Lecithins are a group of chemical compounds and an important part of the cell membrane. Lecithins are vital for the human body.
What are lecithins?
Lecithins are chemical compounds that belong to the group of phosphatidylcholines. These are so-called phospholipids. These are made up of fatty acids, phosphoric acid, glycerine and choline.
The name lecithin comes from the Greek lekithos and means egg yolk. This name was chosen because lecithin was first isolated from egg yolks in 1846. It was only later found that the phospholipids can be found in all animal organisms and also in many plants.
Function, effect & tasks
Lecithins take on numerous functional tasks in the body. Their most important task is the formation of structure in the body. The living cells in the human body are surrounded by a cell membrane. This protects the cell organelles and maintains the internal milieu of the cell.
The cell membrane consists of a lipid bilayer. The lecithins are an important part of this lipid bilayer. Lecithins, together with other phospholipids, form what are known as hydrophilic windows in the impermeable membrane. Ions, water molecules and water-soluble substances enter the cell through these windows. The higher the lecithin content of the cell, the more actively the cell membrane can act.
In the nerves and brain, lecithin can be converted to acetylcholine in various chemical processes. Acetylcholine is one of the most important neurotransmitters in the human body. For example, it is responsible for transmitting nerve impulses to the heart. It is also the most important transmitter in the parasympathetic and sympathetic nervous system.
Lecithin stimulates enzymes that can neutralize and eliminate free radicals. Free radicals are molecules that are produced in many metabolic processes in the body. From a chemical point of view, they are incomplete. They lack an electron in their chemical structure. To make up for this deficiency, they try to steal this electron from other structures in the body. In doing so, they damage the cell membranes and also the entire cells of the body. Free radicals are believed to play a crucial role in causing cancer and other serious diseases.
Lecithins also play an important role in fat digestion. They act as an emulsifier of lipids in the blood. The body can only utilize the fats in emulsified form. Cholesterol is also emulsified by lecithins. This keeps the cholesterol soluble in the gallbladder. Without this emulsification, gallstones could form from the cholesterol. But lecithins can not only bind cholesterol, they can also activate enzymes that break down excess cholesterol. Thus, lecithins have a protective effect on blood vessels.
Education, occurrence, properties & optimal values
In the body, lecithins are largely found in the cell membranes. High concentrations of lecithin are found particularly in the liver, brain, lungs, heart and muscle tissue. Lecithin can also be found in the blood plasma.
Some of the lecithins, the phosphatidylethanolamines and the phosphatidylcholines, are produced in the Kennedy metabolic pathway. It is a biochemical process that takes place in nerve cells. Lecithins can, however, also be ingested through food. The main source of lecithins is soy. But rape, sunflower oil and of course egg yolk also contain lecithins. Lecithin levels in blood plasma are not determined. Therefore there are no reference values.
Diseases & Disorders
A lack of lecithins can lead to a wide variety of symptoms in the body. Lecithins play an important role in fat metabolism. In one study, men and women were given normal amounts of methionine and folic acid intravenously.
In the course of the study, the test subjects developed fatty liver and the first signs of liver damage became clear. Regular administration of lecithins could reverse these changes. Lecithins bind parts of so-called VLDL particles. These are responsible for the transport of fats from the liver to the tissues. The VLDL particles can no longer be produced without lecithins. The fat accumulates in the liver and damages the tissue there.
If there is a lack of lecithins, the rate of cell death within the liver appears to increase. Studies show that liver cells initiate programmed cell death, known as apoptosis, when they lack lecithins. In rats, a nutritional deficiency in lecithins resulted in an increased incidence of liver cancer. Sensitivity to cancer-causing chemicals also increased when there was a lack of lecithin.
Lecithins also seem to play an important role in Alzheimer's disease. Alzheimer's disease (Alzheimer's disease) is a disease of the nervous system. It occurs predominantly in people who are older than 65 years. A deterioration in cognitive performance is characteristic of the disease. The ability to remember is limited, the spatial orientation decreases, the experience of time is disturbed and the practical skills are limited. In addition, there are disorders of the language, a restriction of spatial-constructive abilities, a disruption of the inner drive and a fluctuating emotional state.
The exact causes of Alzheimer's disease are not yet clear. However, as the disease progresses, there is a lack of acetylcholine. The messenger substance is no longer produced in sufficient quantities. This leads to a reduced performance of the brain. In several studies, the administration of lecithins to Alzheimer's patients showed a slight improvement in memory performance. However, the lecithins cannot stop or even cure the disease. In view of the diverse effects of lecithin, however, care should be taken to ensure an adequate supply of phospholipids.
