Cholesterol – the Good (HDL), the Bad (LDL) and the Ugly (Heart Disease)

Too much cholesterol in the blood is one of the main risk factors for heart disease and stroke—two leading causes of death in the United States. One way to prevent these diseases is to detect high cholesterol and treat it when it is found.

What is cholesterol? 

Cholesterol is a waxy, fat-like substance that your body needs.  However, cholesterol can’t dissolve in the blood.  It has to be transported to and from the cells by carriers called lipoproteins.  Low-density lipoprotein, or LDL, is known as “bad” cholesterol. High-density lipoprotein, or HDL, is known as “good” cholesterol.  These two types of lipids, along with triglycerides and Lp(a) cholesterol, make up your total cholesterol count, which can be determined through a blood test.  When you have too much cholesterol in your blood, it can actually build up on the walls of your arteries and form blockages.  This can lead to heart disease, heart attack, and stroke.


Approximately one-fourth to one-third of blood cholesterol is carried by high-density lipoprotein (HDL).  HDL cholesterol is known as “good” cholesterol, because high levels of HDL seem to protect against heart attack.  Low levels of HDL also increase the risk of heart disease.  Medical experts believe that HDL tends to carry cholesterol away from the arteries and back to the liver, where it’s then passed from the body.  Some experts also believe that HDL removes excess cholesterol from arterial plaque, slowing its buildup.


LDL cholesterol is known as the “bad” cholesterol.  When too much LDL cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain.  Together with other substances, it can form plaque, a thick, hard deposit that can narrow the arteries and make them less flexible.  This condition is known as atherosclerosis.  If a clot forms and blocks a narrowed artery, heart attack or stroke can result.


Triglyceride is a form of fat made in the body.  Elevated triglycerides can be due to obesity, physical inactivity, cigarette smoking, excess alcohol consumption or a diet high in carbohydrates.  People with high triglycerides often have a high total cholesterol level, including a high LDL “bad” level and a low HDL “good” level.  Many people with heart disease and diabetes also have high triglyceride levels.

Lp(a) Cholesterol

Lp(a) is a genetic variation of LDL “bad” cholesterol.  A high level of Lp(a) is a significant risk factor for the premature development of fatty deposits in arteries. Lp(a) isn’t yet fully understood, but it may interact with substances found in artery walls and contribute to the buildup of fatty deposits.


Screening is the key to detecting high cholesterol.  Because high cholesterol has no symptoms, many people have no idea their cholesterol is too high.  Your doctor can do a simple blood test to check your cholesterol levels.  The National Cholesterol Education Program recommends that adults aged 20 years and older have their cholesterol checked a minimum of every 5 years.  You may need to have it checked more frequently if you have other risk factors for heart disease and stroke.


Prevention and Treatment


The easiest way to prevent high cholesterol is by making healthy lifestyle changes.

  • Eat a healthy diet – avoid saturated fats and trans fats, which tend to raise cholesterol levels.  Other types of fats, such as polyunsaturated fats, can actually lower blood cholesterol levels.  Eating fiber can also help lower cholesterol.
  • Exercise regularly – physical activity can help lower cholesterol.  The Surgeon General recommends that adults engage in moderate-intensity exercise for 2 hours and 30 minutes every week.
  • Maintain a healthy weight – being overweight or obese can raise your cholesterol levels.  Losing weight can help lower your cholesterol.
  • Quit smoking – if you smoke, quit as soon as possible.
  • Medications – if you are prescribed medications to lower your cholesterol levels, be sure to follow your doctor’s instructions and stay on them.

According to the Centers for Disease Control (CDC), seventy-one million American adults have high cholesterol, but only one-third of them have the condition under control.  National Cholesterol Education Month is the perfect time to get your cholesterol screened.