Cholesterol and Fats

 

by J. Anderson, L. Young, and J. Roach1 (revised 12/08)

Quick Facts...

Cholesterol

What is cholesterol? Cholesterol is a waxy, fat-like substance found in all animals including people. It is an essential part of cells in the body and is used to make certain hormones and digest fats. there are two different types of cholesterol. Blood, or serum, cholesterol circulates in the blood. Dietary cholesterol comes from the food we eat.

Is all blood cholesterol the same? the chemical substance is the same. However, it is transported in the blood by different carriers. the relative amounts of cholesterol transported by each carrier can affect the risk of heart disease. the two major blood cholesterol carriers are LDL and HDL (see Table 1).

Where do we get cholesterol? Our bodies can make all of our cholesterol, but most people also get it from foods. Different foods vary in the amount of cholesterol they contain. Only animal products have cholesterol; plants do not. See Table 5.

Table 1: Characteristics of HDL and LDL.
LDL HDL
Full Name: Low Density Lipoprotein. High Density Lipoprotein.
What it does: Takes cholesterol from the liver to the rest of the body. Primarily takes cholesterol from body tissue back to liver.
Effect on risk of heart disease: Excess amounts increase risk. High amounts reduce risk.
Nickname: "Bad" cholesterol. "Good" cholesterol.

Is it harmful? Cholesterol is necessary for a healthy body. By itself, it is not harmful. However, a high blood level of total cholesterol is a major risk factor for heart disease, along with high levels of LDL cholesterol. the higher the level, the greater the risk. In contrast, high levels of HDL cholesterol are protective.

the National Cholesterol Education Program (NCEP) recommends that everyone age 20 and older obtain what is called a “fasting lipoprotein profile” every five years. this is a blood test done after a 9 to 12 hour fast without food, liquids or pills. It reveals information about the total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride levels in the blood. Table 2 shows how the results from a fasting lipoprotein profile are classified.

the results of the test, along with other factors, can help determine your overall risk for heart disease. When determining your total risk, consider other risk factors such as age, gender, family history, smoking, hypertension, diabetes, and obesity.

Table 2: Classifications of a Fasting Lipoprotein Profile.
Total Cholesterol
Desirable < 200 mg/dL
Borderline High 200 – 239 mg/dL
High > 240 mg/dL
LDL Cholesterol
Optimal < 100 mg/dL
Borderline High 100 – 129 mg/dL
Borderline High 130 –159 mg/dL
High 160 – 189 mg/dL
Very High > 190 mg/dL
HDL Cholesterol
Low < 40 mg/dL
High1 > 60 mg/dL
Triglycerides
Normal < 150 mg/dL
Borderline High 150 –199 mg/dL
High 200 – 499 mg/dL
Very High > 500 mg/dL
1An HDL of 60 mg/dL and above is considered protective against heart disease.

Fats

Is eating fat unhealthy? Eating some fat is necessary. It is an important source of essential fatty acids (linolenic and lionoleic acids) and concentrated energy — it has more than twice as many calories per ounce as sugar, starch or protein. Fats help carry fat-soluble vitamins A, D, E and K. Fats can also make food taste better, aid in cooking, and help keep the hunger pangs away.

Yet, eating too much fat may lead to obesity, which is unhealthy. It also may increase the risk of heart disease and some forms of cancer.

Nutrition Facts
This label tells you that this spinach souffle provides 10 g total fat in a half cup serving. this is 15% of the Daily Value for total fat, based on a 2,000-calorie diet: 10 grams fat / 65 g total fat in a 2,000-calorie diet = 15%. (See fact sheet 9.365, Understanding the Food Label). Evaluate your diet as a whole. the percent of calories from fat for the entire diet is more important than the percentage of fat from an individual food.

Are all fats the same? there is not a single type of fat. Rather, the word “fat” is often used to refer to all of the fatty substances found both in food and in the body.

Types of Fat (see Table 3)

Essential Fatty Acids: Types of fat that cannot be made in the body. We must eat foods rich in these as they are the building block for other important fatty acids (e.g., DHA/EPA).

Lipid: Scientific term referring to fat, cholesterol and other fat-like substances. A common quality among lipids is that they do not dissolve in water.

Lipoprotein: A protein-coated transporter that carries fat and/or cholesterol in the bloodstream.

Triglycerides: Scientific name for the main form of fat found in the diet and in the body. Most of the fat in the body is stored as triglycerides.

Saturated Fats: Usually solid at room temperature, saturated fats have all of the hydrogen atoms they can hold (saturated with hydrogen). Saturated fats primarily come from animal products, but are also found in tropical plant oils, such as coconut and palm.

Monounsaturated Fats: Liquid at room temperature, monounsaturated fats are missing one pair of hydrogen atoms. Monounsaturated fats primarily come form plants and include olive oil, canola oil and peanut oil.

