Cholesterol, a waxy fat-like substance, plays an important role in health, but cholesterol has earned a bad reputation because it also is linked to heart disease. Cholesterol strengthens every cell membrane and helps make vital compounds such as bile acids, sex hormones, adrenal hormones and vitamin D. However, it can build up in the arteries, block the flow of blood and lead to heart attack or stroke.
According to the Mayo Clinic, high cholesterol has no symptoms, so adults over age 20 need to have their cholesterol measured every 5 years. A fasting blood test called a lipoprotein profile measures total, LDL and HDL cholesterol and triglycerides.
Types of Cholesterol
Total cholesterol includes the combined measurements of your HDL, LDL and triglyceride levels as well as another component, VLDL, which carries triglyceride and is not usually reported on blood lipid profiles. Since fat does not dissolve in water or blood, cholesterol requires two transport vehicles, HDL and LDL, to help it move through the body. LDL moves cholesterol away from the liver, and HDL moves excess cholesterol back to the liver.
The National Cholesterol Education Program describes a total cholesterol level of less than 200 mg per deciliter as desirable, 200 mg to 239mg as borderline high, and 240 mg or above as a high level.
LDL Risk
People refer to cholesterol as "bad" when it travels within the LDL transporter to every cell in the body, putting more cholesterol into circulation. High levels of LDL cholesterol in the blood significantly increase the risk for heart disease and heart attack. The NCEP describes an LDL level of less than 100 mg per deciliter as optimal, 100 to 129 mg as near optimal, 130 to 159 mg as borderline high, 160 to 189 mg as high, and 190 mg or above as a very high level.
HDL Protection
People refer to cholesterol as "good" when it travels within the HDL transporter to come back to the liver for disposal or reprocessing. Good refers to the fact that HDL takes excess cholesterol out of circulation and protects against heart disease. An HDL level of less than 40 mg per deciliter is a major risk factor for heart disease, but an HDL level of 60 mg or more per deciliter protects the heart from disease.
Triglyceride Risk
Fat or triglyceride provides energy and insulation for the body. Triglyceride in the food eaten at dinner allows a person to stay active all evening. As Eleanor Whitney and Sharon Rolfes explain in the text "Understanding Nutrition," if a person does not eat for a period of time, stored triglycerides fuel his body until he eats again. High triglycerides can also increase the risk of heart disease.
Triglyceride categories indicate risk level and include a normal level of less than 150 mg per deciliter, borderline-high of 150 to 199 mg, high of 200 to 499 mg, or very high of 500 mg and above.
Treatment Options
According to the National Cholesterol Education Program, high cholesterol is largely preventable by diet, weight management, staying active and not smoking. Other factors include age, gender and heredity. The main goal of treatment is to lower the LDL level to reduce the risk of heart attack.
The National Heart, Lung and Blood Institute recommends the Therapeutic Lifestyle Changes, or TLC, diet. Consume 25 to 35 percent of calories from fat and less than 7 percent of calories from saturated fat. Consume less than 200 mg of dietary cholesterol per day and limit sodium to 2,400 mg per day. Limit calories to achieve and maintain a healthy weight. For some people, medication may be required to reduce cholesterol levels.
References
- Mayo Clinic: High Blood Cholesterol: Symptoms
- National Cholesterol Education Program: Cholesterol: What You Need to Know
- "Understanding Nutrition, Ninth Edition", Eleanor Noss Whitney and Sharon Rady Rolfes (2002).
- National Heart, Lung and Blood Institute: Therapeutic Lifestyle Changes Diet
- CDC: Cholesterol
