Blood cholesterol is one of the major cardiovascular risk factors and premature death. Its concentrations should be low to prevent the risk of atherosclerosis (deposition of fat in the arteries). But, beware, there is cholesterol and cholesterol, the “good” cholesterol … and the “bad”. Learn how to read your results sheet.
The lipid balance should be done after 12 hours of fasting, which is why you will be asked to come to the analytical laboratory in the morning without having breakfast. The results should be interpreted according to your cardiovascular risk factors ( smoking , high blood pressure , diabetes , obesity , family history or personal heart disease …). The French Federation of Cardiology advocates better monitoring of its own cholesterol from 25 years.
Good cholesterol, bad cholesterol and total cholesterol: know how to differentiate
We distinguish :
- The HDL (High Density Lipoproteins), known as the “good cholesterol”. These proteins recover excess cholesterol and return it to the liver where it is transformed before being eliminated.
- The LDL (Low Density Lipoproteins), which transport cholesterol from the liver to all cells. But these LDL-cholesterols can accumulate and contribute to the formation of plaques that gradually clog the arteries.
- The total cholesterol corresponds to the HDL cholesterol (“good cholesterol”) and LDL (“bad cholesterol”).
|Cholesterol levels||Normal values|
|Total cholesterol||<2g / l|
|LDL – Cholesterol (bad cholesterol)||<1.6 g / l|
|HDL – Cholesterol (good cholesterol)||> 0.35 g / l|
|triglycerides||<1.5 g / l|
Total blood cholesterol
Cholesterol is a lipid (fat) whose origin is double. In part, it is made by the liver. For the rest, it is of food origin.
In France, it is assumed that the total cholesterol (CT) should be less than or equal to 2 g / l (5.1 mmol / l).
But, the lower it is, the better, as revealed by major international surveys.
Find out more on our cholesterol analysis sheet .
HDL-cholesterol or “good cholesterol”
It is a high-density lipoprotein (HDL), which has the function of transporting excess cholesterol in the blood to the liver and thus participates in the elimination of this fat by the body. This variable represents the “good” cholesterol , the one for which it is preferable to obtain strong values. The higher the blood level of HDL-cholesterol, the lower the risk of atherosclerosis.
HDL-cholesterol is generally measured by precipitation method.
Its concentration is usually considered to be at least 35 mg / dl or 0.9 mmol / l. The observed values are generally higher in women.
From HDL-cholesterol, the total cholesterol / HDL-cholesterol ratio can also be measured, the standard value of which is 4.0. Above this figure, it is estimated that the arterial risk is high.
Discover more information on our HDL-Cholesterol analysis sheet or “good cholesterol” .
LDL-cholesterol or “bad cholesterol”
It is a low-density lipoprotein (LDL), which transports cholesterol from food to tissues. It represents the “bad” cholesterol and it is good to have low levels of LDL-cholesterol. The probability of atherosclerosis is, in fact, all the stronger as the value of LDL-cholesterol is high.
The level of LDL-cholesterol is generally calculated from triglycerides (TG), another lipid variable, HDL-cholesterol and total cholesterol according to the Fridewald * formula.
The LDL-cholesterol level can also be measured by ultracentrifugation technique, but this dosage is not routinely performed.
The level of LDL-cholesterol to be reached depends on the cardiovascular risk of each patient. The level of risk is calculated for each patient according to known cardiovascular risk factors , based on the Systematic Coronary Risk Estimate (SCORE) which evaluates this risk at 10 years. (SCORE <1%), a moderate risk (1% ≤ SCORE <5%), a high risk (5% ≤ SCORE <10%) or a very high risk (SCORE ≥ 10%).
The objective of the LDL-Cholesterol level to be achieved must be:
- Less than or equal to 1.9 g / l (4.9 mmol / l) if the cardiovascular risk is low ;
- Less than or equal to 1.3 g / l (3.4 mmol / l) if the cardiovascular risk level is moderate ;
- Less than or equal to 1.0 g / l (2.6 mmol / l) if cardiovascular risk is high ;
- Less than or equal to 0.7 g / l (1.8 mmol / l) if the cardiovascular risk level is very high .
The level of risk will also make it possible to choose the best care. In the case of documented cardiovascular disease (history of infarction, avc, thrombosis …), cardiovascular risk is immediately considered very high and the management strategy is secondary prevention.
Other lipid balance variables
The lipid balance will also take into account other lipid parameters such as:
This is another category of lipids, which is associated with the risk of atherosclerosis, but less clearly than cholesterol. Their blood concentration is measured by enzymatic technique.
A triglyceride level of less than 1.5 g / l (1.7 mmol / L) is considered to be normal, and a rate greater than 2 g / l, regardless of the level of cholesterol in a person without a factor Of cardiovascular risk.
Between 2 and 4 g / l, the value of the triglycerides should be verified by a new lipid balance and it will be interpreted according to the values of the cholesterol and its subfractions.
Find out more about our triglyceride test sheet .