In the next paragraphs you will find concepts and definitions of important terms related to cardiovascular health.

In addition, you will find a comprehensive but simple-to-understand explanation of how blood lipids—low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglyceride—and free radicals affect your risk of developing Cardiovascular Disease (CVD). If you are not familiar with the subject, we suggest you take a few minutes to read this important information.

Otherwise, if you are familiar with blood lipids, cholesterol, and the causes of CVD, you may want to click here to find out which nutrients help in the promotion of cardiovascular health. If you are pressed for time and want to read only a summary, we then suggest you skip to the section on this page entitled “What You Must Know about Cholesterol.”

Blood Lipids—Basic Concept

Cholesterol is a waxy, fat-like substance carried in the bloodstream, and it comes from two sources. It is produced by an enzyme in our body (a liver enzyme called HMG-CoA reductase), and it also comes from the food we eat. The human body needs some cholesterol because it is essential to form cell membranes, some hormones, and other needed tissue. But a high level of cholesterol in the blood (hypercholesterolemia) is a major risk factor for Cardiovascular Disease, which leads to heart attacks and stroke, the number one cause of death in several countries around the world.

Many people know that the healthy function of the brain, heart, cardiovascular system, and most organs depends on the unobstructed flow of blood for the delivery of oxygen and nutrients and the removal of harmful metabolites and waste. Unfortunately, fewer people understand that cholesterol and other fats cannot dissolve in the blood; they have to be transported in the bloodstream by special carriers of lipids and proteins called lipoproteins.

There are several kinds of lipoproteins. The two most important ones are low-density lipoprotein (LDL), which is the major carrier of cholesterol in the blood, and high-density lipoprotein (HDL), which carries one-third to one-fourth of blood cholesterol. There are other lipoproteins, such as very-low-density lipoprotein (VLDL) that are often ignored but are also important in determining the level of risk of developing CVD. Only a medical doctor well trained in internal medicine can determine the influence of each of the lipoproteins in your particular risk of developing CVD.

When too much LDL is circulating in our bloodstream, it can slowly build up within the walls of the arteries feeding the heart and the brain. Together with other substances, LDL can form a thick, hard deposit (plaque) that can clog the arteries, a condition known as atherosclerosis. It is very important to prevent LDL from depositing in the walls of your blood vessels because sometimes a small portion or clot of this plaque can tear loose from the blood vessel wall and then be carried away by the blood. This clot (or thrombus) can eventually act as a plug in an artery, blocking the flow of blood and oxygen to part of the heart muscle and causing a heart attack or blocking the flow of blood and oxygen to part of the brain, producing a stroke. A high level of LDL reflects an increased risk of heart disease, and that is why LDL is often referred to as “bad” cholesterol. Conversely, scientific and medical research has determined that HDL carries cholesterol away from the arteries and back to the liver, where it is processed, and therefore it removes excess cholesterol from atherosclerotic arteries, slowing the growth of plaque. HDL is therefore known as “good” cholesterol because a high level of HDL seems to protect against heart attack.

Important: To actively manage your risk of developing Cardiovascular Disease, your first and most important goal should be to closely monitor your bloodstream levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), and other blood lipids such as VLDL and triglyceride. Your doctor should be part of this process, and he or she should help you achieve that goal.

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How LDL Cholesterol Obstructs the Circulatory System

LDL cholesterol must be “oxidized” by free radicals before it can form plaque and create artery blockage. A free radical is a molecular fragment that has an unpaired electron. Highly reactive, free radicals search to regain a full complement of electrons. Whenever LDL particles are exposed to these unstable molecules, the LDL particles are oxidized. Immediately the LDL becomes stickier, a quality that increases risk of formation of a blood clot. In the process, an oxidized LDL particle becomes toxic to the human body. Non-oxidized LDL is recognized as “self,” or non-threatening, by the body’s immune system. But oxidized LDL is so changed that our immune system identifies it as “non-self,” or foreign and potentially dangerous. To safeguard the body from this possible hazard, the immune system’s large scavenger cells (called macrophages) engulf and swallow up all oxidized LDL. By a process not yet fully understood, the LDL-bloated macrophages are lured into tiny cracks or injuries in artery walls, where they become embedded and protrude out, partially occluding the artery and causing atherosclerosis.

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What You Must Know about Cholesterol

Cholesterol is a type of fat (lipid) found in the blood, and it comes from two sources. It is produced by an enzyme in our body (a liver enzyme called HMG-CoA reductase), and it also comes from the food we eat. Cholesterol is “transported” in the bloodstream by different types of lipoproteins. The best-researched lipoproteins are high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very-low-density lipoprotein (VLDL). High levels of LDL and VLDL (commonly referred as bad cholesterol) cause the formation of plaque in the arteries. Over time, the buildup of plaque causes narrowing of the arteries and results in reduced flow of blood and oxygen to the brain, heart, and other organs. A high level of LDL and VLDL are then considered the main cause of Cardiovascular Disease (CVD).

