Sunday, January 6, 2008

Cholesterol Reduction-A

Elevated cholesterol is associated with a greater-than-normal risk of atherosclerosis and cardiovascular disease. While antioxidants can inhibit cholesterol from oxidizing onto the linings of the arteries, knowing and controlling your cholesterol levels is still an important step in preventing cardiovascular disease.

Estimates are that 52% of the total population have cholesterol levels of 200 mg/dL, and about 21% have levels of 240 or above. In adults, total cholesterol levels from 200 to 239 mg/dL are considered borderline-high, while levels above 240 are considered dangerously high. Knowing cholesterol numbers can allow a person to manage "fat intake," which has other benefits, such as lowering one's risk of various cancers caused by fat-soluble toxins.

During the past 20 years, deaths from heart disease have gone down 33% in the United States saving as many as 250,000 lives each year! This is because people are beginning to learn about and take the proper precautions to prevent and treat heart problems. Keeping cholesterol levels in the safest range (between 180 and 200 mg/dL) is one way of statistically reducing your risk of suffering a heart attack or stroke.

Types of Cholesterol, and the Impact on Your Health

Low Density Lipoprotein (LDL)

Low density lipoprotein (LDL) is called the "bad" form of cholesterol. LDL carries most of the cholesterol in the blood, and the cholesterol from LDLs is the main source of damaging accumulation and blockage in the arteries. Thus, the more LDLcholesterol you have in your blood, the greater your risk of disease. If you have coronary heart disease (CHD) and your LDL is higher than 100 mg/dL, your cholesterol may well be too high for you.

High Density Lipoprotein (HDL)
High density lipoprotein (HDL) is called the "good" form of cholesterol. HDL picks up and transports cholesterol in the blood back to the liver, which leads to its elimination from the body. HDL can help keep LDL cholesterol from building up in the walls of the arteries. If your level of HDL cholesterol is below 35 mg/dL, you are at substantially higher risk for CHD. The higher your HDL cholesterol level, the better. The average HDL-cholesterol for men is about 45 mg/dL, and for women it is about 55 mg/dL.

Triglycerides
Triglycerides are a form of fat carried through the bloodstream. Most of your body's fat is in the form of triglycerides stored in fat tissue. Only a small portion of your triglycerides are found in the bloodstream. High blood triglyceride levels alone do not cause atherosclerosis. But lipoproteins that are rich in triglycerides also contain cholesterol, which causes atherosclerosis in many people with high triglycerides. So high triglycerides may be a sign of a lipoprotein problem that contributes to CHD.

Serum (blood) cholesterol levels are affected not only by what you eat, but also by how quickly your body creates LDL cholesterol and eliminates it. Most people manufacture all the cholesterol they need in their liver, and it is not necessary to obtain any surplus cholesterol from food.

Patients with coronary artery disease typically have too high a level of LDL cholesterol in their blood. Multiple factors help determine whether your LDL cholesterol level is high or low. The factors discussed next are the most important:

The following factors are the most important:

Heredity
Your genes control how high your LDL cholesterol is by affecting how fast LDL is made and removed from the blood. One specific form of inherited high cholesterol is familial hypercholesterolemia, which often leads to early CHD. Even if you do not have a specific genetic form of high cholesterol, genes play a role in affecting your LDL cholesterol level.

What you eat
Saturated fat, found mostly in foods that come from animals, increases your LDL cholesterol level more than anything else in your diet. Dietary cholesterol also plays a part. The average American man consumes about 360 mg of cholesterol a day; the average woman, between 220 and 260 mg. Eating too much saturated fat and cholesterol-rich foods such as eggs is the main reason for high levels of cholesterol and a high rate of heart attacks in the United States according to the Centers for Disease Control. Reducing the amount of saturated fat and cholesterol you eat is a very significant step in reducing blood cholesterol levels.

Here are the 1999 dietary recommendations from the American Heart Association:

"Cholesterol is found in meat, poultry, seafood and dairy products. Foods from plants-such as fruits, vegetables, vegetable oils, grains, cereals, nuts, and seeds-don't contain cholesterol. Egg yolks and organ meats are high in cholesterol. Shrimp and crayfish are somewhat high in cholesterol. Chicken, turkey, and fish contain about the same amount of cholesterol as do lean beef, lamb and pork."

