Lecithin: What is the common name for phosphatidylcholine?

November 10, 2025 •

2 min read

First isolated from egg yolk in 1846, phosphatidylcholine is a vital lipid found in all eukaryotic cell membranes. The common name for this essential compound is lecithin, though the terms describe distinct, albeit related, substances.

Quick Summary

The common name for phosphatidylcholine is lecithin. While the terms are often used interchangeably, lecithin is a broader mixture of phospholipids, with phosphatidylcholine being its most significant component.

Key Points

Lecithin is the common name: The term lecithin is the most common and widely recognized name for phosphatidylcholine.
Not perfectly synonymous: While often used interchangeably, lecithin is a mixture of phospholipids, whereas phosphatidylcholine is a specific compound.
Vital for cell structure: Phosphatidylcholine is the most abundant phospholipid in eukaryotic cell membranes and is critical for cell integrity and function.
Emulsifier properties: Due to its dual nature (water- and fat-loving), lecithin functions as an effective emulsifier in foods and the body.
Precursor to acetylcholine: Phosphatidylcholine is a source of choline, which the body uses to synthesize the important neurotransmitter acetylcholine.
Common dietary sources: Lecithin is found naturally in egg yolks and is commonly extracted commercially from soybeans and sunflower seeds.

Understanding the Common Name: Lecithin

When people refer to the substance known as lecithin, they are most often talking about phosphatidylcholine (PC), which is the primary component. This common name has a long history, dating back to 1846 when French chemist Theodore Nicolas Gobley first isolated the compound from egg yolk and named it after the Greek word for egg yolk, lekithos. While 'lecithin' is still widely used in the food and supplement industries, 'phosphatidylcholine' is the more scientifically accurate term for the specific chemical compound.

The Nuance: PC vs. Lecithin

Phosphatidylcholine is a specific glycerophospholipid molecule, while lecithin is a natural mixture of phospholipids and other substances like triglycerides. The makeup of lecithin varies based on its source, such as soybeans, sunflowers, or egg yolks. Pure PC is used in research and medicine, while commercial lecithin serves as a food emulsifier.

The Role of Phosphatidylcholine in the Body

Phosphatidylcholine is essential for numerous bodily functions.

Cell Membrane Structure

As the main phospholipid in cell membranes, PC is crucial for cell integrity and function. Its structure forms the lipid bilayer enclosing cells and organelles.

Neurological Function

PC provides choline, which is used to create the neurotransmitter acetylcholine, important for memory and muscle control. Maintaining adequate PC supports cognitive health.

Liver Health and Fat Metabolism

PC helps transport fats from the liver and emulsifies fats in bile for digestion, preventing fat buildup in the liver. It is also involved in lipoprotein transport.

Pulmonary Function

A specific PC, dipalmitoylphosphatidylcholine (DPPC), is a major part of pulmonary surfactant, which prevents lung collapse.

Sources of Phosphatidylcholine and Lecithin

Dietary PC comes from foods and supplements containing lecithin. Key sources include:

Egg yolks: A traditional source.
Soybeans: A common commercial source.
Sunflower seeds: A non-allergenic alternative.
Meat and whole grains: Also contribute dietary PC.

Comparison: Commercial Lecithin vs. Purified Phosphatidylcholine


Feature	Commercial Lecithin	Purified Phosphatidylcholine (PC)
Composition	A mixture of phospholipids (including PC), triglycerides, glycolipids, and sterols.	A standardized, single type of phospholipid molecule.
Purity	Varies depending on the source; not a pure compound.	Highly purified, often over 90% PC for specific applications.
Cost	Generally inexpensive, used widely in food production.	Significantly more expensive due to purification processes.
Uses	Emulsifier, viscosity modifier, release agent in processed foods.	Medical research, targeted dietary supplements, drug delivery systems.
Bioavailability	Good, but complex mixture means absorption varies.	Enhanced bioavailability and faster absorption in some cases.

The Commercial Application of Lecithin

Lecithin's emulsifying properties are widely used in the food industry to create stable emulsions between oils and water. Common uses include chocolate, margarine, baked goods, and ice cream.

Conclusion

The common name for phosphatidylcholine is lecithin, though they are distinct. PC is an essential phospholipid vital for cell structure, brain health, and fat metabolism. Lecithin is a broader mixture used commercially as an emulsifier and in supplements. Understanding this difference highlights PC's biological role and lecithin's practical uses. For more on PC's chemical structure, see the NCBI database. [https://pubchem.ncbi.nlm.nih.gov/compound/Phosphatidylcholine_1]

Frequently Asked Questions

No, they are not the same, though the terms are often used interchangeably. Phosphatidylcholine is a specific, purified chemical compound, whereas lecithin is a broader, naturally occurring mixture of phospholipids, in which phosphatidylcholine is the most significant component.

The term 'lecithin' was coined in 1846 by the chemist who first isolated the compound from egg yolk, its earliest known source. Because phosphatidylcholine is the primary active ingredient in most lecithin supplements and extracts, the common name stuck.

You can find phosphatidylcholine in foods that contain lecithin, such as eggs, soybeans, and sunflower seeds. Other sources include red meat and whole grains.

Phosphatidylcholine plays several key roles, including maintaining the structure of cell membranes, acting as a precursor for the neurotransmitter acetylcholine, and assisting in fat metabolism and transport in the liver.

Yes, their primary difference is their source, which affects their overall composition. Both are mixtures of phospholipids. Soy lecithin may contain soy allergens, making sunflower lecithin a preferable alternative for those with soy sensitivities.

Lecithin is an excellent emulsifier, meaning it can keep oil and water-based ingredients from separating. It is used to create smooth textures in products like chocolate and margarine.

Lecithin supplements provide a source of choline, which is beneficial for brain health and other body functions. However, it's important to note that most supplements contain a mixture of compounds, and consuming foods rich in PC and choline is a good first choice.