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Christine Lawhon



Lecithin, a lipid material composed of choline and inositol, is found in all living cells as a major component of cell membranes, which regulate the nutrients entering and exiting the cell. The term "lecithin" has two definitions depending on what group is using the term. Scientists define lecithin as synonymous with phosphatidylcholine, the name for one of the principle phospholipids. On the other hand, producers of lecithin for commercial use use the term lecithin to refer to a complex mix of phosphatides and other substances that contain phosphatidylcholine.



Lecithin can be naturally consumed through a diet including lecithin rich foods such as egg yolk, soybeans, grains, wheat germ, fish, legumes, yeast, and peanuts, to name a few. Lecithin supplements are sold to the public in capsule, powder or granular form. Lecithin is usually taken in a pill form or mixed into health shakes. Many companies advertise their supplies of lecithin as a dietary supplement on the web. Examples of supplement producers whom sell lecithin are The Herb Shop, All-Natural, Solgar, Health Revolution, Earth Legacy. Lecithin is also sold in many health food stores.

These commercial forms are highly filtered. The commercial, dietary supplement form of lecithin contains less that 35% of phosphatidylcholine. (Szuhaj, 325) The various substances included and the different amounts of phosphatidylcholine ("scientific" lecithin) depend on the method of its preparation and the source from which the lecithin was taken. (Hanin, 444) most of the commercially used lecithin is derived from soybeans. (Central Soy). Lecithin is also retailed as an emulsifying agent, allowing fats to be dispersed when mixed with water. This is a great aid in the production of foods such as margarine, mayonnaise, chocolate and baked goods because it keeps foods from sticking to themselves and other surfaces. Lecithin is even used for industrial purposes.



Lecithin is promoted as a quick fix for weight loss, as well as many other diseases and ailments. Lecithin supplement producers claim that lecithin has a beneficial role in:


None of the advertisements on the web have real scientific evidence for the effectiveness of lecithin in weight loss and fat metabolism, yet this is the supplement producers' main selling point for lecithin. The rational behind the fat metabolizing claim is due to lecithin's inherent role as an emulsifying agent. Producers claim that this characteristic of lecithin functions to break down the fat and disperses it in water and/or in our blood stream, allowing the fat to be flushed out of the body.



There is no scientific research that shows that lecithin aids in weight loss. In fact, lecithin supplements may actually cause weight gain due to the fact that it contains fatty acids and is thus highly caloric. There is just no validity to the rationale behind the weight loss claim. Lecithin makes sure that the fat and cholesterol that is travelling through the blood stream stays solvent in the water so that it will not attach to the artery walls. Even though lecithin does disperse fat in water and keeps fat from clogging the cardiovascular system, this does not mean that the subcutaneous fat that we associate with being overweight is just dissolved and flushed out by lecithin.


Humans get lecithin from cell production and from the nutrients in our diets. The estimated amount of lecithin in a human's diet is 50mg, which is sufficient for the body's proper functioning. Any healthy person whom consumes a well-balanced diet does not need to take lecithin supplements. But, what is considered a "well-balanced" diet? Not much is known about the relationship between the average person's dietary patterns, food processing and lecithin intake. Further studies of lecithin intake in the American diet would prove beneficial to resolve this question of the necessity of lecithin supplements. But "with our present available information there is no way of knowing whether long-term administration of lecithin at low doses has either a good, or detrimental effect". (Schenider, 181)


It is more reasonable to include extra lecithin in one's diet for health benefits such as decreased cholesterol levels or gallstone problems rather than for weight loss. But even research on lecithin's effects on these other ailments are inconclusive and irreplicable. Most of the scientific research conducted has been to test lecithin's effectiveness with neurological and liver diseases. Studies show conflicting results when examining lecithin's role in memory, probably due to the numerous uncontrollable and untestable variables involved with memory.


Many studies have been administered to test lecithin's effect on Alzheimer's disease. Lecithin produces the neurotransmitter acetylcholine which enables communication and signal-transmission between brain cells. Alzheimer's disease can be caused by a change in production of acetylcholine. Many speculate that an increase in lecithin will prompt brain cells to produce more acetylcholine, thus improving memory. Lecithin and choline have been tested to do this and neither has been proven to be affective. In most of these studies, a portion of subjects improved markedly, while others were not helped at all. (Zeisel, 334)


Lecithin "may lower cholesterol since lecithin is composed of polyunsaturated fatty acids, but studies have been inconclusive". (Thrive Online) "Although it is clear that lecithin administration can be beneficial for humans with tardive dyskinesia (a neurological disorder), and although there is reason to believe that normal memory can be influenced by the choline (found in lecithin) content of the diet, evidence available at this time does not justify the widespread us of lecithin for improved memory by the healthy general public" (Zeisel, 323). The only proven benefit and suggested use of lecithin or choline supplements is for those whom are taking niacin or nicotinic acid to treat high cholesterol. The niacin treatment can deplete choline, so an increased amount of lecithin or choline is necessary in the diet.



Most people do not feel any side effects when taking 10 to 30 grams per day of lecithin supplements. (Zeisel, 332) But in higher doses, lecithin supplements could cause gastrointestinal problems, diarrhea, weight gain, a rash and headache, nausea, vomiting, dizziness, and/or a "fishy" body odor.



Lecithin has received widespread attention recently for it's speculative treatment of many diseases and obesity. It has even been marketed as a product for those whom want to get rid of a little excess fat and improve muscle endurance. There is no proven evidence that suggests lecithin supplements have any effect in these areas, although studies continue to search for lecithin's role in these areas. Lecithin supplements at this time are not recommended for anyone, except for people taking niacin. Any diet or supplement that promises a quick fix to weight loss either has no scientific proof, and/or is probably a serious health risk. Lecithin supplements for weight loss fit into both of these categories. The more we search for answers, the more we come back to the same solution. The only safe, proven way to loose weight is through a healthy, low-fat diet with regular exercise. All the lecithin one needs for proper biological functioning is supplied in a healthy diet and by our own cell.



Barbeau, Andre M.D., John H. Growdon, M.D., Richard J. Wurtman, Nutrition and the Brain; Choline and Lecithin in Brain Disorders, (1979) Vol. 5, Raven Press, NY, 73, 76, 83, 113, 444.


Hanin, Israel, G. Brian Ansell, Lecithin : Technological, Biological, and Therapeutic Aspects, (1987), Plenum Press, NY, 180, 181.


Szuhaj, Bernard F., Gary R. List, Lecithins (1985), American Oil Chemists' Society, 323, 324, 326, 331-337.


Langer, Stephen, "Ekectrify your memory with brain-boosting nutrients", (June 1997) Better Nutrition, Atlanta, 36-47.


Web Sites: Thrive@health, Solgar, Etherington & Roberts, Health Revolution, Earth Legacy, Central Soya, The Herb Shop, All-natural


By Christine Lawhon


Psychology Department

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