Cholesterol and Preventive Measures

What is Cholesterol?
Cholesterol is a waxy, fat-like compound that belongs to a class of molecules called steroids. It's found in many foods, in your bloodstream and in all your body's cells. If you had a handful of cholesterol, it might feel like a soft, melted candle. Cholesterol is essential for:
· Formation and maintenance of cell membranes (helps the cell to resist changes in temperature and protects and insulates nerve fibers)
· Formation of sex hormones (progesterone, testosterone, estradiol, cortisol)
· Production of bile salts, which help to digest food
· Conversion into vitamin D in the skin when exposed to sunlight.

Most of the body's cholesterol is manufactured in the liver

The formation of cholesterol involves a series of complicated biochemical reactions that begin with the widespread 2-carbon molecule Acetyl CoA: Acetyl CoA (C2) --> mevalonate (C6) --> isopentenyl pyrophosphate (C5) --> squalene (C30) --> cholesterol (C27). Cholesterol is made primarily in your liver (about 1,000 milligrams a day), but it is also created by cells lining the small intestine and by individual cells in the body.

Functioning of Cholesterol
Have you ever been about to take a big bite of your triple chocolate fudge cake when someone leaned over and said "you better watch your cholesterol"? That's happening to all of us more frequently. According to The American Heart Association, high levels of cholesterol are a risk factor for coronary heart disease, the nation's number one killer. Over 100 million Americans have cholesterol levels that exceed the recommended total and 20 percent of Americans have levels that are considered high.

You can check nutrition labels, like this one from a can, for cholesterol information.

What we don't often hear is the important fact that some cholesterol is vital to human life. In this article, we will take a look at cholesterol, both why it is needed for normal human--and animal--functions and why at high levels and in many individuals, it can be deadly.
Blood Cholesterol vs. Dietary Cholesterol
It may surprise you to know that our bodies make all the cholesterol we need. When your doctor takes a blood test to measure your cholesterol level, the doctor is actually measuring the amount of circulating cholesterol in your blood, or your blood cholesterol level. About 85 percent of your blood cholesterol level is endogenous, which means it is produced by your body. The other 15 percent or so comes from an external source -- your diet. Your dietary cholesterol originates from meat, poultry, fish, seafood and dairy products. It's possible for some people to eat foods high in cholesterol and still have low blood cholesterol levels. Likewise, it's possible to eat foods low in cholesterol and have a high blood cholesterol level.
So, why is there so much talk about cholesterol in our diet? It's because the level of cholesterol already present in your blood can be increased by high consumption of cholesterol and saturated fat in your diet. This increase in dietary cholesterol has been associated with atherosclerosis, the build-up of plaques that can narrow or block blood vessels. If the coronary arteries of the heart become blocked, a heart attack can occur. The blocked artery can also develop rough edges. This can cause plaques to break off and travel, obstructing blood vessels elsewhere in the body. A blocked blood vessel in the brain can trigger a stroke.
The average American man eats about 360 milligrams of cholesterol a day; the average woman eats between 220 and 260 milligrams daily. So how are we doing? The American Heart Association recommends that we limit our average daily cholesterol intake to less than 300 milligrams. Obviously, people with high levels of cholesterol in the blood should take in even less.
Good vs Bad Cholesterol
Comments about "good" and "bad" cholesterol refer to the type of carrier molecule that transports the cholesterol. These carrier molecules are made of protein and are called apoproteins. They are necessary because cholesterol and other fats (lipids) can't dissolve in water, which also means they can't dissolve in blood. When these apoproteins are joined with cholesterol, they form a compound called lipoproteins. The density of these lipoproteins is determined by the amount of protein in the molecule. "Bad" cholesterol is the low-density lipoprotein (LDL), the major cholesterol carrier in the blood. High levels of these LDLs are associated with atherosclerosis. "Good" cholesterol is the high-density lipoprotein (HDL); a greater level of HDL--think of this as drain cleaner you pour in the sink--is thought to provide some protection against artery blockage.
A high level of LDL in the blood may mean that cell membranes in the liver have reduced the number of LDL receptors due to increased amounts of cholesterol inside the cell. After a cell has used the cholesterol for its chemical needs and doesn't need any more, it reduces its number of LDL receptors. This enables LDL levels to accumulate in the blood. When this happens, the LDLs begin to deposit cholesterol on artery walls, forming thick plaques. In contrast, the HDLs--the "good" guys--act to remove this excess cholesterol and transport it to the liver for disposal.
A third group of carrier molecules, the very low-density lipoproteins (VLDL) are converted to LDL after delivering triglycerides to the muscles and adipose (fat) tissue.
The levels of HDL, LDL and total cholesterol are all indicators for atherosclerosis and heart attack risk. People who have a cholesterol level of 275 or greater (200 or less is desirable) are at significant risk for a heart attack, despite a favorable HDL level. In addition, people who have normal cholesterol levels but low HDL levels are also at increased risk for a heart attack.
Risk Factors
There are a number of factors that influence a person's cholesterol levels. They include diet, age, weight, gender, genetics, diseases and lifestyle.
Diet

