Cholesterol is a waxy fat that is present in all human beings. It can be found in the bloodstream and in the body’s cells. About 80 percent of the cholesterol in the body is manufactured by the liver. The rest is consumed through cholesterol-rich foods such as meat, eggs and dairy products.
Cholesterol itself is vital for survival. However, it can also contribute to coronary artery disease. The body needs a certain amount of cholesterol to aid in the formation and maintenance of cell membranes to help the body resist changes in temperatures and protect and insulate nerve fibers. Cholesterol is also used in the production of hormones in the body including testosterone, progesterone, estradiol, and cortisone. Also, it produces bile salts, which help in digestion.
Too much cholesterol can lead to cardiovascular disease, which can result in a heart attack. Cholesterol and fat cannot travel through the body in their original form because they do not mix with water, the main component of blood. Cholesterol and fat are grouped with proteins to make lipoproteins, which travel through the blood. There are three types of lipoproteins: low-density lipoproteins (LDL), high-density lipoproteins (HDL), and very low-density lipoproteins (VLDL).
Low-density lipoproteins (LDL) are known as &quot;bad&quot; cholesterol. Having too much LDL can cause some cholesterol to stick to blood vessels forming plaques; these are thick, hard deposits that can cause arteries to clog. This condition is called atherosclerosis, and it can lead to a heart attack or stroke. High-density lipoproteins (HDL) are known as “good” cholesterol because they pick up the LDL cholesterol that sticks to the blood vessel walls and takes it back to the liver where it is eventually eliminated out of the body. VLDLs are made in the liver to carry fat to other parts of the body. The leftover pieces change into LDL. Triglycerides are also important. They are a form of fat found in the blood. Triglycerides come from fats in foods or are made in the body from energy sources like carbohydrates. Calories eaten during a meal that are not used immediately by tissues are converted to triglycerides and transported to fat cells to be stored. Having elevated triglycerides can also be a complication due to diabetes.
One gets cholesterol through two ways. The body makes some in the liver to keep the cells working; the rest comes from foods. Foods high in cholesterol include fatty meats, poultry, fish, eggs, butter, cheese, and whole milk. Foods high in saturated fat can allow the body to overproduce cholesterol.
What happens to the cholesterol in the diet?
After the high-fat foods are ingested, the fat passes through the stomach and small intestine and is sent to the liver. The liver changes fat and cholesterol into VLDLs that travel through the blood vessels unloading the fat; the remainder becomes LDLs. LDL cholesterol travels through the blood vessels and some sticks to the vessel walls. HDL picks up the stuck cholesterol and brings it back to the liver where they are made into new VLDLs or broken down and eliminated out of the body. If one eats too much fat, the liver will make extra VLDLs, which eventually become LDLs. Therefore, more of the cholesterol is left in the blood vessels making them narrower. If there is not enough HDL to pick up the LDLs, the blood vessels can become blocked.
You can lower your cholesterol by exercising more and eating more fruits and vegetables. You also may need to take medicine to lower your cholesterol.
Adults age 20 or over should have a fasting cholesterol profile once every 5 years and at age 45 or over testing should be every few years. A fasting profile means that no food has been eaten in the past 9 to 12 hours. A blood sample is taken and analyzed by a laboratory. If a patient is nonfasting, only total cholesterol and HDL can be evaluated. If values are abnormal or if certain medical problems such as type 2 diabetes are present, more frequent testing is recommended. There are separate values and considerations for adolescents.
Public or private testing is available. A private test can be done with your healthcare provider. Public screenings may be held in schools, churches, community centers or neighborhood clinics. They should be provided at reasonable cost and at sites that ensure quality control procedures and privacy. Screenings should include reliable verbal and printed information about cholesterol levels from knowledgeable staff.
The other option is home cholesterol test. There are many home cholesterol test kits available. Some measure only the total level of cholesterol while other can measure also high-density lipoprotein (HDL) and low-density lipoprotein (LDL) values. The kits offer quick and accurate results in the privacy of your own home.
Home cholesterol test was approved by the FDA in 1993. To use it, you prick your finger with a small lancet, put a drop of blood on a piece of paper with chemicals on it, and wait for the results. Usually it takes 10 minutes or so. The results of home cholesterol tests are about 95% accurate. This is close to the accuracy of a clinical test. Typical home cholesterol test costs not more than $20 and saves you trips to the doctor’s office or medical laboratory.