Low-Cholesterol Diet

A low-cholesterol diet is a diet designed to reduce the amount of cholesterol circulating in the blood.

No single person originated the low-cholesterol diet. However, the American Heart Association has been a major developer of this diet. The National Cholesterol Education Program organized by the National Heart, Lung, and Blood Institute monitors research and new developments in cholesterol control, including new approaches to low-cholesterol dieting.

The low-cholesterol diet is designed to lower an individual's cholesterol level. Cholesterol is a waxy substance made by the liver and also acquired through diet. Cholesterol does not dissolve in blood. Instead, it moves through the circulatory system in combination with carrier substances called lipoproteins. There are two types of carrier-cholesterol combinations, low-density lipoprotein (LDL) or “bad” cholesterol and high-density lipoprotein or “good” cholesterol.

LDL picks up cholesterol in the liver and carries it through the circulatory system. Most of the cholesterol in the body is LDL cholesterol. When too much LDL cholesterol is present, it begins to drop out of the blood and stick to the walls of the arteries. The arteries are blood vessels carrying blood away from the heart to other organs in the body. The coronary arteries are special arteries that supply blood to the heart. The sticky material on the artery walls is called cholesterol plaque. (It is different from dental plaque that accumulates on teeth.) Plaque can reduce the amount of blood flowing through the arteries and encourage blood clots to form. A heart attack occurs if the coronary arteries are blocked. A stroke occurs if arteries carrying blood to the brain are blocked.

Cholesterol levels

SOURCE: National Heart, Lung, and Blood Institute. “ATP III Guidelines At-A-Glance Quick Desk Reference (NIH Publication No. 01-3305).” National Institutes of Health, U.S. Department of Health and Human Services. https://catalog.nhlbi.nih.gov/sites/default/files/publicationfiles/01-3305.pdf (accessed April 10, 2018).

Researchers believe that HDL works opposite LDL. HDL picks up cholesterol off the walls of the arteries and takes it back to the liver where it can be broken down and removed. This helps to keep the blood vessels open. Cholesterol can be measured by a simple blood test. To reduce the risk of cardiovascular disease, adults should keep their LDL cholesterol below 160 mg/dL and their HDL cholesterol above 40 mg/dL (on average).

Cholesterol is a necessary and important part of cell membranes. It also is converted into some types of steroid (sex)hormones. Cholesterol comes from two sources. The liver makes all the cholesterol the body needs from other nutrients. However, other animals also make cholesterol. When humans eat animal products, they take in more cholesterol. Cholesterol is found only in foods from animals, never in plant foods. The foods highest in cholesterol are organ meats such as liver, egg yolk (but not egg whites), whole-fat dairy products (butter, ice cream, whole milk), and marbled red meat. To reduce the risk of cardiovascular disease, adults should keep their consumption of cholesterol below 300 mg daily.

There are three types of fats in food. Saturated fats are animal fats such as butter, the fats in milk and cream, bacon fat, the fat under the skin of chickens, lard, or the fat on a piece of prime rib of beef. These fats are usually solid at room temperature, and they are considered “bad” fats because they raise LDL cholesterol.

Unsaturated fats can be monounsaturated or polyunsaturated. These fats are considered healthy fats and may help lower cholesterol levels. Olive oil, canola oil, and peanut oil are high in monounsaturated fats. Corn oil, soybean oil, safflower oil, and sunflower oil are high in polyunsaturated fats. Fish oils that are high in omega-3 fatty acids are polyunsaturated and may be beneficial in preventing heart disease.

People who need to reduce their cholesterol levels can get help by reading food labels. Food labels are required to list in the nutrition information panel nutrition facts that include calories, calories from fat, total fat, saturated fat, trans fat, cholesterol, sodium, total carbohydrates, dietary fiber, sugars, protein, vitamin A, vitamin C, calcium, and iron. In addition, the following words have specific legal meanings on food labels:

When cooking, people can reduce cholesterol in the diet in the following ways:

To reduce cholesterol in meals when eating out:

In addition to reducing fats, increasing soluble dietary fiber that is found in whole grains also helps lower cholesterol. Soluble fiber is found dissolved in water inside plant cells. In the body, it lowers LDL cholesterol. Good sources of soluble fiber include:

Low-cholesterol diets are healthy diets that are most effective if they become lifetime habits. Low-cholesterol diets work by reducing the amount of saturated (animal) fat to drive down LDL cholesterol and using more monounsaturated fats (olive oil, canola oil) and soluble fiber to drive up HDL cholesterol. By controlling fats in the diet, individuals may also lose weight.

Low-cholesterol diets have the following benefits:

Anyone over age two can safely follow a low-cholesterol diet. Children under age two need certain fats for the normal development of the nervous system and should be given whole-milk and whole-milk products.

There are no known risks to following a low-cholesterol diet.

The relationship between cholesterol, saturated fat intake, and heart health has been documented in many studies. However, in a study of 49,000 women between the ages of 50 and 79 that was published in February 2007 in the Journal of the American Medical Association, women were divided randomly into a group that ate a low-fat diet and another group that had no restrictions and ate the average American diet. Researchers found no significant difference in the rates of heart attack or stroke between the two groups. They concluded that there was no justification in recommending a low-fat diet to the public as protection against heart disease. This study is particularly important because it was large, well-designed, and independent (it was funded by the federal government), and it followed the women for eight years. The American Heart Association has questioned these findings and continues to recommend a diet low in fat (especially animal fats) and low in cholesterol for the prevention of heart disease.

Critics of this study claim that the low-fat group did not reduce their fat significantly enough to make a difference in health and that the study did not cover enough time. Others said that eating unsaturated fat (a Mediterranean diet) was heart healthy and that this study did not distinguish between saturated and unsaturated fat intake. Supporters of the study have said that it shows that how much people eat and how much they exercise (their calorie balance) are more important than what they eat.

In a May 2009 article about risk factors for heart disease, the Journal of the American Medical Association recommended that individuals “Check food labels and avoid saturated (usually from animals) fats and foods made with trans fats or hydrogenated fats.”

See also Coronary heart disease; Dean Ornish's Eat More, Weigh Less; Dietary cholesterol; Flaxseed; Gallstones; Heart-healthy diets; Low-fat diet; Omega-3 and omega-6 fatty acids; Trans fats.

Tish Davidson, AM
Revised by Laura Jean Cataldo, RN, EdD