There are two dietary factors associated with increases in blood cholesterol levels:
Eating foods that are high in saturated fats, even if the fats themselves do not contain cholesterol. (These include foods containing high levels of hydrogenated vegetable oils, especially palm and coconut oils, avocados and other high-fat foods of vegetable origin).
Eating foods containing high levels of cholesterol. (This group includes eggs and red meat--the most maligned of the cholesterol culprits--as well as lard and shrimp. These foods can significantly raise blood cholesterol levels, especially when combined with foods that are high in saturated fat).
It's important to note that only foods of animal origin contain cholesterol. Lack of awareness of this fact has led to some confusing labels at the grocery store. For example, some items that are high in saturated fats from plant sources bear labels claiming that they are 100 percent cholesterol free. The statement may be true, but it's generally misleading because it implies that the product is definitely beneficial to your health.
Age

The blood levels of cholesterol tend to increase as we age--a factor doctors consider when deciding treatment options for patients with certain cholesterol levels.
Weight

People who are overweight are more likely to have high blood cholesterol levels. They also tend to have lower HDL levels. The location of the excess weight also seems to play a role in cholesterol levels. A greater risk of increased cholesterol levels occurs when that extra weight is centered in the abdominal region, as opposed to the legs or buttocks.
Gender

Men tend to have higher LDL levels and lower HDL levels than do women, especially before age 50. After age 50, when women are in their post-menopausal years, decreasing amounts of estrogen are thought to cause the LDL level to rise.
Genetics

Some people are genetically predisposed to having high levels of cholesterol. A variety of minor genetic defects can lead to excessive production of LDLs or a decreased capacity for their removal. This tendency towards high cholesterol levels is often passed on from parents to their children. If your parents have high cholesterol, you need to be tested to see if your cholesterol levels are also elevated.
Diseases

Diseases such as diabetes can lower HDL levels, increase triglycerides and accelerate the development of atherosclerosis. High blood pressure, or hypertension, can also hasten the development of atherosclerosis, and some medications used to treat it can increase LDL and triglycerides and decrease HDL levels.
Lifestyle
Factors that negatively affect cholesterol levels also include high levels of stress, which can raise total cholesterol levels, and cigarette smoking, which can lower a person's HDL level as much as 15 percent. On the other hand, strenuous exercise can increase HDL levels and decrease LDL levels. Exercise also can help reduce body weight, which, in turn, can help reduce cholesterol. Recent research has shown that moderate alcohol use (one drink per day for women, two drinks a day for men) can raise HDL cholesterol and therefore reduce the risk of heart attack. Despite such research, it is difficult to recommend the habitual use of alcohol, because there are also negative health consequences associated with alcohol use and a high potential for abuse.
Always remember that risk factors for high cholesterol and cardiovascular disease don't exist in a vacuum--they tend to amplify each other. Reducing the risk of a cardiovascular disease involves eliminating all of the risk factors that we can control and seeking medical advise for those we can't.
Testing and Prevention
You should get your cholesterol tested every three to five years, more often if you have high cholesterol levels. Please refer to the table below for guidelines for total cholesterol, LDL and HDL levels.