As can be seen from the above recommendations, it is hard to avoid consuming foods that cause cholesterol to build up in the blood.

Weight
Excess weight tends to increase LDL cholesterol level. If you are overweight and have a high LDL cholesterol level, losing weight may help lower it. Weight loss also helps to lower triglycerides and raise HDL. Conversely, it is now accepted that even small increases in weight may increase cholesterol and the general risk of cardiovascular disease.

Physical activity/exercise

Frequent physical activity may lower LDL cholesterol and raise HDL cholesterol levels.

Age and sex
Before menopause, women usually have total cholesterol levels that are lower than those of men the same age. As women and men get older, their blood cholesterol levels rise until about 60 to 65 years of age. In women, menopause often causes an increase in LDL cholesterol and a decrease in HDL cholesterol level, and after the age of 50, women often have higher total cholesterol levels than men of the same age.

Alcohol
Alcohol intake increases HDL cholesterol but does not lower LDL cholesterol. Drinking too much alcohol can damage the liver and heart muscle, lead to high blood pressure, and raise triglycerides. Because of the risks, doctors don't recommend alcoholic beverages as a way to prevent CHD, yet the consumption of just one glass of red wine or other alcoholic beverage statistically reduces the risk of heart attack and stroke without causing other health problems for most people.

Stress
Stress over the long term has been shown in several studies to raise blood cholesterol levels. One way that stress may do this is by affecting your habits. For example, when some people are under stress, they console themselves by eating fatty foods. The saturated fat and cholesterol in these foods contribute to higher levels of blood cholesterol.

Who's at Risk?
"At risk" cholesterol numbers are considered to be anything above 200 mg/dL for total serum cholesterol with the caveat that the dangerous LDL cholesterol (low density lipoprotein) number be less than 100 mg/dL. HDL cholesterol (high density lipoprotein), the aptly named "good" cholesterol, can be increased using specific nutrient supplements and by limiting total serum cholesterol intake. If your HDL is less than 35 mg/dL, your physician will try to help you increase it, while lowering LDL cholesterol.

Here's a fact for you to consider! A person with a total serum cholesterol number of 260 mg/dL increases his or her chance of a heart attack by 500% (Annals of Internal Medicine (United States), 1979).

Cholesterol is a vital substance that is synthesized by the liver and other bodily tissues. The body uses cholesterol as a building block for essential organic molecules such as steroid hormones, cell membranes, and bile acids. Our bodies produce between 500 to 1000 mg total serum cholesterol each day, and this amount is added to the typical American's diet, which may contain an additional 500 to 1000 mg a day of additional cholesterol-half of which is absorbed into the body. Therefore, the total elimination of all cholesterol from dietary sources may not be enough for some people, and over time they may face elevated cholesterol levels and require additional measures to control or reduce cholesterol (Heart Disease, Preventive Medicine, 1992).

Source of risk factors: Columbia and Boston Universities, 1999.

Cholesterol and the Threat of Unstable Plaque
Cholesterol is a major ingredient of the plaque that collects in the coronary arteries and causes CHD, so it is important to understand how plaques develop. Excess cholesterol is deposited in the artery walls as it travels through the bloodstream. Then special cells in the artery wall gobble up this excess cholesterol, creating a "lump" in the artery wall. This cholesterol-rich "lump" then is covered by a scar that produces a hard coat or shell over the cholesterol and cell mixture. It is this collection of cholesterol covered by a scar that is called plaque.

The plaque buildup narrows the space in the coronary arteries through which blood can flow, decreasing the supply of oxygen and nutrients to the heart. If not enough oxygen-carrying blood can pass through the narrowed arteries to reach the heart muscle, the heart may respond with a pain called angina. The pain usually happens with exercise when the heart needs more oxygen. It is typically felt in the chest or sometimes in other places like the left arm and shoulder. However, this same inadequate blood supply may cause no symptoms. Cardiovascular disease is often a "silent" disease, until something happens.

