The following is a rule of thumb: about a quarter of the cholesterol that we need comes from our food; three quarters of it is formed in the liver and distributed throughout the body. However, this ratio changes if we consume more cholesterol. In this case, the liver produces less cholesterol and vice versa. This information brings into question the previous assumptions about the influence of food containing cholesterol has on our health. Since our body works would like to independently keep the cholesterol level at a constant level, it is not always the case that food with less cholesterol lowers the cholesterol level and food with more cholesterol increases it.
Cholesterol is transported in the blood by proteins, the lipoproteins, to the cells. These protein-cholesterol structures can be found in two different forms: as low density lipoprotein (LDL) and as high density lipoprotein (HDL). Any cholesterol that is not needed in the organism is returned to the liver by HDL for further processing. LDL cannot do this and deposits too much cholesterol, for example, on vascular walls. HDL is therefore seen as “good” cholesterol, while LDL is seen as “bad” cholesterol. While the LDL value should be kept as low as possible and should not exceed a certain level, a high HDL cholesterol value is beneficial.
A sufficient supply of unsaturated fatty acids is important for a healthy cholesterol level (HDL>LDL). Single and multiple unsaturated fatty acids can be found, for example, in fish, crustaceans and plant oils. Lean food rich in protein like shrimp and crustaceans, which contain both single and multiple unsaturated fatty acids, can lower the amount of “bad” LDL cholesterol in the blood. Both cholesterol values may increase with regular consumption, but the ratio of HDL to LDL improves in favour of the good cholesterol. Shrimp therefore has a positive effect on the cholesterol balance.
The discussion about cholesterol and food containing cholesterol should be just as nuanced as the discussion about fats. There are good and bad fatty acids and there is good and bad cholesterol.