Heart Disease and Lowering Cholesterol

Medically Reviewed by Murtaza Cassoobhoy, MD on March 19, 2023
8 min read

Cholesterol helps your body build new cells, insulate nerves, and produce hormones. Normally, the liver makes all the cholesterol the body needs. But cholesterol also enters your body from food, such as animal-based foods like milk, eggs, and meat. Too much cholesterol in your body is a risk factor for heart disease.

When there is too much cholesterol in your blood, it builds up in the walls of your arteries, causing a process called atherosclerosis, a form of heart disease. The arteries become narrowed and blood flow to the heart muscle is slowed down or blocked. The blood carries oxygen to the heart, and if not enough blood and oxygen reach your heart, you may suffer chest pain. If the blood supply to a portion of the heart is completely cut off by a blockage, the result is a heart attack.

There are two forms of cholesterol that many people are familiar with: Low-density lipoprotein (LDL or "bad" cholesterol) and high-density lipoprotein (HDL or "good" cholesterol.) These are the forms in which cholesterol travels in the blood.

LDL is the main source of artery-clogging plaque. HDL actually works to clear cholesterol from the blood.

Triglycerides are another fat in our bloodstream. Research is now showing that high levels of triglycerides may also be linked to heart disease.

High cholesterol itself does not cause any symptoms, so many people are unaware that their cholesterol levels are too high. Therefore, it is important to find out what your cholesterol numbers are. Lowering cholesterol levels that are too high lessens the risk for developing heart disease and reduces the chance of a heart attack or dying of heart disease, even if you already have it.

Some recommend that everyone over age 20 should get their cholesterol levels measured at least once every 5 years. The test that is performed is a blood test called a lipoprotein profile. That includes:

  • Total cholesterol level
  • LDL (the "bad" cholesterol)
  • HDL (the "good" cholesterol)
  • Triglycerides

Here's how to interpret your cholesterol numbers:

Total CholesterolCategory
Less than 200Desirable
200 - 239Borderline High
240 and aboveHigh

 

LDL CholesterolLDL-Cholesterol Category
Less than 100Optimal
100 - 129Near optimal/above optimal
130 - 159Borderline high
160 - 189High
190 and aboveVery high

 

HDL*HDL-Cholesterol Category
60 or moreDesirable - helps to lower risk of
heart disease
Less than 40Major risk factor -- increases the
risk for developing heart disease

*HDL (good) cholesterol protects against heart disease, so for HDL, higher numbers are better.

 

TriglyceridesHDL-Cholesterol Category
Less than 150Normal (desirable)
heart disease
150-199Borderline high

200-499

>500

High

Very high

What Affects Cholesterol Levels?

A variety of factors can affect your cholesterol levels. They include:

  • Diet. Saturated fat, trans fat, carbohydrates, and cholesterol in the food you eat increase cholesterol levels. Reducing the amount of saturated fat, trans fats and sugars in your diet helps lower your blood cholesterol level. Increasing the amount of fiber and plant-derived sterols can also help lower LDL cholesterol.
  • Weight. In addition to being a risk factor for heart disease, being overweight can also increase your cholesterol. Losing weight can help lower your LDL, total cholesterol levels, and triglyceride levels, as well as raise your HDL.
  • Exercise. Regular exercise can lower LDL cholesterol and raise HDL cholesterol. You should try to be physically active for 30 minutes every day.
  • Age and Gender. As we get older, cholesterol levels rise. Before menopause, women tend to have lower total cholesterol levels than men of the same age. After menopause, however, women's LDL levels tend to rise.
  • Heredity. Your genes partly determine how much cholesterol your body makes. High blood cholesterol can run in families.
  • Medical conditions. Occasionally, a medical condition may cause an elevation of cholesterol levels in the blood. These include hypothyroidism (an underactive thyroid gland), liver disease and kidney disease.
  • Medications. Some medicines, like steroids and progestins, may increase "bad" cholesterol and decrease the "good" cholesterol.

The main goals in treating high cholesterol are to lower your LDL levels and lower your risk of cardiovascular disease. To lower cholesterol, eat a heart-healthy diet, exercise regularly, and maintain a healthy weight. Some may also need to take cholesterol-lowering drugs.

Doctors determine your "goals" for lowering LDL based on the number of risk factors you have for heart disease. Based on your risk, your doctor will determine the intensity of LDL reduction you need, and prescribe a medication accordingly.

Many health care providers recommend treating anyone with cardiovascular disease (CVD) with high-dose statin therapy. This includes those with coronary heart disease and those who have had a stroke.

For those who do not have CVD, treatment is determined by your individual risk for developing heart disease. That risk can be estimated using calculators which factor your age, sex, medical history, and other characteristics.  If your risk is high (such as a 7.5 or 10 percent risk of developing CVD over 10 years), your doctor may start you on treatment preventively. They generally keep in mind your preferences towards taking medication in generalFor those people whose risk is unclear, a coronary artery calcium score, which is a screening test looking for calcium (an indication of atherosclerosis) in the arteries, can help determine the need for statins.

