just right? Well, dietary fiber is something like that. The U.S. Department of Agriculture says that the average American woman gets about 12 grams of fiber a day from food; the average American man gets about 17 grams. These amounts are well below the current recommendations of 25 grams a day for a woman and 38 grams a day for a man. But if you decide to stuff yourself with dietary fiber to make up for years and years of low-fiber noshing, the result may be gastric distress - an unmistakable body protest in the form of intestinal gas or diarrhea. In extreme cases, loading up on dietary fiber but failing to drink sufficient amounts of liquid to swish the fiber through your gut can lead to an intestinal obstruction. Yipes! So remember the Golden, I mean, the Goldilocks Rule: Not too little. Not too much. Just right. And build up your fiber intake gradually, please. Your tummy, as well as your cholesterol, will thank you.

If you take care of the fat and fiber, the fat energy will take care of itself. Fat is high in energy; carbohydrate foods are relatively low in fat and thus relatively low in energy. Dietary fiber has no energy at all. If you limit your fats and increase your dietary fiber and complex carbs, you automatically cut food energy and lose weight.

Nutrition gurus like to say that there’s no such thing as a bad food, only a less effective food plan. However - and it’s a big however - some foods are more effective than others when it comes to lowering your cholesterol. To point you in the right direction, article cholesterol lowering foods lays out a list of specific foods that help reduce cholesterol levels and the risk of heart attack. Foods that can increase your cholesterol and your risk are listed in high cholesterol foods article.