An ingredient called phospholipids has started turning up in skincare (John Masters Organics vit C serum) and even haircare (Nioxin). When I found it in Trillium Organic's body scrub the other day, I was forced to admit that I didn't know much about it except that it is in cell membranes and the name (perhaps its the association with phosphorous) makes me think of fire flies. This didn't help me understand what its roles in skincare would be. It turns out they are multifarious, from keeping oils and water in potions mixed  together and, on our skins, as a complex protective barrier.

Phospholipids are comprised of two types of fatty acid. That puts them in the lipid family, a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K). The main biological functions of lipids include energy storage, as structural components of cell membranes, and as important signaling molecules.

The behavior of phospholids is wondrous and strange. They are described as having heads and tails. The 'head' of a phospholipid is hydrophilic (attracted to water), while the hydrophobic 'tails' repel water . This means that they attract water and hold on to it. This makes it a helpful moisturizer.

But that's not all. These heads and tails organize themselves into bio-layers (see the image above) that gives them a structure similar to that of skin. Because of this it is said that products that contain them have an affinity with the skin and high tolerance. And, what's more, phospholipids retain their structure when applied and because of this is sometimes called a “second skin”.

Amongst phospholipids, phosphatidylcholine unique because of its shape. It has a choline ‘head’ (choline is in cell-signaling molecules) and a chain of fatty acids making up the ‘tail’. Phosphatidylcholine is deemed to be the queen of phospholipids for cosmetic use because of its smaller molecular size. It contains choline (and this is the interesting part), therefore, it is a precursor to messenger molecules that go from cell to cell. And it can improve and protect cells and membrane damaged by free radicals.It is created by isolating distinct components from egg yolks and natural soy beans.

Phospholipids can be obtained from olive and hazelnut oils too. But only virgin oils. I found a study from 1990 that shows that phospolipids virtually disappear when oil is refined and the resulting oil had far less of a moisturizing effect than the phospholipid rich virgin oil.

As a workhorse, a phosopolipid is a useful emulsifier because it dissolves oil in water. Hence your potion doesn't look like an unshaken salad dressing. Also, a study has found that phospholipids are carriers or transdermal delivery systems that can help other ingredients penetrate.

Phospholipids also seems to be an antioxidant. Nicholas Perricone MD says it is so (and he should know being a doctor and all) and he uses the ingredient in, for example, his Cold Plasma cream. I also found studies that concluded that they have an antioxidant effect when combined with tocopherol (vitamin E).