Cholesterol and Saturated Fats Can Increase Heart Attack Risk

by Laverne Davis, M.T., ASCP

Cholesterol is a soft, waxy, fat-like substance found only in animals. It travels in the bloodstream to all body cells, helps form cell membranes, is a "building block" of certain hormones, and is a part of bile that digest fats. It is made primarily by the liver. Most of the dietary cholesterol is contained in egg yolks and animal fat. Your body needs some cholesterol to function normally, but too much cholesterol can increase the risk of heart disease. Actually, you could eat no cholesterol at all, as your liver is capable of making enough to supply your body's needs.

Fats are essential nutrients, yet only very small amounts are needed to satisfy your body requirements. Fats also travel in the bloodstream. There are two major kinds of body fat: saturated fat and unsaturated fat. Saturated fats are not only found in animals but also in some vegetable products. Some animal sources of saturated fats are: meat, fish, poultry and dairy products. Some vegetable oils such as palm oil and coconut oil, as well as cocoa, are mainly saturated. Diets rich in saturated fats tend to increase blood cholesterol. The higher your blood cholesterol, the greater your chance of heart attack.

Unsaturated fats are found mainly in vegetable products. There are two types of unsaturated fats. Monounsaturated fat is found mostly in foods from plants such as peanuts and avocados, and in canola and olive oils. Polyunsaturated fats are found in safflower, sunflower, corn, and soybean oils. Both of these unsaturated fats help reduce blood cholesterol levels and are considered far healthier than saturated fat.

Sometimes an unsaturated fat is changed chemically in order to prolong shelf life of a product. This process, known as "hydrogenation," increases the saturated fat content and is found in most snack foods, cakes, cookies, and many other food preparations. On the labels of foods that have undergone this process, you will read: "Contains [or may contain] hydrogenated vegetable oil(s)." Not only are you getting a vegetable oil that is more saturated than usual but it is a more synthetic, unnatural food.

It is easier to understand how cholesterol and saturated fats can be harmful to your health if you become more familiar with a few terms used to describe fatty substances. We know that cholesterol is a fatty substance found in the blood and body tissues. Triglycerides are considered a fatty substance and are also found in the blood and body tissues. Both cholesterol and triglycerides are known as "lipids." Triglycerides are made up of smaller units called fatty acids. Three chief fatty acids are saturated fat, monounsaturated fat, and polyunsaturated fat.

Because cholesterol does not dissolve in the bloodstream, both cholesterol and triglycerides are transported by carriers. These transport carriers are protein-coated packages called lipoproteins. Total cholesterol consists of a combination of lipoproteins: very low-density lipoproteins (VLDL), which eventually become low-density lipoprotein (LDL), and high-density lipoprotein (HDL). The lipoprotein that carries the greatest amount of cholesterol in the bloodstream and is responsible for depositing cholesterol in the arterial walls is LDL-Chol (known as the "bad cholesterol"). This bad cholesterol tends to stick to the artery walls. The HDL-Chol is now known as the "good cholesterol" because it carries the bad cholesterol (LDL-Chol) away from the artery walls and returns it to the bloodstream.

When cholesterol, fat, and other blood components build up in arterial walls, it causes a "hardening of the arteries" known as atherosclerosis. If this occurs in the arteries that normally supply the heart with oxygen-rich blood and nutrients, these coronary arteries, now narrowed and hardened, can't perform their function. The result can be coronary heart disease (CHD).

Lipids (fats) are valuable components of both our bodies and our foods. Lipoproteins are also important because high levels of LDL means high total cholesterol. But a high level of HDL protects our blood vessels from atherosclerosis. Many Americans eat far more fatty foods and high cholesterol foods than is healthy. Saturated fats and cholesterol have been directly linked with heart disease. There are additional risk factors such as tobacco smoking, obesity, high blood pressure, family history, and diabetes. Most of these risk factors can be modified and for many people heart disease and atherosclerosis can be prevented or delayed.

For more information on how to eat healthier and for an assessment of your individual risk factors, join us at the Waimanalo Health Center Community Health Fair on Saturday, May 25th from 10:00 AM to 4:00 PM. In addition to health education, cholesterol, diabetes and blood pressure checks, there will be entertainment, food, games, and prizes.

Laverne Davis is a Medical Technologist (specialized in clinical laboratory procedures) at Waimanalo Health Center.