Polyunsaturated Fats: Liquid at room temperature, polyunsaturated fats are missing two or more pairs of hydrogen atoms. Many common vegetable oils, such as corn, soybean, safflower and sunflower oil, are high in polyunsaturated fats.

Hydrogenated Fats: Polyunsaturated fats and monounsaturated fats are sometimes processed to make them solid at room temperature and to protect against rancidity. Hydrogen atoms are added through a process called hydrogenation.

Trans Fatty Acids: A type of fat formed during the process of hydrogenation. Trans fatty acids have been shown to increase LDL cholesterol and lower HDL cholesterol, which may increase the risk for heart disease.

Omega-3 Fatty Acids: A type of fatty acid that is highly polyunsaturated. Omega-3 fatty acids are mainly found in higher-fat, cold-water fish, such as salmon, mackerel and herring as well as omega-3 fortified eggs. Diets high in omega-3 fatty acids may help lower levels of LDL cholesterol and triglycerides.

Table 3: Polyunsaturated, monounsaturated and saturated fats.
Polyunsaturated (fats, oils) Monounsaturated (fats, oils) Saturated (fats)
Amounts of hydrogen: Missing many hydrogen atoms. Missing some hydrogen atoms. Filled up with hydrogen.
How they affect our health: Can lower blood cholesterol, may lower HDL. Lowers blood cholesterol but not HDL. Can raise blood cholesterol.
At room temperature: Polyunsaturated and monounsaturated fats are liquid (so we call them oils). Saturated fats are usually solid or firm.
Where they come from: Mostly from plants: safflower oil, corn oil, soybean oil, cottonseed oil, sesame oil Mostly from plants: olive oil, peanut oil, canola oil Mostly from animals: fat in meat, butter, lard, cheese, whole milk, cream. Some from plants: coconut oil, palm oil, cocoa butter (in chocolate), hydrogenated vegetable oil

Fats and Cholesterol

How are fats related to blood cholesterol? Scientific evidence indicates that the amount and type of dietary fat can affect blood cholesterol. Eating less fat, especially saturated fats, has been found to lower blood cholesterol levels. Replacing some saturated fats with polyunsaturated and monounsaturated fats (especially olive and canola oil) also can help lower blood cholesterol. Dietary cholesterol can raise blood cholesterol but generally is not as important as saturated fat and total fat in the diet. Remember, high total blood cholesterol levels and LDL cholesterol levels increase risk of heart disease while lower levels reduce risk. Higher levels of HDL cholesterol help lower the risk for heart disease.

How much fat and cholesterol is too much? Frequently, recommendations for fat are given in percentage of calories from fat or fat calories. Currently, the average American gets about 33 percent of total calories from fat. Most medical experts think this is too much. the U.S. Dietary Guidelines advise a general reduction in fat (especially saturated fat) and cholesterol. Dietary recommendations by the American Heart Association and the National Cholesterol Education Program for fat and cholesterol intakes for both the general public and for people with high LDL cholesterol, heart disease and/or diabetes are presented in Table 4.

Diet therapy may not be enough for some people with high risk. Most people, however, continue diet therapy at least six months before deciding whether to add drug treatment.

Children can eat a diet consistent with adult guidelines to maintain appropriate growth while lowering risk for future cardiovasular disease. Adoption of a healthy diet and lifestyle in youth is recommended because it tracks into adulthood.

Table 4: Recommendations for Calories, Fat and Cholesterol Intakes*
Nutrient People without Heart Disease or High LDL Cholesterol People with Heart Disease, Diabetes, or High LDL Cholesterol
Total Calories Balance calorie intake and physical activity to achieve or maintain a healthy body weight.
Total Fat Less than 30% of total calories 25 – 35% of total calories1
Saturated Fat Less than 10% of total calories Less than 7% of total calories
Polyunsaturated Fat
Up to 10% of total calories
Monounsaturated Fat
Up to 20% of total calories
Cholesterol Less than 300 mg/day Less than 200 mg/day
*By the American Heart Association and the National Cholesterol Education Program
1A higher fat intake is allowed, provided most of it is unsaturated fat, and may be needed to prevent low HDL levels from worsening

In what foods are fats and cholesterol found? In some foods, fats are obvious, such as in noticeably greasy, fried or oily foods. In other foods, they are more invisible. Cholesterol comes from animal products but has no tell-tale signs. It is not found in food products made from plants. A food can be high in fat and cholesterol (fried egg), high in fat but low in cholesterol (peanut butter), low in fat and high in cholesterol (shrimp) or low in both (fruit). Table 5 shows the fat and cholesterol contents of several foods.

What about fish and fish oil supplements? Diets high in fish, especially cold-water fish like salmon, herring, mackerel, and whitefish, have been linked to reduced risk of heart disease. People who eat large amounts of fish tend to have lower blood cholesterol and triglyceride levels. the high amounts of omega-3 fatty acids found in fish are believed to be the reason. the current recommendation is to consume a variety of fish (preferably oily) at least two times per week. the use of fish oil supplements could be considered with consultation with your doctor, especially in individuals with cardiovascular disease and elevated triglycerides.

