People who eat a Mediterranean diet have more 'good' cholesterol in their blood than people who eat a Western diet. It has been known for some time that the Mediterranean diet results in lower LDL cholesterol levels (bad cholesterol). Now it has been discovered that this diet also leads to higher HDL cholesterol levels (good cholesterol). This was shown from doctoral research conducted by Marieke Bos of Wageningen University, which was financed by the Netherlands Heart Foundation. A low level of bad cholesterol and a high level of good cholesterol lowers the risk of cardiovascular disease.
Frequent consumption of olive oil, abundant fruit and vegetables, grain products, legumes, nuts, fish and a glass of red wine per day characterise the Mediterranean diet. The Wageningen research has shown that olive oil is partly responsible for the beneficial effect of the Mediterranean diet on blood cholesterol. In addition, the HDL level rises if you eat an entirely Mediterranean diet. In the Wageningen study, researchers replaced a large proportion of the saturated fat (such as butter and other ‘hard’ fats) in the Western diet with monounsaturated fat (such as olive oil). The resulted in a reduction of the harmful LDL cholesterol level in the blood. When the researchers replaced the Western diet entirely with the Mediterranean diet, this not only reduced the bad LDL cholesterol level; the good HDL blood cholesterol level also rose in the experimental subjects.
Cholesterol is an important building block for our body. However, excessive cholesterol is harmful. Excessive cholesterol can be laid down in our blood vessels. This causes them to become narrowed.
Protein cholesterol particles transport cholesterol. The LDL transports cholesterol to the various parts of the body. While underway, cholesterol can easily become attached to the walls of arteries and cause narrowing. LDL cholesterol is therefore referred to as ‘bad cholesterol’. The HDL cholesterol carries excess cholesterol to the liver, where it is transported to the intestines and is excreted. This is why HDL cholesterol is referred to as ‘good cholesterol’.
Marieke Bos defended her doctoral thesis on 27 May; her supervisors were Prof. Edith Feskens and Prof. Lisette de Groot of Wageningen University.