Researchers have determined that genetic predisposition—family history of Cardiovascular Disease represented by the tendency to produce too much cholesterol in the liver—and the arithmetic ratio of total cholesterol (TC) to good cholesterol (HDL) show good predictability of who will develop CVD. The ratio is called the cardiac risk ratio (CRR), and it is obtained by dividing the total cholesterol (TC) level (an aggregate of several blood lipid levels) by the HDL (good cholesterol) level (TC/HDL). In managing the risk of developing CVD, the main goal should always be to keep the CRR below 5 and ideally under 3.5.

A desirable level of total cholesterol should be under 200 milligrams per deciliter (mg/dL) and a desirable level of LDL under 100 mg/dL. If your total cholesterol level is in the borderline-high range (between 200 and 239 mg/dL), dietary changes, exercise, consumption of nutrients, and a cholesterol dietary supplement should bring the levels down to a desirable level.

Keep in mind that reading and understanding cholesterol levels is very complex, especially since many different types of blood lipids (HDL, LDL, VLDL, and triglyceride, among others) have to be taken into consideration. The most important fact to remember is that if your total cholesterol level is above 240 mg/dL or if your LDL level is above 100 mg/dL, you should be in a cholesterol-reducing regimen supervised by an internal medicine doctor you trust.

If the information presented on this page seems too complicated or overwhelming, just try to remember these simple facts:

To help in the prevention of Cardiovascular Disease, try to maintain a total cholesterol (TC) level under 200 mg/dL and an LDL (bad cholesterol) level under 100 mg/dL. Also try to maintain your total cholesterol to good cholesterol ratio TC/HDL under 3.5.

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What Is Triglyceride and How Does It Relate to Cholesterol?

Triglyceride is an important part of lipid metabolism—the use of lipids within the body. In general, triglyceride is thought to cause less atherosclerosis than other lipids, such as LDL. Multiple studies have suggested that Cardiovascular Disease does not correspond to triglyceride levels; however, limited other studies disagree with this. It is generally thought that triglyceride constitutes an independent risk factor for atherosclerosis in women but not in men. There is an inverse relationship between blood triglyceride levels and HDL levels that tends to confuse the issue. This means that when the triglyceride level tends to be increased, the HDL level tends to be lower than normal. Therefore, an elevated triglyceride level (and thus decreased HDL level) may cause atherosclerosis indirectly. Actually, we understand only a fraction of everything there is to know about lipids. Of all the known lipids, triglyceride is the least studied and understood.

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What is Familial Hypercholesterolemia (FH)?

FH patients have high blood concentrations of LDL cholesterol due to a genetic disorder which prevents proper metabolism of LDL-particles. These patients experience a markedly increased risk of premature cardiovascular diseases (CVD) and CVD-related death. Familial hypercholesterolemia can be present in two forms: homozygous (hoFH), where the same defective gene is inherited from both parents, or heterozygous (heFH), where the defective gene is inherited from only one parent so that some function is preserved. The homozygous form is a very rare condition estimated to affect approximately one in a million people. Children with hoFH are at high risk for early coronary events and sudden death as young as age one. HeFH is more common, with a prevalence of approximately one in 500, and patients with heFH also experience elevated LDL cholesterol and are at high risk for early coronary events. For undiagnosed or untreated heFH, the cumulative risk of a coronary heart disease (CHD) by age 60 years is 60-85% among men and 30-50% among women, with a mean age of early-stage diagnosis of approximately 47 years.

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Natural Alternatives to Promote Healthy Levels of Cholesterol

David Heber, M.D., Ph.D., states in his book Natural Remedies for a Healthy Heart:

It has been estimated that 25 percent of the patients who take cholesterol-lowering prescription drugs and follow a low-fat, low-cholesterol diet do not achieve adequate reductions in their cholesterol levels. In many patients, this is due to the presence of elevated triglyceride levels, so physicians must add a second or third drug to lower triglyceride as well. Every day, cardiologists are discovering new treatments for patients with severe heart disease. These new treatments are not an argument against prevention. On the contrary, both are needed. I believe that prevention can be both highly technical and natural by combining a scientific understanding of what is going on in each patient with the use of natural therapies.

Penny M. Kris-Etherton, Ph.D., of Pennsylvania State University, states:

Clearly we are entering an exciting era in which we will likely identify novel ways to lower risk of cardiovascular disease and other chronic diseases with diet.

There are several divergent views on how to effectively promote and maintain healthy cholesterol levels in your bloodstream and therefore reduce the risk of heart disease. However, most experts agree that nature provides ways to complement dietary and lifestyle changes to improve cardiovascular health.

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