Dyslipidemia is an abnormally high or low concentration of lipids (cholesterol, triglycerides, phospholipids or free fatty acids) in the blood. There are several types, but cholesterol-related abnormalities are among the most common.
Cholesterol is a waxy substance (fat) naturally present in the body. It is used in the structure of cells, in the manufacture of certain hormones and vitamin D, and in the production of bile acids that help digest fats. Cholesterol comes from two sources: firstly, we make (mainly in the liver) the amount we need, but it is also present in some of the foods we eat. All foods containing animal fats contain some degree of cholesterol. The main sources of dietary cholesterol are cheese, egg yolks, beef, poultry and shrimps.
Cholesterol is therefore an essential substance for our bodies, but it is widely recognized that high cholesterol levels are one of the main risk factors for cardiovascular disease.
Cholesterol circulates in the blood in 2 forms, depending on its carrier: LDL (bad cholesterol) and HDL (good cholesterol).
« Bad » cholesterol can form deposits on artery walls (plaques). These deposits can narrow the arteries, reduce blood flow and can cause a heart attack or stroke. Conversely, high HDL levels reduce the risk of heart disease, hence the name « good »cholesterol. HDL («good» cholesterol) collects cholesterol and transports it to the liver, where it is eliminated.
Excessive LDL cholesterol and/or low HDL levels can be dangerous over the long term. Excess cholesterol deposits on the walls of arteries (such as the coronaries, the arteries of the heart), forming plaques that can grow over the years (atherosclerosis).
Plaques can slow down or even interrupt blood flow, causing angina pectoris or angina. If the flow is severely reduced, this may lead to myocardial infarction (destruction of heart tissue).