Plaques come in various sizes and shapes. Throughout the coronary arteries many small plaques build themselves into the walls of the arteries, blocking less than half of the artery opening. These small plaques are often invisible on many of the tests doctors use to identify coronary heart disease. It used to be thought that the most dangerous plaques and the ones most likely to cause total blockage of coronary arteries were the largest ones. The largest plaques are in fact the ones most likely to cause angina. However, small plaques that are full of cholesterol but not completely covered by scar are now thought to be very unstable and more likely to rupture or burst, releasing their cholesterol contents into the bloodstream.

When this happens, it precipitates blood clotting inside the artery. If the blood clot totally blocks the artery, it reduces or stops blood flow, and a heart attack occurs. The muscle on the far side of the blood clot does not get enough oxygen and begins to die. The damage can be permanent.

Lowering your blood cholesterol level can slow, stop, or even reverse the buildup of plaque. Cholesterol lowering can reduce your risk of a heart attack by lowering the cholesterol content in unstable plaques to make them more stable and less prone to rupture. This is why lowering your LDL cholesterol is such an important way to reduce your risk for having a heart attack. Even in people who have had one heart attack, the chances of having future attacks can be substantially reduced by cholesterol reduction.

One of the best methods of reducing cholesterol is through dietary modification (see Dash Diet in Hypertension protocol). Supplements offer excellent synergistic benefits to augment dietary measures.

The Benefits of Lowering Cholesterol
A 5-year clinical trial with over 4400 patients with heart disease found that lowering cholesterol can prevent heart attacks and reduce death in men and women who already have heart disease and high cholesterol. Researchers say that the following benefits could be expected if physicians were to treat their heart disease patients for the same 5-year period and lower cholesterol to the same extent.

For every 1000 patients,

Forty people would be saved out of the 90 who would otherwise die from heart disease.
Seventy of the expected 210 nonfatal heart attacks would be avoided.
Heart procedures such as bypass surgery would be avoided in 60 of the 210 patients who would be expected to need theseprocedures.
The most recent report of the National Cholesterol Education Program identified low HDL cholesterol as a coronary artery disease risk factor and recommended that "all healthy adults be screened for both total cholesterol and HDL cholesterol levels" (Am. J. Cardiol., Nov. 1998, 82:9A, 13Q-21Q).

Landmark clinical studies in the past several years have demonstrated diminished mortality and first coronary events following lowering of low density lipoprotein (LDL) cholesterol. The Framingham Heart Study (a long-term research study) produced compelling evidence indicating that a low level of HDL cholesterol was an independent "predictor" of coronary artery disease (CAD).

Many community health organizations, local drug stores, and health food stores regularly provide low-cost or free cholesterol screening for those interested in monitoring their serum cholesterol. Seek the advice of a competent physician experienced in cholesterol management using dietary modification and nutritional supplements. A physician with this kind of background can also help with the substitution of nutrient-based cholesterol-reduction plans which may allow the reduction or elimination of prescription drugs.

If you already have high blood pressure as well as high blood cholesterol (and many people do), your physician may also tell you to cut down on sodium or salt. As long as you are working on getting your blood cholesterol number down, this is a good time to work on your blood pressure, too.

Traditional Therapies

HMG CoA Reductase Inhibitors

Drugs that inhibit the enzyme HMG-CoA reductase are referred to as "statins." These drugs lower cholesterol by slowing down the production of cholesterol and by increasing the liver's ability to remove the LDL cholesterol already in the blood.

The latest introduction to the powerful group of lipid-lowering drugs known as statins, or HMG reductase inhibitors, is atorvastatin (Lipitor). It is the only statin approved for the reduction of triglycerides as well as total and LDL cholesterol. It reduces LDL by 40 to 60%, triglycerides by 20 to 40%, and raises HDL cholesterol by 5 to 10%, changes which may be bigger than those produced by other statins. It can be taken once a day, at any time of day, and the recommended dose range is from 10 to 80 mg a day. Atorvastatin provides the lowest cost per percentage of LDL cholesterol reduction of available statins. Other available statins, which primarily reduce LDL cholesterols are cerivastatin (Baychol), fluvastatin (Lescol), lovastatin (Mevacor), pravastatin (Pravachol), and simvastatin (Zocor).

Additional drugs that are commonly prescribed and approved for lowering elevated triglyceride levels are gemfibrozil and clofibrate. These drugs may be prescribed alone or in combination with other drugs. These triglyceride-lowering drugs have toxic side effects that cause many people to avoid them.

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