Blood Type Relationships

Type of Cholestrol & Desirable Values in IU

Total Cholesterol Below 200

HDL Cholesterol Above 45

LDL Cholestrol Below 130

LDL/HDL Ratio Below 3.0

What can I do to reduce my cholesterol?
There are several steps you can take to reduce your cholesterol levels. The first is to eat a low-fat, low-cholesterol diet. That means keeping your total fat consumption--saturated, polyunsaturated and monounsaturated--to fewer than 30 percent of your daily intake of calories. Remember to keep your cholesterol intake to fewer than 300 milligrams per day. Saturated fats contained in butter, whole milk, hydrogenated oils, chocolate shortening, etc. should comprise no more than one third of your total fat consumption. To reduce your total fat and cholesterol intake, limit your consumption of meats such as beef, pork, liver and tongue (always trim away excess fat). In addition, avoid cheese, fried foods, nuts and cream, and try to curb your intake of eggs to no more than four per week. Try to eat meatless meals several times a week, use skim milk and include fish in your diet. Eat a wide variety of vegetables, pasta, grains and fruit. Another good tip is to look at the package label of the foods you buy, and restrict your choices to foods containing 3 grams of fat or less per serving.
There is evidence that water-soluble fibers can aid in lowering cholesterol; these foods include the fiber in oat or corn bran, beans and legumes, pectin found in apples and other fruits, and guar that is used as a thickener. Although highly touted by the media and health food stores, the phospholipid Lecithin has not been confirmed as a reducer of blood cholesterol levels.
If you are overweight, trying to lose weight and including aerobic exercise in your routine can help raise those desirable HDL levels. Diet and exercise alone can decrease cholesterol levels by up to 15 percent.
It probably comes as no surprise to you that, if you smoke, you should quit to avoid a wide range of health problems, including lower HDL levels and increased risk of heart attack.

Foods That Lower Cholesterol Overview
A diet rich in fruits and vegetables is a great start toward lowering cholesterol.
The first line of defense against too much blood cholesterol is a diet that is rich in foods that lower cholesterol. A healthy diet should include plenty of vegetables, fruits, whole grains, and fiber, and be low in saturated fat, trans fat, and cholesterol. For the vast majority of Americans, eating healthy and losing excess weight are ideal ways to lower elevated cholesterol levels and keep those levels within a healthy range for life.
Even those foods or supplements that may have a beneficial effect on cholesterol need to be part of an overall heart-smart diet. Having oatmeal for breakfast and a glass of wine at dinner is fine, but if you add whole milk and butter to the oatmeal or have a Porterhouse steak with the wine, you're not doing your heart any favors.
So choose your foods wisely, and if a particular food or supplement appears to help, be sure to include it. But remember: Moderation is key. Don't overdo it with any supplement or food because, in some cases, that can cause just as many problems as high blood cholesterol.
Foods That Claim to Lower Cholesterol
Many foods and supplements claim to lower cholesterol. But do they really? Sometimes the answer is no, and sometimes the answer is that we don't know. In some instances, studies that support claims that a food lowers cholesterol are conducted by the very people who are selling the product, or the studies are poorly designed. In other instances, the studies conducted to test whether a food lowers cholesterol are just inconclusive.
The foods discussed on the following pages are ones that doctors don't recommend for a variety of reasons. If you are interested in taking a chance that these foods will work for you, talk with your doctor first. And keep a record every time you have your blood cholesterol tested to see if you experience any progress while taking these foods or supplements.
Flaxseed is a plant-based supplement that contains omega-3 fatty acids.

Foods That Claim to Lower Cholesterol
Flaxseed
Guggul
Lecithin
Policosanol
Red Yeast Rice Soy Garlic
Olive Oil
Fish oil
Plant Sterols
Whole grains
Dietary fibre
However studies are going on to rule out the authenticity of the claims for different food ingredients.

