It is often said that to prevent cardiovascular disease, one must reduce “bad” LDL cholesterol and increase “good” HDL cholesterol. But is it possible to have too much “good” cholesterol? Keep on reading to find out the answer!
Cholesterol is a fat necessary for the body to function. It enters into the composition of cell membranes and allows the synthesis of many hormones. It is not soluble in the blood and must, therefore, be transported by proteins, with which it forms complexes called lipoproteins. Cholesterol can be linked, in the blood, to two main types of “carriers”:
1) LDL (Low Density Lipoproteins)
LDL cholesterol is called “bad cholesterol”. LDLs bring cholesterol from the liver to the rest of the body. When the latter is in excess, it accumulates on the artery walls and forms a plaque, called atherosclerosis. Over time, a clot may eventually form and clog the bloodstream. If the obstruction occurs in an artery of the heart, this causes myocardial infarction (a heart attack). If it occurs in an artery of the brain, it causes a stroke. An excess of LDL cholesterol, therefore, increases the risk of cardiovascular disease.
2) HDL (High Density Lipoproteins)
HDL cholesterol is called “good cholesterol”. HDLs carry excess cholesterol from the body to the liver for removal. Thus, a high level of HDL cholesterol is associated with a lower cardiovascular risk.
In general, the normal values are to have an LDL-cholesterol level of less than 3.5 mmol/L and a HDL-cholesterol level greater than 1 mmol/L in men and 1.3 mmol/L in women. On the other hand, the target values depend on the age of the patient and other cardiovascular risk factors. They also vary slightly by country.