HDL & LDL Cholesterol

Here’s what you need to know about HDLs, LDLs, and all those confusing numbers.

Back To Basics

Despite the negative connotation attached to it, cholesterol is essential to your life. It’s the primary element of the membrane that surrounds every cell in your body—without cholesterol, your body won’t synthesize vitamin D, bile acids, or steroid hormones. Cholesterol is found in all animal tissues—cheese, butter, rib-eye steaks, chicken tenders, you name it. It isn’t found, however, in any plant tissues, which is why vegetable oil is labeled “cholesterol-free.”

To reach every cell in your body, cholesterol travels in the bloodstream. It’s a waxy, fat-like substance formed in the liver that won’t dissolve in blood. Instead, it’s carried along by lipoproteins, tidy combinations of fat and protein that can take on cargo and sail through the bloodstream.

Low-density lipoproteins (LDLs) carry cholesterol out from the liver to all the cells. The LDLs dock and offload the cholesterol cargo at cell receptor sites. But the cells are only going to take so much—they have their limits, after all.

Excess cholesterol continues to travel around in the blood. The extra LDL packaging and the cholesterol can snag in the artery walls and contribute to the buildup of plaque. Excessively high levels of LDLs can contribute to atherosclerosis, or hardening of the arteries. The greatest contributor to high cholesterol levels is the cholesterol made in the liver from the fat we eat—particularly saturated fat.

High-density lipoproteins (HDLs) gather up and return unused cholesterol to the liver, where it’s removed from the blood and excreted from the body. HDLs work against hardening of the arteries, which is why they are often called “good” cholesterol.

Healthy eating habits (those involving with less dietary fat and cholesterol) and regular exercise help increase the amount of HDLs in your blood and reduce the amount of LDLs. Smoking, on the other hand, reduces desirable HDLs. Your total cholesterol level is measured from a blood sample as milligrams of total cholesterol per deciliter of blood (mg/dl). A total cholesterol reading of 200 mg/dl or lower is good; a reading of 240 mg/dl or higher needs attention because it is approaching an unhealthy level.

The Benefits Of A Healthy Diet And Regular Exercise

High blood cholesterol can contribute to coronary heart disease, but by itself doesn’t cause it. While high blood cholesterol is a risk factor for coronary heart disease, it is merely one of several risk factors, and they should all be considered together, case by case.

If you were a man over 60 with a family history of heart disease, if you didn’t exercise, if you smoked and were overweight, and if your cholesterol reading was on the high side, you might be looking at a heart attack in the next five years. Treatment shouldn’t just focus on bringing down high cholesterol; it should be aimed at reducing all the risk factors you can control—smoking, diet, exercise, etc.

Isn’t There A Pill Or Something?

While there are, in fact, new medications to lower cholesterol, they are used as a last resort. If there’s a high probability of heart attack in the next five years due to your risk factors—and your cholesterol is high—then medication is a route worth exploring. But that’s something to work out with your doctor, and only then after you’ve tried bringing your cholesterol down by other means.

How To Bring Down Your Cholesterol

You can often lower your cholesterol by making a few lifestyle adjustments. Here’s how:

  • If you smoke, stop right now. If you don’t smoke, don’t start. Smoking reduces HDLs, the “good” cholesterol that you want to be as high as possible.
  • Exercise regularly. Exercise reduces LDLs, the “bad” cholesterol, and increases HDLs, the good cholesterol.
  • Drink alcohol in moderation.
  • Reduce the fat intake in your diet.
  • Reduce the stress in your life.
  • If you are overweight, try to lose those extra pounds.

Everything you do to reduce cholesterol helps you lose weight and lower blood pressure. Everything you do to lower blood cholesterol is good for your heart, helps prevent colon cancer, and benefits you as you grow older.

Men between 40 and 65 should have their cholesterol checked, and then consider a test every five years if all cholesterol levels are desirable and they are not at high risk for heart disease. Women between 50 and 65 should consider having their cholesterol checked, and then tested again in five-year intervals if all cholesterol levels are desirable and they are not at high risk for heart disease. Cholesterol screening is most important for people at high risk for heart disease.

Have More Questions?

If you have questions after this examination is completed, ask your personal physician.

What Do The Cholesterol Numbers Mean?

The most commonly used cholesterol values are listed below. The rule of thumb: You want HDL to be high, while LDL should be low.

Desirable—All of the following:

Total cholesterol below 200.
HDL cholesterol above 35. LDL cholesterol below 130.
Total-to-HDL ratio below 3.5 to 1.
LDL-to-HDL ratio lower than 3 to 1.

Borderline High-Risk—One or more of the following:
Total cholesterol level of 200 to 239.
LDL cholesterol level of 130 to159.
Total-to-HDL ratio of 3.5 to 4.5 to 1.

High-Risk—One or more of the following:
Total cholesterol level of 240 or higher.
HDL cholesterol below 35.
Total to HDL ratio of 4.5 to 1 or higher.
LDL or HDL ratio of 3 to 1 or higher.

The Low Cholesterol Diet

Fats should make up no more than 30 percent of the calories you eat in a day, according to the American Heart Association. To make a more significant reduction in the amount of fat in your diet, aim for 20-25 percent.

Keep saturated fats to a minimum. They are found in animal products (meat, fish, poultry, eggs, butter, cheese) and in tropical oils (used in snack foods and baked goods).

Monounsaturated fats (olive oil, canola oil) can lower LDLs.