Medicating High Cholesterol
Sometimes positive changes in diet, lifestyle and exercise are not enough. In these cases, doctors may consider the use of medication that lowers cholesterol. The decision to have a patient begin medication is often based on high levels of LDL cholesterol and other risk factors for cardiovascular disease. For example, medication may be indicated if your LDL level is over 190 or is over 160 and you have several other risk factors for cardiovascular disease.
Drugs that reduce LDL blood levels can prevent or reduce the build-up of artery blocking plaques and can limit the possibility of the release of those plaques as dangerous blood clots. There are several types of drugs that can help reduce blood cholesterol levels. The most commonly prescribed are the statins, HMG-CoA reductase inhibitors, including:
· Lovastatin
· Simvastatin
· Atorvastatin, a new, highly potent drug

These drugs work within the liver to directly prevent the formation of cholesterol and can lower LDL cholesterol by as much as 40 percent. Research also shows that these drugs can reduce the risk of death from cardiovascular disease. Another major drug category is the resins, which bind bile acids, causing the liver to produce more of them and using up cholesterol in the process. By "tying" it up, these drugs make cholesterol less available in the blood. They include:
· Cholestyramine
· Colestipol
· The B vitamin Niacin, in high doses, can lower triglycerides and LDL levels and increase HDL levels. Niacin has been proven to reduce a person's risk of having a second heart attack.
Last are the drugs in the fibrates category, which lower triglycerides and can increase HDL levels. These include:
· Gemfibrozil
· Fenofibrate
The decision to take cholesterol- or lipid-lowering drugs is not taken lightly by your doctor. These drugs can be fairly expensive and are often required for many years or even the rest of your life. It is also important to note that some of these drugs can have dangerous side effects, such as damage to the liver.
Adopting a healthy lifestyle and visiting your doctor regularly can help curb your risks of problem cholesterol. Have your cholesterol levels checked by a physician, rather than risk incorrectly interpreting numbers in self test kits currently on the market. Remember, cholesterol is necessary for life but it can also be very harmful and requires monitoring. So, watch your cholesterol and keep in mind that, for every 1 percent drop in your cholesterol level, your risk of heart attack is lowered by 2 percent.

How Alcohol Lowers Cholesterol
For many people, a little alcohol, such as the ritual evening cocktail, is a sure cure for the day's troubles. These same individuals might not be surprised to learn that when consumed in moderation, alcohol may also offer some protection against heart disease. Research has shown that moderate consumption of alcohol can raise HDL cholesterol.
It may also decrease blood clotting and insulin resistance and is linked to lower levels of certain markers of inflammation, such as C-reactive protein, all of which may reduce the risk of heart disease. A modest alcohol intake may also reduce the risk of diabetes. This should be good news for those who imbibe in moderation -- that is, up to one drink per day for women and up to two drinks per day for men. (One drink consists of 1.5 ounces of hard liquor, 5 ounces of wine, or 12 ounces of beer.)
In the early 1990s, epidemiologists -- experts who specialize in the study of large populations to determine how various diseases occur and spread and how they can be controlled -- looked at data from countries around the globe and noticed that the coronary death rate for people in France was considerably lower than for people in the United States, despite French people's well-known love of high-fat foods.
In fact, the phenomenon called the French Paradox relates to the fact that the French have fewer heart attacks than Americans. This is a situation that could not be explained simply by comparing cholesterol levels in the two countries. Experts felt that this difference was due primarily to the French diet, which contains more red wine, fruits, and vegetables. Although red wine contains antioxidants and other compounds that may help prevent blood clots or the oxidation of LDL cholesterol, it has not been shown that only red wine is protective. In fact, most studies have linked moderate consumption of alcohol in general -- including wine, beer, and hard liquor -- to a reduced risk of heart disease.
But experts raise a red flag at the idea of encouraging the consumption of alcohol in order to raise HDL cholesterol or lower coronary rates. Not only are there better ways to raise HDL cholesterol (for example, regular physical exercise), but also not everyone can handle alcohol well.
Many doctors are concerned about safe levels of alcohol consumption for patients. They point out that consumption of as few as three to five alcoholic drinks per day is associated with adverse health effects, and heavy alcohol consumption may raise blood pressure, increase blood triglycerides, damage the liver, cause birth defects (when alcohol is consumed during pregnancy), and increase the risk of developing certain forms of cancer. Also, the majority of those who develop drinking problems drink relatively small amounts.


DISCLAIMER: This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Health Mirror, the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.

In case of any queries please feel free to contact Dr Anil K Dhull