Cholesterol is a natural fatty substance that can have both beneficial and harmful effects on your health. Cholesterol is necessary for production of hormones (chemicals that control normal body function). It is also used to build and maintain nerve cells. At the same time, too much cholesterol can cause partial or total blockage of blood vessels; this may result in a stroke or heart attack. Cardiovascular disease (including heart attack and stroke) is the leading cause of death for women in the United States
Where does cholesterol come from? Most of the cholesterol is produced by the liver from fats, carbohydrates, and protein that you eat. Some cholesterol comes directly from the food that you eat (animal products only). Until you reach the menopause (the change), estrogen protects most women from the harmful effects of too much cholesterol. After the menopause, your risk of cardiovascular disease can rise. Hormone replacement therapy can help protect you from the effects of estrogen deficiency.  A study in Nature Medicine in 2007 demonstrated that estrogen replacement therapy begun near the time of menopause may help reduce atherosclerosis by blocking the attachment of cholesterol to the inside of blood vessels.  This helps explain the difference in age of onset of heart attacks in men and women (men start having heart attacks in their 40’s and women not until their 50’s or 60’s).
Cholesterol should be measured (with a simple blood test) every 5 years unless your physician advises it be checked more often. A lipid profile not only measures cholesterol but also measures:

• VLDL or very low density lipoprotein
• LDL or low density lipoprotein
• HDL or high density lipoprotein, and
• Triglycerides.

Fat is carried throughout your blood vessels to your fat tissue as VLDL. When some of the fat (but not the cholesterol) is deposited in your tissues, it becomes LDL. LDL is the so-called "bad cholesterol" because it can stick to your blood vessels and cause blockage. HDL, also called "good cholesterol," helps prevent cholesterol from building up on vessel walls. It does this by picking it up and carrying it back to the liver, where it is broken down and passed out of the body. The goal is to have a high HDL and a low LDL. Triglycerides are another type of fat that may be elevated in certain people. The levels found in the lipid profile are (you should discuss your levels with your physician to assess your personal risk):
Total cholesterol

• <200 good
• 200-239 borderline
• >239 not good

HDL cholesterol

• >59 good
• 35-59 normal
• <35 low (not good)

LDL cholesterol

• <100 optimal
• <130 good
• 130-159 borderline risk
• >159 high (not good)

Triglycerides

• <200 normal
• 200-400 borderline high
• 400-1,000 high
• >1,000 very high

The risk factors for developing atherosclerosis or cardiovascular disease include:

• family history of heart disease (especially before age 55 in men or before 65 in women)
• high LDL cholesterol (low HDL cholesterol)
• estrogen deficiency
• diabetes
• obesity
• inactive life style
• cigarette smoking

Recent medical study suggests that an elevated blood test, called high-sensitive C-reactive protein (hsCRP), increases the risk of cardiovascular disease, even when the LDL cholesterol is normal – the study also suggests that the patient will benefit from a class of drugs called statins that are traditionally used to treat elevated cholesterol.  The use of hsCRP for routine screening still needs to be validated as of Jan 2009.  Go to www.reynoldsriskscore.org for more information on risk assessment.
You cannot change your genetic predisposition for development of cardiovascular disease, but reducing the other risk factors can significantly affect your likelihood of cardiovascular disease.