Cholesterol: What is it?

By: Laura Casselman, CPT

Cholesterol can be both good and bad, so it's important to know what cholesterol is and how it can affect your health for better or worse.

Cholesterol is a soft, fat-like, waxy substance found in your bloodstream as well as all cell membranes. It is vital to life and is necessary for the production of bile acids and steroid hormones. Cholesterol is important for the metabolism and transport of fatty acids and in the production of Vitamin D. However, too high a level of cholesterol in the blood is a major risk for coronary heart disease, which leads to heart attack. It's also a risk factor for stroke. Hypercholesterolemia is the term for high levels of blood cholesterol.

We get cholesterol in two different ways; our bodies produce it and we ingest it through animal products such as meats, poultry, fish, eggs, butter, cheese and whole milk. It may surprise you to learn that our bodies make all the cholesterol we need. About 85 percent of your blood cholesterol level is endogenous, which means your body produces it. The other 15 percent or so comes from an external source -- your diet.

The level of cholesterol already present in your blood can be increased by high consumption of cholesterol and saturated fat in your diet. Some foods that don't contain animal products may contain trans-fats, which cause your body to make more cholesterol, thus increasing blood cholesterol levels.

The good vs. the bad:
There are two different types of cholesterol -- good and bad. "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 is thought to provide some protection against artery blockage.

The average American woman eats between 220 and 260 milligrams of cholesterol a day. "As a rule, women have higher HDL cholesterol levels than men do. The female sex hormone estrogen tends to raise HDL cholesterol, which may help explain why premenopausal women are usually protected from developing heart disease."

The American Heart Association (AHA) suggests: "to reduce cholesterol in your blood, eat foods low in saturated fat and cholesterol, lose weight if you need to and exercise for a total of at least 30 minutes on most or all days of the week." Guidelines, for blood cholesterol levels, given by AHA are as follows:
Desirable - Less than 200 mg/dL
Borderline high risk - 200-239 mg/dL
High risk - 240 mg/dL and over