Cholesterol in and of itself, is a natural function of the human body. Every living being requires a certain amount of fat to exist. Like everything in nature, it only becomes a problem when there is an imbalance.
The processing of fat begins when it gets absorbed in the intestines. From there it heads to the liver. The fat requires a delivery system to the rest of the body to be used immediately but also to be stored in fat cells for future use.
In order for the fat to enter the delivery system, while it is in the liver it is split into two different types of fat, cholesterol and triglycerides.
Once this transformation takes place, the two types of fat (cholesterol and triglycerides) are packed into vehicles for carrying the fat to the fat cells throughout the body using the bloodstream. These vehicles are called lipoproteins.
There are three types of lipoproteins:
1. Very Low Density Lipoproteins (VLDL)
2. Low Density Lipoproteins (LDL)
3. High Density Lipoproteins (HDL)
Under normal circumstances, the bloodstream does a very efficient job of carrying the LDL and HDL Lipoproteins throughout the body.
Cholesterol is a waxy, fat like substance that presents itself naturally in cell walls and membranes everywhere in your body. Your body uses cholesterol to produce many hormones. It also uses it to produce vitamin D and the bile acids that help to digest fat. Where problems arise is when there is an over abundance of cholesterol in your bloodstream. The cholesterol deposited by the LDL leads to a narrowing of the blood vessels. If this occurs, the excess can be deposited in the arteries of the heart which could result in stroke or heart disease. This is called atherosclerosis. This is why LDL is known as “bad cholesterol.”
HDL usually collects the bad cholesterol and takes it back to the liver. That’s why HDL is known as “good cholesterol.”
Cholesterol is not the only cause of heart disease, but it is a contributing factor. Here’s how it works.
Cholesterol can only attach to the inner lining of the artery if it has been damaged. Once the lining of the artery is damaged, white blood cells rush to the site followed by cholesterol, calcium and cellular debris. The muscle cells around the artery are altered and also accumulate cholesterol. The fatty streaks in the arteries continue to develop and bulge into the arteries. This cholesterol “bulge” is then covered by a scar that produces a hard coat or shell over the cholesterol and cell mixture. It is this collection of cholesterol that is then covered by a scar that is called “plaque.” The buildup of plaque narrows the space in the arteries through which blood can flow, decreasing the supply of oxygen and nutrients. This cuts down the supply of blood and oxygen to the tissues that are fed by that blood vessel.
The elasticity of the blood vessel is reduced and the arteries’ ability to control blood pressure is compromised. If there is not enough oxygen carrying blood passing through the narrowed arteries, the heart may give you a pain that is called angina. The pain usually happens when you exercise because at that time your heart requires more oxygen. Usually it is felt in the chest or the left arm and shoulder, although it can happen without any symptoms at all.
Plaque can vary in size as well as shape. All through the coronary arteries you can find many small plaques that cover less than half of an artery opening. Some of these plaques are completely invisible in the tests that doctors use to identify heart disease.
The medical community used to think that the primary concern was the larger plaques. They thought these posed a greater threat because of their size and that they were more likely to cause a complete blockage of the coronary arteries. While it is true that the larger plaques are more likely to cause angina, it is the smaller plaques that are packed with cholesterol and covered by scars that are more dangerous. They are considered unstable and prone to ruptures or bursting releasing their load of cholesterol into the bloodstream. This causes immediate clotting within the artery. If the blood clot blocks the artery totally, it will stop the blood flow and a heart attack occurs. The muscle on the farter side of the occurring clot fails to get the oxygen it needs and begins to die. This kind of damage can be permanent.
DIAGNOSING CHOLESTEROL
Unfortunately, most people aren’t even aware they have atherosclerosis until they have a heart attack or stroke. It is possible to have up to 80 percent closure of the arteries without ever feeling a single symptom!
Most people begin to develop cholesterol driven atherosclerosis as children and it’s unusual if you find an adult in the United States who does not have some degree of atherosclerosis.
Diagnosing cholesterol levels require a simple blood test to determine the levels of LDL and HDL. Cholesterol tests can be tricky, however. Simple screening that is done without “fasting,” measures only the total cholesterol and the HDL, the “good” cholesterol. It will give you a ballpark figure, but far from accurate. The complete test is called a “lipid profile,” and even that can vary from test to test. This test will measure total cholesterol, HDL, LDL and triglycerides.
For truly accurate numbers, you should not eat, or drink anything other than water for 12 hours before testing. Vigorous exercise should be avoided for 24 hours before testing and you need to make certain that whoever tests you is made aware of any medications you may be taking as they will also affect the results.
Okay, now that you have accurate numbers, what do they mean? Before we discuss the numbers and their meanings, we need to clarify some terminology.
