Cholesterol is a fat-like substance that is found in everyone's body. Cholesterol is an important component of the outer lining (cell membrane) in every cell in your body. Also, cholesterol is necessary for your body to make its own vitamin D and certain important hormones. Unfortunately, excess cholesterol can deposit inside your arteries leading to hardening of the arteries ( "atherosclerosis") which in turn, increases your risk of having a heart attack or stroke.

That depends . . . if everyone in your family lived into their nineties and you have no other risk factors for developing atherosclerosis (see next section), a cholesterol level of 270 or higher may require no intervention. However, if you have already had a heart attack (which implies you already have atherosclerosis), a cholesterol level of 180 might be too high. Nevertheless, for most people, a cholesterol level more than 200 is considered too high. One explanation for this disparity in risk for a given total cholesterol level is due to the fact that not all cholesterol is created equal. There are actually two main types of cholesterol, "LDL-cholesterol" and "HDL-cholesterol". LDL cholesterol is the so called "bad" cholesterol because this type of cholesterol deposits inside your arteries and plugs them up. The HDL cholesterol is the so called "good" cholesterol because this cholesterol actually removes the cholesterol that is clogging your arteries. Therefore, it is more important for you to know what proportion of your total cholesterol is found as LDL or HDL cholesterol. In addition, blood cholesterol is only one factor (a risk factor) contributing to the development of atherosclerosis. Consider two people, both with a cholesterol of 240 mg/dl. If one person has no other risk factors for atherosclerosis, no treatment may be necessary while if the other person has several other risk factors for atherosclerosis, medications may be recommended to lower the cholesterol.

Besides having a high LDL cholesterol, other risk factors for developing atherosclerosis include:

• AGE: men over age 45 and women over age 55.
• FAMILY HISTORY: having a close relative with a heart attack prior to age 55 (in a man) or prior to age 65 (in a woman).
• TOBACCO: current cigarette smokers.
• HYPERTENSION: high blood pressure increases risk.
• DIABETES MELLITUS:
• LOW HDL CHOLESTEROL(less than 40 mg/dl): if you don't have enough of this "artery cleaning" cholesterol around, you have a better chance of developing atherosclerosis.

If you have never had any evidence of atherosclerosis (that is, you have never had a heart attack or stroke), your total cholesterol should be less than 200 mg/dl with the LDL cholesterol being less than 130 mg/dl while the HDL cholesterol should be greater than 40 mg/dl. If you are at very low risk for atherosclerosis (that is to say you have no risk factors or only one risk factor for developing atherosclerosis), then an LDL cholesterol of less than 160 mg/dl is acceptable. On the other hand, if you have had a heart attack or stroke in the past, you should try to get your bad cholesterol (LDL cholesterol) down to less than 100 mg/dl.

The two main ways of lowering the cholesterol level in your blood are through DIET and MEDICATIONS.

When most people are told to follow a cholesterol lowering diet, they think they must live by the motto "If it tastes good, spit it out!". Well, that statement doesn't need to be true as there are many tasty food choices in a cholesterol lowering diet. Many people are under the impression that they can lower the cholesterol level in their blood simply by eating foods low in cholesterol. This is simply not true. Most of the cholesterol in your blood comes from eating too much fat, not from eating too much cholesterol. Fortunately, foods low in fat are generally low in cholesterol so the fat content of a food and the cholesterol content go hand in hand most of the time. However, food manufacturers have exploited the public's misunderstanding of the role of dietary cholesterol on your blood cholesterol level. They will advertise a food as NO or LOW CHOLESTEROL, yet the food is loaded with fat. Such a food product will not help lower your blood cholesterol level. The FAT in your diet is the primary culprit that leads to an elevated blood cholesterol. Fat comes in three different types: saturated, monounsaturated and polyunsaturated. Of these different types of fat, saturated fat is thought to be the main contributor to high blood cholesterol levels. Most food labels list these different types of fat separately so start reading those labels! A cholesterol lowering diet should consist of:

• £30% of your total daily calories coming from fat, with at least 2/3 of the fat calories coming from monounsaturated and/or polyunsaturated fat,
• less than 300 mg cholesterol, and
• at least 20 grams of fiber (oat bran is a type of dietary fiber that lowers cholesterol).

There are a number of effective medications to lower cholesterol but cost and potential for serious side effects limit their use. Diet should always be tried first. If diet alone does not allow you to meet your goals, medications are sometimes prescribed. The main types of cholesterol lowering drugs include:

1. BILE ACID SEQUESTRANTS (Colestid^®, Questran^®): These drugs bind cholesterol in your intestine and are not absorbed into the body. They are gritty tasting and frequently lead to bloating and constipation. Since they are not absorbed, they are safe.

2. NIACIN. Niacin is a vitamin that can lower the blood cholesterol when taken at very high doses. Flushing is a common side effect of this medication but this side effect is lessened if you take an aspirin 30 minutes prior to taking the niacin. High doses of niacin can damage your liver. If you have diabetes, a peptic ulcer or gout, check with your doctor before starting niacin.

3. HMG Coenzyme reductase inhibitors (Baycol^®, Lescol^®, Lipitor^®, Mevacor^®, Pravachol^®, Zocor^®): These drugs decrease production of cholesterol in the liver. They are well tolerated and quite effective. Side effects include liver and muscle injury.

4. FIBRIC ACID DERIVATIVES (Lopid^®) This drug is especially helpful when the triglycerides (another fat in the blood) are also elevated. Nausea is a common side effect. Liver injury occurs rarely.

The health care team at Dubuque Internal Medicine has a lot of experience dealing with complex issues surrounding the diagnosis and treatment of high cholesterol. If you have any questions, please ask your doctor or nurse.