Jewish World Review August 31, 2004 / 14 Elul, 5764
Dr. Ed Blonz
Cholesterol not necessarily the culprit
DEAR DR. BLONZ: I have just returned from a physical and have again been counseled to avoid foods that contain cholesterol. My problem is that many of the foods I love to eat contain cholesterol. Aside from the fact that I have too much in my blood, how bad is cholesterol? What is the connection between the amount of cholesterol you eat and the amount in your blood? B.T., Saginaw, Mich.
DEAR B.T.: The connection between the cholesterol in our diets and the levels found in our blood is not as straightforward as it might seem. There are many factors involved, more than can be covered in one column. I will seek to focus this answer on aspects of the role of dietary cholesterol.
Let me start by saying that cholesterol, like fats and oils, has a unique ability to oxidize into troublesome compounds that can contribute to some of the major diseases humans face. Cholesterol is not the same as a fat or oil, but they all belong to the family of compounds known as lipids. This is why the proteins that carry this family around our bloodstreams are called "lipo" proteins. Some lipids are definitely worse than others, but all seem to have the potential to play a part in causing disease.
Cholesterol is a member of the class called "sterols," large complex lipid compounds that look like a small piece of chicken wire. It was originally found in gallstones, the painful masses that sometimes form from bile inside the gall bladder. Cholesterol serves many functions in the body, and is needed to help the brain function properly. It also keeps our skin watertight and provides the basic building block for sex hormones and other essential substances. The negative image of cholesterol comes from studies in which elevated blood cholesterol levels were identified as a predictor of conditions such as heart disease and stroke.
This was coupled with an examination of diseased arteries that found damage to the lining routinely included a cholesterol-laden buildup. It was unclear whether cholesterol was directly responsible, but the weight of circumstantial evidence was significant. There are scientists, however, who believe that cholesterol is only there as a part of the body's "repair crew" attempting to mend the injured blood vessels. (A real-world parallel might be erroneously blaming an ambulance for a traffic jam, when the accident is the actual cause and the ambulance is only there to help the accident's victims.) Others believe that only a particular form of cholesterol "oxidized cholesterol" is the villain. This is a type of cholesterol that sometimes occurs in processed foods. Regardless of the final scientific word, cholesterol remains convicted and sentenced to a life of dietary dishonor.
There is, however, an important distinction between cholesterol in our diets and the levels in our blood. In the average individual, the blood cholesterol-raising effect of dietary cholesterol appears to be of secondary importance. Only about half the amount of cholesterol we eat gets absorbed. Couple this with the fact that, even if there were absolutely no cholesterol in our diet, the body would continue to make plenty on its own.
Having a balanced diet and healthy lifestyle has always been the key to physical well-being. Cutting down on dietary cholesterol won't have a positive effect if your diet lacks the healthful nutrients found in greens, grains, fresh fruits and vegetables, nuts and seeds. It is the components in these foods that give the body the tools it needs to handle the dietary fats and cholesterol that are consumed. Eat and live well and the importance of dietary cholesterol shrinks dramatically.
You state that many of the foods you love to eat contain cholesterol. You also indicate that this is not the first time you have been counseled. If you want to keep the foods you cherish on your menu, it will serve you well to shift your lifestyle and dietary focus to include foods and activities that can help keep your body's healthful rhythms intact.
JWR contributor Ed Blonz, Ph.D., is a nutrition scientist and author of Power Nutrition and the "Your Personal Nutritionist" book series. Send questions to him by clicking here.
© 2004, NEA