The No. 1 killer of American women isn't breast cancer. It's heart disease. And a major risk factor for heart disease is abnormal cholesterol levels.
But do you know what cholesterol is and what makes it so key to your heart health? 
Here are the answers to five important questions about cholesterol and your heart.
1. What is cholesterol?
Cholesterol is a fatty, waxlike substance. You get most of the cholesterol in your body from your liver. You also get a small amount from certain foods you eat, such as meat and dairy products. 
There are two major types of cholesterol in your blood:
<ul>
 <li>Low-density lipoprotein (LDL). This is sometimes called bad cholesterol because excess amounts of LDL tend to gather in the walls of your blood vessels.</li>
 <li>High-density lipoprotein (HDL). This type of cholesterol sweeps up excess LDL in the blood and takes it back to the liver, where it can be passed from the body. HDL is sometimes called good cholesterol.</li>
</ul>
Triglycerides are a third type of cholesterol. Having high levels of triglycerides is also unhealthy.
A common cholesterol problem is having too much LDL, too little HDL and excess amounts of triglycerides.
2. How does having too much LDL lead to heart disease?
LDL can collect inside the walls of blood vessels. Your blood vessels react by forming plaque, which can narrow and harden your arteries. This is called atherosclerosis. Plaque can break apart and form blood clots that block the flow of blood to the heart, causing a heart attack. 
3. Why do women have to worry about cholesterol?
Both men and women tend to have higher triglyceride and LDL levels as they get older. One of the reasons this happens to women is because of a loss of the hormone estrogen as they near menopause. Estrogen generally raises levels of HDL cholesterol, which makes it protective against heart disease. When estrogen levels drop around menopause, so do levels of HDL, raising the risk of atherosclerosis.
This is why women nearing menopause should have their cholesterol levels checked, reports the <a target="_blank" href="http://www.netreturns.biz/healthinfo/bouncelink.aspx?shortcut=aha">American Heart Association</a>. They can then talk about their risk factors for heart disease with their doctor and find out what lifestyle changes might help.
4. What are the symptoms of abnormal cholesterol levels?
There usually aren't any. Unless you get your cholesterol tested, chances are you won't know your levels are unhealthy until you have a heart attack or stroke. You should have your cholesterol levels checked with a blood test every five years beginning at age 45.
5. What can I do to change my cholesterol levels?
There's a lot you can do to manage your cholesterol levels. For example:
<ul>
 <li>Eat a heart-healthy diet. Limit foods high in saturated fats. Choose foods naturally high in fiber and unsaturated fats.</li>
 <li>Be physically active. Aim for 30 minutes of activity on five or more days of the week.</li>
 <li>Don&rsquo;t smoke. Smoking speeds up atherosclerosis and greatly increases your risk for heart disease.</li>
 <li>Know your family history. If unhealthy cholesterol levels run in your family, talk to your doctor. You may need to have your cholesterol tested earlier or more often.</li>
 <li>Work with your doctor. Your doctor may decide you need medications, such as statins, to help normalize your cholesterol levels.</li>
</ul>
Reviewed 11/10/2023

Women: What to know about cholesterol

Learn the answers to these 5 important questions about cholesterol.