Cholesterol is a substance that looks like fat and is found in the cells of people and other animals. It is an important part of the structure of cell membranes, certain hormones, and the process of making vitamin D. All of the cholesterol we need for these important things comes from our livers. Antherosclerosis, or hardening of the arteries, can be caused by too much cholesterol.
Cholesterol is in all foods that come from animals, like meat, eggs, fish, chicken, and dairy products. Some animal foods have a lot of cholesterol in them, while others only have a small amount. There is no cholesterol in foods that come from plants. Too much cholesterol in your diet can raise your blood cholesterol, which can make you more likely to get coronary heart disease.
Cholesterol is usually called either "good cholesterol" or "bad cholesterol." First, we need to explain what "lipoproteins" means so that we can better understand the two and how they are different. These are packages of proteins, cholesterol, and triglycerides that the liver puts together and then sends through the blood. Low density lipoprotein cholesterol, or LDL cholesterol, is what we mean when we talk about cholesterol. High density lipoprotein cholesterol is what we mean when we talk about HDL cholesterol.
LDL cholesterol, which is often called "bad cholesterol," carried cholesterol through the bloodstream. It dropped the cholesterol off where it was needed to build cells and left any extra cholesterol on the walls of the arteries as plaque.
HDL cholesterol, which is often called "good cholesterol," picks up cholesterol that has built up in the arteries and takes it back to the liver to be reprocessed or passed out of the body.
Now that you know what each kind of cholesterol does, it's easy to see why there's a difference between good and bad cholesterol.
Most saturated fats come from animal products, like lard, the fat in meat and chicken skin, butter, ice cream, milk fat, cheese, etc. High-saturated oils are also found in coconut oil and palm oil. Most of the time, these fats are solid at room temperature. You've probably heard that you should limit your intake of saturated fats, but do you know why? Because these fats tend to raise the amount of cholesterol in your blood, which makes you more likely to get coronary heart disease.
Hydrogenated fats are liquid vegetable oils that have been changed through a chemical process into solid saturated fats. These fats also raise the amount of cholesterol in your blood.
Polyunsaturated fats are made from plants and are liquid when they are at room temperature. Some examples of oils are safflower, corn, soy, cottenseed, and sunflower. Polyunsaturated fats tend to lower LDL cholesterol, but too much of them can also lower HDL cholesterol (good cholesterol).
Monounsaturated fats come from plants as well. Olive oil and canola oil are two examples. By eating more monounsaturated fats instead of saturated fats, you can lower your LDL (again, bad cholesterol) without lowering your HDL (good cholesterol). Monounsaturated fats are good for your heart because of this. But remember that too much of any kind of fat can lead to being overweight.
Bottom line: When choosing which fats to eat, remember that good heart health depends on keeping your LDL cholesterol low while keeping your HDL cholesterol steady.
