There are three main types of fats in food, and they affect blood cholesterol in different ways:
Saturated fat - Found in red meats and red meat products, such as beef, pork, and lamb, as well as dairy products; in tropical oils such as palm oil, palm kernel oil, and coconut oil; and in vegetables oils that have been chemically changed to make them solid at room temperature (a process called hydrogenation).
Monounsaturated fats - Found in plant oils such as olive, canola, and peanut oil. Monounsaturated fats are liquid at room temperature but harden in the refrigerator.
Polyunsaturated fats - Found in plant oils such as safflower, sunflower, corn, or soybean oil. Fish, especially cold-water fish, contain a special type of polyunsaturated fat called omega-3 fat that may help protect against heart disease by slowing blood clotting. Polyunsaturated fats remain liquid even at colder temperatures.
Which Fats Raise Blood Cholesterol Levels?
Although all fats are concentrated sources of calories and can contribute to weight gain (and thus, high blood cholesterol levels), saturated fat is the most harmful type of fat.
Saturated fat is the main cause of high blood cholesterol levels. When you eat too much saturated fat, your body reacts by making more cholesterol than it needs, and the surplus ends up in your blood.
Which Fats Lower Blood Cholesterol Levels?
Both monounsaturated and polyunsaturated fats help lower blood cholesterol levels by helping your body get rid of newly-formed cholesterol. But these fats should replace some of the saturated fat in your diet - not be used in addition to saturated fat.
However, all fats, even if they are monounsaturated and polyunsaturated, are high in calories. Fat contains nine calories per gram (a measure of weight). In comparison, protein and carbohydrates only contain four calories per gram. Using a large amount of monounsaturated or polyunsaturated fats to lower cholesterol will backfire, because the extra calories will make you gain weight, which will push up your cholesterol levels.
To replace saturated fat with monounsaturated and polyunsaturated fat:
Use margarine and spreads made from these oils instead of butter. (If a food lists a hydrogenated oil as the first or second ingredient, it is still high in saturated fat.)
Use liquid vegetable oils in cooking.
Use non-stick vegetable oil spray to coat cooking pans.
Read the ingredient labels and choose foods made with vegetable oils rather than hydrogenated vegetable oils, lard, butter, or tropical oils such as palm or coconut oil.
How Does Dietary Cholesterol Affect Blood Cholesterol?
Although a diet high in saturated fat is the main cause of high blood cholesterol levels, high cholesterol in the diet can also raise blood cholesterol levels. And usually the effect is twice as bad, because foods high in cholesterol are usually high in saturated fat.
Which Foods Contain Cholesterol?
Only animal foods contain cholesterol - plant foods do not contain cholesterol. In animals, as in humans, cholesterol is a part of all cells and serves many vital functions. Therefore, foods of animal origin - such as meat, poultry, fish, eggs, or milk - all contain some cholesterol.
Generally, foods high in animal fat are also high in cholesterol. Two exceptions to this generalization are liver and eggs, which are not high in fat but are high in cholesterol.
Liver contains large amounts of cholesterol because the liver is the body organ that makes cholesterol.
Eggs contain large amounts of cholesterol because they contain the nutrients and other substances to support a growing embryo (eggs also contain a very high quality of protein and are rich in vitamins and minerals).
The table below shows the approximate cholesterol content of some common animal-based foods.
Milligrams of cholesterol
3 ounces of liver
one large egg
3 ounces of lean red meat
3 ounces skinless poultry
3 ounces fish
one cup whole milk
one ounce cheese
1 teaspoon butter
one cup skim milk
How Much Cholesterol Is Too Much?
The American Heart Association and other health experts recommend that you eat less than 300 milligrams of cholesterol daily.
The average American man eats about 360 milligrams of cholesterol daily.
The average American woman eats about 240 milligrams of cholesterol daily.
What counts is your daily average over time, not your exact total each day. If you eat scrambled eggs for breakfast on Saturday but eat lean meats, poultry, and fish, along with liberal servings of fruits, vegetables, and grains the rest of the week, your daily average is likely to be below 300 milligrams.
How Do Dietary Carbohydrates Affect Blood Cholesterol?
Carbohydrates come in two varieties - simple and complex.
Simple carbohydrates include:
Refined sugars such as table sugar, brown sugar, and corn syrup
Naturally occurring sweeteners such as honey and sugars present in fruits and vegetables
Complex carbohydrates include:
Starches, found in grain products and starchy vegetables such as potatoes and corn
Dietary fiber, found in whole grain products, fruits, and vegetables
Foods rich in complex carbohydrates include fruits, vegetables, breads, pasta, rice, cereals, dried beans and peas, nuts, and seeds.
Experts recommend that we get 55% to 60% of our calories from carbohydrates - mostly complex carbohydrates. The average American gets 40% to 50% of calories from carbohydrates and about 20% of calories from sugars.
How Can Eating Foods Rich In Starches And Dietary Fiber Help Lower Blood Cholesterol?
Eating more of the foods rich in starches and dietary fiber - fruits, vegetables, whole grains, beans, nuts, and seeds - can help lower your cholesterol level in several ways:
Carbohydrate-rich foods like fruits, vegetables, and whole grains are naturally low in calories. When you eat more of these foods, you will eat less of the foods higher in fat and cholesterol.
Fruits, vegetables, whole grains, beans, and nuts and seeds are good sources of dietary fiber. Dietary fiber, especially a certain type of fiber called soluble fiber, can help lower cholesterol levels by sweeping cholesterol out of the body before it gets to the bloodstream. Especially high in soluble fiber are foods such as oat bran, beans, peas, rice bran, citrus fruits, and psyllium seed (the main ingredient in Metamucil, a fiber supplement available at pharmacies and grocery stores).
Carbohydrate-rich fruits and vegetables also contain vitamin E, vitamin C, beta-carotene and other substances that function as antioxidants. Antioxidants help prevent cholesterol from being moved out of the blood and into the lining of the blood vessels.