FAMILY MEDICINE® COLUMN

By Martha A. Simpson, D.O., M.B.A.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

BROTHER’S CHOLESTEROL MAY REFLECT GOOD GENES, NOT LIFESTYLE

Question: My overweight brother, who is a 37-year-old smoker, said his cholesterol was 153. I'm pretty fit and don't smoke, but my cholesterol was 165. I'm also a vegetarian, and he is not. Why is my cholesterol so much higher than his?

Answer: First, let me tell you a little bit about this substance we call cholesterol. Many people don’t realize it, but cholesterol is actually a very important substance that’s vital for life. Found throughout the entire body, it’s used for digesting dietary fats, making hormones, building cell walls and other important processes. The cholesterol we worry about is the cholesterol that is in your bloodstream.

In the bloodstream, cholesterol is carried in “packets” called lipoproteins. You can think of these packets as freight train cars delivering cholesterol to various body tissues via the bloodstream, which in this analogy would be like a network of rail lines. When functioning normally, your body’s tissues, use, store or excrete the cholesterol that reaches them. However, too much circulating cholesterol can injure arteries, especially the coronary ones that supply the heart. This leads to accumulation of cholesterol-laden "plaque" in vessel linings, a condition called atherosclerosis.

The build-up of these plaques can impede the flow of blood to the heart. This, in turn, can starve the heart muscle of oxygen, causing the chest pain we call angina. If a blood clot completely obstructs one of these diseased arteries, it can bring on a heart attack.

Now, with that background information, I can answer your question directly. You and your brother have very desirable levels of total cholesterol, less than 200. The difference between 165 and 153 is really not significant.

Your concern seems to be that your brother’s lifestyle should make his cholesterol a lot higher than yours. On the surface that would seem so, but lifestyle is only one factor in determining your cholesterol levels.

You get cholesterol two ways -- from animal-based foods that you eat and from your body’s own internal cholesterol manufacturing system. Only 20 percent of total cholesterol comes from foods, the other 80 percent is manufactured.

In discussing cholesterol, it’s also important to distinguish between two types. There’s the “good cholesterol” or high density lipoprotein (HDL), and the “bad cholesterol” or low density cholesterol (LDL). It’s the LDL that clogs your arteries and the HDL that protects your arteries. So you and your brother should compare your HDL and LDL levels.

Another substance that is important in cardiac risk management is the triglyceride level. This is another fat substance that comes from foods and is manufactured by the body as well. Triglyceride levels are a bit more dependent on your food intake than cholesterol. You should have this tested as well so your doctor can determine your cardiac risk.

Finally, the similar cholesterol levels that you and your brother have may mean that you have both inherited good genes. This is a blessing for many people and is part of the reason that people that appear unhealthy often are not. However, in the long run, your brother would be well advised to quit smoking, eat a balanced diet, lose weight and get regular exercise. That would improve his cardiac risk.

Family Medicine® is a weekly column. To submit questions, write to Martha A. Simpson, D.O., M.B.A., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701, or via e-mail to readerquestions@familymedicinenews.org. Medical information in this column is provided as an educational service only. It does not replace the judgment of your personal physician, who should be relied on to diagnose and recommend treatment for any medical conditions. Past columns are available online at www.familymedicinenews.org.