Dietary cholesterol means the cholesterol that you eat. The American Heart Association recommends no more than 300 milligram per day. Most food labels in the United States list cholesterol. The three terms, blood cholesterol, serum cholesterol and total cholesterol mean the same thing – the total cholesterol in your body. This is what is measured when you have a cholesterol test. Your test results will come in with three numbers:
1. HDL Cholesterol
2. LDL Cholesterol
3. Total Cholesterol
For total cholesterol the National Cholesterol Education Program classifies levels below 200 milligrams/dl (milligrams per deciliter) as “desirable.” A level between 200 and 239 is “borderline high.” Anything over 240 is “high.”
Triglyceride levels over 400 milligrams/dl are considered “high” and levels over 1,000 milligrams/dl are considered “very high.”
For LDL, the desirable level is less than 130 milligrams/dl. The “borderline high” level is 130 to 159. the “high risk” level is 160 and above.
Higher is better for HDL. For HDL, the numbers are lower because there is less HDL in the blood. Anything lower than 35 milligrams/dl is considered “high risk.” If your HDL is very high, say over 60, your risk of heart disease is reduced.
The LDL, however, is the “bad” cholesterol and the most important factor in predicting heart attack. For LDL, lower is better preferably less than 160. It’s best to keep the level around 130.
CAUSES
If you recall, we mentioned that cholesterol can only attach to the inner lining of the artery if it has been damaged. How does that damage occur?
Evidence points to “free radical” damage as being one of the culprits of arterial wall damage. Free radicals are found all around us. They are highly reactive substances like polluted air, radiation, tobacco smoke, herbicides, and naturally within our own bodies as an offshoot of regular metabolic processes. Free radicals attack and damage cells altering normal cell activity. You see it around you every day causing metal to rust and fruit to spoil. This is why we take anti-oxidants like vitamins C, E, beta-carotene and selenium, to combat the attack of free radicals. Heredity plays a role in high cholesterol. Your genes can influence your LDL by affecting how fast it is made and removed from your blood. There is one particular form of inherited high cholesterol that will often lead to early heart disease. It is called familial “hypercholesterolemia” and can play a role in 1 of 500 people.
Weight is a factor in determining your LDL. If you have a high LDL level and are overweight, losing those pounds may help you to lower it. Additionally, losing weight also helps to lower triglycerides and raise your HDL.
Age and sex should be considered as well. Women, before menopause, usually have total cholesterol levels that are lower than men. This changes as men and women age. Levels will rise until reaching age 60 to 65. For women, menopause can cause an increase in LDL and a decrease in HDL. After the age of 50 women often have higher total cholesterol levels than men of the same age.
Alcohol plays an odd role in cholesterol levels. It increases HDL but at the same time it does not lower LDL. The medical community does not know for certain whether alcohol reduces the risk of heart disease. We know that too much alcohol can damage the liver and heart muscle, lead to high blood pressure and raise triglycerides. There are just too many other risks to even consider the use of alcoholic beverages used as a way to prevent heart disease just because it increased the HDL. Stress and personality may contribute to heart disease. Associating a certain type of personality and heart disease has been suggested for many years. This goes back to the “Type A” and “Type B” personality study conducted in 1959.
Type A behavior generally manifests in a chronic sense of time, urgency, aggressiveness and striving for achievement. Type A people will drive themselves to meet specific deadlines which are most often self-imposed. They have feelings of being constantly under pressure and often multi-task to the point of doing two or three things at one time. To say that Type A people are “driven” is an understatement. They consider themselves indispensable. All of these traits add up to a state of constant stress Over the long term, stress has shown to raise blood cholesterol levels. The way it does this is by affecting habits. An example is over indulging in fatty foods as a way of consoling themselves when people are under stress. The saturated fat and cholesterol in these foods contribute to high levels of blood cholesterol.
Type B behavior is characterized by just the opposite set of traits. Type B people are less preoccupied with achievement, less rushed and generally more easy going people.
They don’t allow themselves to be rushed nor have any particular pressure regarding deadlines. They are less prone to angry outbursts and seem to be better equipped to making distinctions between work and play. Studies completed over a period of eighteen months to two years with a group of both Type A and Type B people, indicated that Type A participants had a 31 percent increased risk of developing heart disease.
This was further substantiated by the discovery of more deposits of plaque in the coronary arteries of Type A people. Type A behavior also appears to show an association with other risk factors like smoking, higher fat levels, increased secretion of adrenaline. All of which increases the oxygen requirement of the heart muscles and releasing fatty acids from the body fat. It is important to note that there are not two different types of people. Each person is an individual and sorting them into specific categories do not properly identify them.
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