Cholesterol is a fatty substance that plays a critical role in the production of bile salts, steroid hormones and vitamin D. It is also a major component of the membranes that envelop and protect every cell in your body. The liver processes and packages cholesterol within molecules known as lipoproteins made out of proteins and fats. Low density lipoproteins, or LDL, contain more fats than proteins. High density lipoproteins, or HDL, contain more proteins than fats. Both types must fall within a specific range if you are to maintain proper health.
Measurements
Cholesterol is measured in three separate ways: by HDL levels, LDL levels and total cholesterol. The first two figures are more revealing than the third. LDL cholesterol can build up inside artery walls. This kind of blockage increases the risk of heart disease. HDL cholesterol prevents arteries from becoming clogged. Each one is measured by a unit known as mg/dl, or millimeters of cholesterol per deciliter of blood. A deciliter is 1/10 of a liter.
LDL and HDL Cholesterol
For LDL cholesterol, a healthy number is a reading of no more than 129 mg/dl. If you are at risk for heart disease, it should be no more than 99 mg/dl. If you are at a very high risk --- for example, if you have had a previous heart attack or stroke, and you meet certain risk factors --- then it should be no more than 69 mg/dl. The ideal number for HDL cholesterol, on the other hand, is at least 60 mg/dl. LDL is a maximum value, and HDL is a minimum value.
Total Cholesterol
Your total cholesterol should generally be no more than 200 mg/dl. There is no official minimum that constitutes a standard range. Everybody needs some cholesterol, and the amount of HDL should be maximized. A 1995 study published in the journal "Circulation" suggests that men, and to a lesser extent, women with total cholesterol levels below 160 mg/dl exhibited 10 to 20 percent additional mortality compared to individuals with cholesterol somewhere between 160 to 199 mg/dl. This latter number might be a comfortable range to aim for. But there is a second way to find a standard range. In general, the ratio of total cholesterol to HDL cholesterol should be, at its most ideal, somewhere between 3.5-to-1 and 5-to-1.
Treatments
Despite the similarities, cholesterol in the diet does not translate directly to cholesterol in the blood. Keeping cholesterol at a respectable level is more a matter of losing weight, exercising and eating a well-rounded diet. Limit your fat intake to between 20 and 35 percent of your total daily calories. Saturated fat should represent about 10 percent of your total calories. If you smoke, you should immediately quit.