For both those who have CVD and those who do not, when the decision is made to start medication, the first choice is usually a statin.

Other special groups who may need treatment:

  • People with high triglyceride levels may benefit if they have other risk factors
  • People with diabetes are at high risk, and an LDL under 100 is recommended for most
  • Among older adults, a healthy, active older adult may benefit from a reduction and be prescribed a medication accordingly.

Cholesterol-lowering drugs include:

  • Statins
  • Cholesterol absorption inhibitors
  • PCSK9 inhibitors
  • Niacin
  • Fibric acid derivatives
  • Bile-acid resins

Cholesterol-lowering medicine is most effective when combined with a healthy diet and exercise program.

Statins 
Statins block the production of cholesterol in the liver itself. They lower LDL, the "bad" cholesterol, and triglycerides and have a mild effect in raising HDL, the "good" cholesterol. These drugs are the first line of treatment for most people with high cholesterol.

Statins carry warnings that memory loss, mental confusion, muscle aches, neuropathy, liver issues, high blood sugar, and type 2 diabetes are possible side effects. It's important to remember that statins may also interact with other medications you take.

Examples of statins include:

Selective cholesterol absorption inhibitors
Ezetimibe (Zetia) works to lower LDL by inhibiting the absorption of cholesterol in the intestines. Vytorin is a newer drug that is a combination of ezetimibe (Zetia) and a statin (simvastatin), and can decrease total and LDL cholesterol and raise HDL levels. There is not sufficient medical evidence to show that ezetimibe prevents heart attacks.

PCSK9 Inhibitors

These drugs are used in people who can’t manage their cholesterol through lifestyle and statin treatments. They block a protein called PCSK9 to make it easier for the body to remove LDL from your blood. They are mainly used in adults who inherit a genetic condition called “heterozygous familial hypercholesterolemia” that makes it hard to bring down their cholesterol level, or for people who have heart disease and need more than a statin. You get them as a shot every 2 weeks.

Examples:

Another option is inclisiran (Leqvio), a PCSK9-siRNA. It’s not broadly used and is recommended for those who are allergic to alirocumab and evolocumab or who have challenges using the pen injector.

Niacin
Niacin is a B-complex vitamin. It's found in food, but is also available at high doses by prescription. It lowers LDL cholesterol and raises HDL cholesterol. These drugs also lower elevated triglycerides. The main side effects are flushing, itching, tingling, and headache, yet aspirin can reduce many of these symptoms. However, speak with your doctor first. Niacin or nicotinic acid, includes the brand names Niacor, Niaspan, or Slo-niacin. Over-the-counter preparations include extended-release, timed-release, and controlled-release. Niacin found in dietary supplements should not be used to lower cholesterol. Your doctor or lipid specialist will let you know if niacin is appropriate for you. Recent research suggests that niacin may improve cholesterol numbers, but may not be associated with prevention of heart attacks.

Bile Acid Sequestrants
These drugs work inside the intestine, where they bind to bile and prevent it from being reabsorbed into the circulatory system. Bile is made largely from cholesterol, so these drugs work by reducing the body's supply of cholesterol, thus lowering total and LDL cholesterol. The most common side effects are constipation, gas, and upset stomach. Examples of bile acid resins include:

Fibrates
Fibrates lower triglyceride levels and can increase HDL and lower LDL cholesterol. The mechanism of action is not clear, but it is thought that fibrates enhance the breakdown of triglyceride-rich particles and decrease the secretion of certain lipoproteins. In addition, they induce the synthesis of HDL.

Examples of fibrates include:

Combination drugs
Some people with high cholesterol achieve the best results with combination drugs. These drugs treat cholesterol problems and are sometimes combined with medications like blood pressure drugs in one pill. Some examples include:

Targeted therapy

The drug bempedoic acid (Nexletol) is a non-statin option for adults with the genetic condition heterozygous familial hypercholesterolemia (HeFH) which causes high cholesterol. It can also be used to help lower cholesterol in those with atherosclerotic cardiovascular disease (ASCVD).

The side effects of cholesterol-lowering drugs include:

  • Muscle aches*
  • Abnormal liver function
  • Allergic reaction (skin rashes)
  • Heartburn
  • Dizziness
  • Abdominal pain
  • Constipation
  • Decreased sexual desire
  • Memory problems

*If you have muscle aches, call your doctor immediately. This could be a sign of a life-threatening condition.

Ask your doctor about the other drugs you are taking, including herbals and vitamins, and their impact on cholesterol-lowering drugs. You should not drink grapefruit juice while taking some types of cholesterol-lowering drugs, as it can interfere with the liver's ability to metabolize these medications. These include:

  • Atorvastatin (Atorvaliq, Lipitor)
  • Lovastatin
  • Simvastatin (Zocor)
  • Telodipine (Plendil)

Some antibiotics may be dangerous when taken with statins. Talk to your doctor.