Heart disease is America's top health threat. The causes of heart disease are myriad, but the most prevalent include excessive body weight, high-fat diets, sedentary lifestyles, stress, smoking, excessive alcohol use and drug use. Heredity also plays a crucial part in causing heart disease. If you have a family history of heart disease, avoiding other risk factors becomes all the more important.
One way doctors predict who is at risk of heart disease is by measuring their cholesterol levels. Cholesterol occurs naturally in the body and is increased by the foods we eat. Cholesterol in itself is good. It is excessive amounts of cholesterol that contributes to heart disease.
Cholesterol is a waxy substance that our bodies use to make cell membranes. Without membranes, our cells could not exist. Without cells, human beings could not exist. We also could not exist without fat, though we all know too much fat is bad for you. The case with cholesterol is similar.
Cholesterol consists of three types. These three types have different roles in transporting cholesterol and fats around and out of our bodies. When doctors evaluate a person's cholesterol levels, they look at all three types.
The Three Types of Cholesterol
Low Density Lipoprotein (LDL) - This cholesterol is a blob of cholesterol surrounded by lipoprotein, which is the transporter of cholesterol. Though LDL is necessary, too much is bad for heart health, which is why LDL has a common name. Many people call it "bad cholesterol". If too much LDL flows through a person's bloodstream, it becomes a component of plaque. Plaque builds in the arteries and when too much accumulates, blood flow to the heart becomes restricted, which can lead to a heart attack or stroke. Imagine the plaque you scrub off your teeth collecting in the arteries leading to your heart. Having high LDL is like never brushing your teeth, only your life, rather than teeth, is at stake. When you neglect dental hygiene, plaque builds, becomes tartar and causes cavities. When LDL is high, plaque builds, becomes a blockage that starves the heart and causes cardiovascular disease.
Many factors contribute to high LDL. These include heredity, high-fat diets, and low physical activity. Eating a low-fat, high-fiber diet and regular cardiovascular exercise helps keep LDL down. If your LDL is high, your doctor may recommend a low-fat diet and more exercise. In many cases, doctors also prescribe medications to reduce LDL.
High Density Lipoproteins (HDL) - Lots of HDL is great for heart health, so HDL is known as the "good cholesterol." HDL's function in the body is the opposite of LDL. Rather than conveying cholesterol around the body, HDL transports it out. HDL collects cholesterol from other parts of the body and transports it to the liver. The liver then flushes the cholesterol out of the body.
HDL levels vary based on many factors, including heredity and lifestyle. To boost your HDL, consume foods that contain healthy fats, such as olive oil, fish, and walnuts. Avoid bad fats, which include saturated fats and trans fats. These boost LDL and do nothing to help HDL. 30 minutes of aerobic activity per day also helps boost HDL. Moderate alcohol use (1 drink per day max) can also help; however, excessive alcohol use increases the chances of cardiovascular disease.
Though a large amount of cholesterol comes from diet, most is still produced by the liver. For this reason, some people naturally have higher HDL levels and also lower LDL levels, so even if you are healthy and eat well, it is important to have your cholesterol tested to determine if your levels run high or low.
Very Low Density Lipoproteins (vLDL)
These are so low density they don't show up on a regular blood test. Their function is the transportation of triglycerides throughout the body. Triglycerides are a fat that occurs in the bloodstream. As with regular LDL, a high amount of vLDL is bad for the heart. Since vLDL cannot be measured on a blood test, tests instead measure the triglycerides in a person's system. Too many triglycerides means that changes in diet and exercise are needed and possibly medication.
Triglycerides are necessary because the body derives energy from them. When excessive triglycerides sit in a person's system, like LDL, they contribute to plaque and heart disease.
Causes of high triglycerides include obesity, diabetes, underactive thyroid, kidney disease, overeating, excessive alcohol use, and smoking. Certain types of medications can also cause high triglycerides. It can also be hereditary.
High triglycerides can be managed through losing weight, reducing fats and sugars in the diet, increased exercise, limiting alcohol consumption, and quitting smoking.
Cholesterol FAQ
Q: What are healthy cholesterol levels?
A: LDL under 100 is considered optimal; 100-129 is higher than desired; 130-159 is borderline high; 160-189 is high; 190 and above is very high.
A good HDL result is high. HDL above 60 decreases your chances of heart disease. HDL below 40 is undesirable, as it means there is not enough HDL to flush unneeded cholesterol out of your system. Low results should be met with efforts to increase HDL.
A triglyceride score under 150 is normal; 150-159 is borderline high; 200-499 is high; 500 plus is very high.
Q: What is total cholesterol?
A: Total cholesterol is an averaging of LDL, HDL, and triglyceride levels. Though the individual numbers are important in themselves and necessary to compute total cholesterol, doctors use the total cholesterol number to determine a person's propensity for heart disease.
Q: Is high cholesterol alone an indicator of heart disease?
A: Doctors use several factors when determining a person's propensity for heart disease, including age, weight, blood pressure, smoking history, alcohol use, medical conditions, and cholesterol. High cholesterol must be looked at in terms of these other factors to determine risk of heart disease. If your cholesterol is high, it is best to discuss the number with your doctor, who can recommend ways to improve it.
Q: How often should cholesterol be tested?
A: Everyone over 20 should have their cholesterol checked every five years. Doctors will recommend more frequent tests for people with high cholesterol, heart disease, and certain other medical conditions.
Q: Are cholesterol tests accurate?
A: The tests are highly accurate, however, a person's score can be affected by conditions. Patients are instructed to fast prior to the test. Failure to follow the dietary restrictions before the test could affect results.