Reducing Fat and Cholesterol

Read labels and shop carefully. the Nutrition Facts panel on the food label provides the necessary information to help consumers meet the American Heart Association’s and the USDA/Health and Human Services’ Dietary Guidelines. the Nutrition Facts panel lists the Daily Reference Values (DRV) for specific nutrients, including fat, saturated fat and cholesterol. DRVs are set by the Food and Drug Administration and are intended to help consumers evaluate their food choices to determine how their intake of certain nutrients compares to desirable intakes.the DRV for fat is 65 g, for saturated fat 20 g, and for cholesterol 300 mg.

Specific health claims can be made for food products that meet certain requirements. For example, “While many factors affect heart disease, diets low in saturated fat and cholesterol may reduce the risk of this disease.” In order to make a health claim about heart disease and fats, the food must be low in fat, saturated fat and cholesterol. Terms “lean” and “extra lean” can be used to describe the fat content of meat, poultry, seafood and game meats if certain standards are met.

Products that have “percent fat free” claims must accurately reflect the amount of fat present in 100 grams of the food. “Percent fat free” products must meet the low fat or fat free product definitions. For example, if a product contains 2.5 grams of fat per 50 grams, the claim must be “95 percent fat free.”

Learn the heart-healthy facts. It is true that fat and cholesterol often are found
in meats, but meats can provide many important nutrients. Many people think chicken and fish are healthier than red meat. However, with careful selection and preparation, red meats can be low in fat and included in a healthy-heart diet.

Remember, chicken and fish, which often are low-fat choices, can be prepared
so they are higher in fat than lean beef or pork. Dark meat poultry has more fat than white meat. Keeping the skin on chicken or frying it adds more fat. What you buy at the store and how you cook the food makes the difference.

To reduce meat fats: Examples of lean meat choices:

Beef -- round steak, rump roast, top ground steak and roast, tip steak and roast, lean cubed steak, top loin steak, tenderloin steak, flank, sirloin, ground beef, lean or extra lean.

Pork -- leg roast (fresh ham), leg steak, lean pork cutlets, center rib chop and roast, butterfly chop, sirloin roast, tenderloin, tenderloin roast, ground pork, lean or extra lean, lean shoulder cubes, lamb-leg, loin chops.

Change recipes to reduce fats. Many favorite recipes can still be used in a reduced-fat diet.

Watch portion sizes. Moderation is the key. For example, a lean 3-ounce meat portion provides you with the nutrients you need. A piece of meat the size of a deck of cards is about a 3-ounce portion. Don't eliminate -- just cut down. Eat high-fat food less often and in small portions.

Increase fiber intake. Research has shown eating foods rich in soluble fiber may decrease LDL cholesterol levels. Foods high in soluble fiber include cereal grains, beans, peas, legumes and many fruits and vegetables. For more information see fact sheet no. 9.333 Dietary Fiber.

There are several things you can do to reduce the amount of fat and cholesterol you eat.

Table 5: Spotting hard to see fats and cholesterol in foods.
Category, food Serving size Grams fat per serving Cholesterol (mg/dl)
Dairy
ice cream 1 cup 14 59
egg, cooked 1 6 213
cheddar cheese 1 oz. 9 30
Meat
regular ground beef cooked (70% lean) 1 patty 12 60
hot dogs 1 16 30
chicken leg w/skin 1 20 139
Nuts and seeds
peanut butter 1 Tbsp. 8 0
Baked goods
doughnut, glazed
(3 1/4" diameter)
1 14 4
brownies (2 3/4" x 7/8") 1 square 9 10
Candy
chocolate 1 oz. 9 7
Other
olives, giant size 5 3 0

* Fats do not always come in teaspoons, but all fat must be counted in what you eat each day. For example, the fat in a hot dog cannot be measured with a teaspoon, but it may be a big source of fat, contributing 3 teaspoons per 2 ounces of hot dog.

References: National Heart, Lung and Blood Institute. Executive Summary of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Journal of the American Medical Association, 285(19): 2486-97, 2001.

American Heart Association. Diet and lifestyle recommendations revision 2006: A scientific statement from the American Heart Association nutrition committee. Circulation, 114:82-96, 2006.

U.S. Department of Agriculture. Agricultural Research Service.
Nutrient intakes from food: Mean amounts and percentages of calories from protein, carbohydrate, fat, and alcohol, One day, 2003 - 2004. 2007. Or www.ars.usda.gov/ba/bhnrc/fsrg.

1 J. Anderson, Colorado State University Extension food and nutrition specialist and professor, food science and human nutrition; L. Young, M.S., former graduate student; and J. Roach, M.S., graduate student. 5/96. Revised 12/08.

Colorado State University, U.S. Department of Agriculture, and Colorado counties cooperating. CSU Extension programs are available to all without discrimination. No endorsement of products mentioned is intended nor is criticism implied of products not mentioned.