A 2007 report from the Women's Health Study showed that high levels of cholesterol, even in healthy women, was a risk factor that increased a woman's chances of having a stroke. Other studies have shown a link between high levels of cholesterol and Alzheimer's disease. And the media has been warning us for years to cut down our intake of cholesterol because high cholesterol leads to hardening of the arteries. But what is cholesterol and why is it even it our bodies?

Cholesterol is a soft, waxy, fat-like substance that is made by the body. It is in all of your cells and can be found in all parts of the body including your skin, blood vessels, muscles, and so on. Since your body actively creates cholesterol, we can assume that having cholesterol in your body is not necessarily bad. In fact, you couldn't eliminate all the cholesterol in your body if you tried.

Cholesterol is important for the body. The cells use cholesterol as a building block in creating its protective membrane. Studies have indicated that "good" HDL cholesterol protects against heart disease and stroke even if "bad" LDL cholesterol levels are high. Good cholesterol helps to prevent dangerous breakaway blood clots - which can be caused by sitting in a cramped position for too long. Cholesterol also helps to manufacture vitamin D in the body from the sun. And there is much more good that cholesterol does for the body.

There is also a second source of cholesterol. Dietary cholesterol comes form the foods that we eat. It can be only be found in animal foods and eating it raises the bad cholesterol level in your own body. There have been many studies over the years that correlate a high intake of dietary cholesterol to coronary heart disease. In other words, the more high cholesterol foods we eat, the greater our chance of developing heart disease or a stroke.

High density lipoprotein (HDL), the good cholesterol, is a form of cholesterol that circulates in the bloodstream. One of its jobs is to remove excess cholesterol from the body's tissues and transport it to the liver where it will be excreted from the body. This process of "taking out the garbage" or cleansing the bloodstream is why HDL is a called good cholesterol and also why it's good for your body to have a relatively high HDL level. Some researchers say that an HDL of 60 milligrams per deciliter (mg/dl) or greater is good and will protect you against hardening of the arteries and lower your risk of getting heart disease.

Conversely, a low level of HDL, such as less then 40 mg/dl, has a negative effect. Many studies indicate that a low level of HDL combined with a high level of LDL seems to be a precursor of heart disease

You can control your cholesterol. The total amount of cholesterol in your body at any point in time is a function of how fast your HDL and liver can cleanse your system of it's existing cholesterol combined with the amount of dietary cholesterol that you've eaten during recent hours.

Controlling the amount of cholesterol that you allow into your body is a huge part of your lifestyle that you can modify to decrease your chances of heart disease or stroke. According to the American Heart Association, if you eat less then 300 milligrams of cholesterol a day, you can significantly reduce your cholesterol levels. By paying greater attention to the foods you eat, you can help to assure yourself of a long and healthy life.