Heart disease is the leading cause of death in the United States. The National Heart, Lung and Blood Institute states that more than a million Americans have heart attacks each year, and half a million people die from heart disease. Because cholesterol is associated with heart disease, especially as people age, it is recommended that you get your cholesterol levels checked on a regular basis.
Function
Cholesterol is a waxy lipid used primarily to support the fluidity of cell membranes and as a precursor molecule to hormones. In order to be transported through the blood, cholesterol must be packaged by a lipoprotein, which is a molecule that combines a lipid and protein together. According to the American Heart Association, 75 percent of the blood cholesterol is manufactured by the liver and other cells. The rest comes from your diet.
Types
Five groups of lipoproteins exist but two main ones occupy the bloodstream. These are high-density lipoproteins, or HDL, and low- density lipoproteins, or LDL. Low-density lipoproteins are generally thought to be a "bad" form of cholesterol because they can clog arteries and narrow the walls of the blood. Therefore, cholesterol is a potential risk factor of heart disease. High-density lipoproteins, on the other hand, lead cholesterol away to be excreted.
HDL Range
According to the Mayo Clinic, cholesterol in the United States is measured in milligrams per deciliter---or a tenth of a liter. This is essentially a measure of the amount of lipoproteins that occupy a given volume of blood. An HDL level below 40 mg/dL is considered poor for men, and below 50 mg/dL is considered poor for women. A range of 50 to 59 mg/dL is considered better, and 60 mg/dL is best. The latter value is considered optimal as far as a normal healthy lifestyle goes and thus should be aimed for.
LDL Range
For LDL levels, a range below 70 mg/dL is ideal for people at a very high risk of heart disease, below 100 mg/dL is ideal for people at moderate risk for heart disease, 100 to 129 mg/dL is near ideal, 130 to 159 mg/dL is borderline high, 160 to 189 mg/dL is high and 190 mg/dL or above is very high.
Significance
The optimal target is to reduce LDL levels to below 130 mg/dL---and below 100 mg/dL if you are at risk for heart disease---by eating LDL-reducing foods, such as fiber and omega-3, at the same time that you constrict intake of trans fats and saturated fats. In addition, the presence of HDL can improve the condition of the cardiovascular system and potentially reduce the amount of total LDL. The optimal target of an HDL range above 60 mg/dL can be attained by eating a balanced diet and exercising on a regular basis.
