Cholesterol is carried in particle form (as lipoproteins) through our bloodstream and is made available for use by various tissues. They are also eventually stored or excreted as waste.
When an excessive amount of lipoproteins circulate in the blood, there is a great risk of injury to the arteries - especially to the coronary arteries to the heart. When vessel linings are burdened by "plaque," heart-related diseases such as atherosclerosis set in.
Cholesterol needs to be transported as lipoproteins because they aren't soluble in blood. Lipoproteins are organic compounds which are composed of both protein and different fatty substances categorized as lipids - these include steroids (e.g., cholesterol) and fatty acids.
The two basic cholesterol types are high-density lipoproteins (HDL) and low-density lipoproteins (LDL). When you have your total cholesterol checked, both readings are usually given.
High-density lipoprotein (HDL)
It has been found that sufficient levels of HDL can significantly reduce the risk of heart disease. In fact, it has been thought by experts at the American Heart Association (AHA) to even help carry the bad cholesterol (see below) away from the arteries and transport them to the liver where they can be excreted from the body.
HDLs are cells that are smaller than LDLs and have a lower protein percentage. For women, the normal HDL cholesterol levels are 50-60 mg/dL and for men, the reading should ideally be 40-50 mg/dL.
The higher the levels of HDL in our bodies, the better it is for our hearts. A reading of less than 40 mg/dL increases our risk of having heart disease.
Low-density lipoprotein (LDL)
LDLs, on the other hand, are large molecules having a higher protein percentage than HDLs. They are the main system of transport of cholesterol and high levels of LDL mean an increased risk of heart disease, as well as stroke and heart attack, according to AHA. Together with other compounds, LDLs accumulate and form harmful plaque inside our arteries' walls, limiting our blood flow with possibly lethal blockages.
LDL levels of less than 100 mg/dL are considered optimal. When it reaches 130-159 mg/dL, it is considered "borderline high," while levels reaching 190 mg/dL and above are considered very high.
According to a report from the National Cholesterol Education Program (NCEP), more than 50 million adults in the U.S. alone could benefit from dietary therapy to help lower their cholesterol levels. So make sure to follow a proper diet to maintain a healthy life style.
