Unhealthy cholesterol levels (low HDL, high LDL, and high triglycerides) increase the risk for heart disease and heart attack. Some risk factors for cholesterol can be controlled (diet, exercise, weight) while others cannot (age, gender, and family history).
Age and Gender
From puberty on, men tend to have lower HDL (“good” cholesterol) levels than women. One reason is that the female sex hormone estrogen is associated with higher HDL levels. Because of this, premenopausal women generally have lower rates of heart disease than men. After menopause, as estrogen levels decline, women catch up in their rates of heart disease. Throughout the menopausal years, HDL levels decrease and LDL (“bad” cholesterol) and triglyceride levels increase. For men, LDL and triglyceride levels also rise as they age and the risks for heart disease increase as well. (There is some evidence that high triglyceride levels carry more risks for women than men.) Heart disease is the main cause of death for both men and women.
Children and Adolescents. Children who have abnormal cholesterol levels are at increased risk of developing heart disease later in life. However, it is difficult to distinguish “normal” cholesterol levels in children. Cholesterol levels tend to naturally rise sharply until puberty, decrease sharply, and then rise again.
Genetic Factors and Family History
Genetics play a major role in determining a person's blood cholesterol levels. (Children from families with a history of premature heart disease should be tested for cholesterol levels after they are 2 years old.) Genes may influence whether a person has low HDL levels, high LDL levels, high triglycerides, or high levels of other lipoproteins, such as lipoprotein(a).
Inherited cholesterol disorders include:
- Familial hypercholesterolemia is a genetic disorder that causes high cholesterol levels, particularly LDL, and premature heart disease. It occurs in as many as 1 in 500 people.
- Familial lipoprotein lipase deficiency is a very rare disorder that causes depletion of lipoprotein lipase. This is an enzyme that appears to be important in the removal of lipoproteins that are rich in triglycerides. People who are deficient in it have high levels of cholesterol and fat in their blood.
Review Date: 04/06/2010
Reviewed By: Harvey Simon, MD, Editor-in-Chief, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.