Cholesterol travels through your body in carriers called lipoproteins. The outer layer of a lipoprotein contains protein and phospholipids and the inner layer is composed of cholesterol and other insoluble fats. Lipoproteins are categorized based on the ratio of cholesterol and protein that they contain. Each lipoprotein performs a different function in your body.
What is HDL?
HDL stands for high-density lipoprotein. High-density lipoproteins contain large amounts of protein and only small amounts of cholesterol and fat. HDL travels through your bloodstream, picking up excess cholesterol as it moves. The cholesterol collected by HDL is transported back to the liver where it is removed from the body. Because it contributes to cholesterol removal, HDL is considered protective against heart disease and is often referred to as good cholesterol.
HDL Levels
In order to reap the benefits of HDL, your blood must contain adequate amounts of the lipoprotein. The American Heart Association considers HDL levels of 60 mg/dL or above to be protective against heart disease. Adult men with HDL 40 mg/dL and below and adult women with HDL 50 mg/dL and below are considered to be at risk for heart disease.
What is LDL?
LDL stands for low-density lipoprotein. Low-density lipoproteins are the reverse of high-density lipoproteins. They contain high amounts of cholesterol and very small amounts of protein. LDL provides the body with the cholesterol that it needs in order to build cell membranes and synthesize bile, vitamin D and the hormones estrogen and testosterone. If you have too much LDL, however, cholesterol becomes deposited on the walls of your arteries, forming the plaque that contributes to atherosclerosis. Excess amounts of LDL cholesterol significantly reduce your risk of developing coronary artery disease or suffering from a heart attack or stroke. Because of this, LDL is often referred to as bad cholesterol.
LDL Levels
The goal for LDL is to get your numbers as low as possible. LDL levels below 70 mg/dL is considered ideal for people with a high risk of heart disease, according to MayoClinic.com. Levels below 100 mg/dL are ideal for those with some risk of heart disease and LDL levels between 100 and 129 mg/dL are defined as near ideal. When levels reach 130 to 159 mg/dL, they are considered borderline high. LDL levels from 160 to 189 mg/dL are high and levels 190 mg/dL and above are very high, states MayoClinic.com. High LDL levels significantly increase your risk of heart disease.
References
- "Nutrition and You"; Joan Salge Blake; 2008
- MayoClinic.com: High Cholesterol
- American Heart Association: LDL and HDL Cholesterol: What's Bad and What's Good?
- MayoClinic.com: Cholesterol levels: What numbers should you aim for?
